Matter of sorroundings

As we look at our surroundings, we see a large

variety of things with different shapes, sizes

and textures. Everything in this universe is

made up of material which scientists have

named “matter”. The air we breathe, the food

we eat, stones, clouds, stars, plants and

animals, even a small drop of water or a

particle of sand– each thing is matter. We can

also see as we look around that all the things

mentioned above occupy space, that is,

volume* and have mass.

Since early times, human beings have

been trying to understand their surroundings.

Early Indian philosophers classified matter in

the form of five basic elements – the

“Panch Tatva”– air, earth, fire, sky and water.

According to them everything, living or nonliving,

was made up of these five basic

elements. Ancient Greek philosophers had

arrived at a similar classification of matter.

Modern day scientists have evolved two

types of classification of matter based on their

physical properties and chemical nature.

In this chapter we shall learn about

matter based on its physical properties.

Chemical aspects of matter will be taken up

in subsequent chapters.

1.1 Physical Nature of Matter

1.1.1 MATTER IS MADE UP OF PARTICLES

For a long time, two schools of thought

prevailed regarding the nature of matter. One

school believed matter to be continuous like

a block of wood, whereas, the other thought

that matter was made up of particles like

sand. Let us perform an activity to decide

about the nature of matter – is it continuous

or particulate?

Activity ______________ 1.1

• Take a 100 mL beaker.

• Fill half the beaker with water and

mark the level of water.

• Dissolve some salt/ sugar with the help

of a glass rod.

• Observe any change in water level.

• What do you think has happened to

the salt?

• Where does it disappear?

• Does the level of water change?

In order to answer these questions we

need to use the idea that matter is made up

of particles. What was there in the spoon, salt

or sugar, has now spread throughout water.

This is illustrated in Fig. 1.1.

1.1.2 HOW SMALL ARE THESE PARTICLES

OF MATTER?

Activity ______________ 1.2

• Take 2-3 crystals of potassium

permanganate and dissolve them in

100 mL of water.

Fig. 1.1: When we dissolve salt in water, the particles

of salt get into the spaces between particles

of water.

* The SI unit of volume is cubic metre (m3). The common unit of measuring volume is

litre (L) such that 1L = 1 dm3, 1L = 1000 mL, 1 mL = 1 cm3.

1

MATTER IN OUR SURROUNDINGS

Chapter

2 SCIENCE

• Take out approximately 10 mL of this

solution and put it into 90 mL of clear

water.

• Take out 10 mL of this solution and

put it into another 90 mL of clear water.

• Keep diluting the solution like this 5 to

8 times.

• Is the water still coloured ?

1.2.2 PARTICLES OF MATTER ARE

CONTINUOUSLY MOVING

Activity ______________ 1.3

• Put an unlit incense stick in a corner

of your class. How close do you have to

go near it so as to get its smell?

• Now light the incense stick. What

happens? Do you get the smell sitting

at a distance?

• Record your observations.

Activity ______________ 1.4

• Take two glasses/beakers filled with

water.

• Put a drop of blue or red ink slowly

and carefully along the sides of the first

beaker and honey in the same way in

the second beaker.

• Leave them undisturbed in your house

or in a corner in the class.

• Record your observations.

• What do you observe immediately after

adding the ink drop?

• What do you observe immediately after

adding a drop of honey?

• How many hours or days does it take

for the colour of ink to spread evenly

throughout the water?

Activity ______________ 1.5

• Drop a crystal of copper sulphate or

potassium permanganate into a glass

of hot water and another containing

cold water. Do not stir the solution.

Allow the crystals to settle at the

bottom.

• What do you observe just above the

solid crystal in the glass?

• What happens as time passes?

• What does this suggest about the

particles of solid and liquid?

• Does the rate of mixing change with

temperature? Why and how?

From the above three activities (1.3, 1.4 and

1.5), we can conclude the following:

Fig. 1.2: Estimating how small are the particles of

matter. With every dilution, though the colour

becomes light, it is still visible.

This experiment shows that just a few

crystals of potassium permanganate can

colour a large volume of water (about

1000 L). So we conclude that there must be

millions of tiny particles in just one crystal

of potassium permanganate, which keep on

dividing themselves into smaller and smaller

particles. Ultimately a stage is reached when

the particles cannot divide further into

smaller particles.

The same activity can be done using

2 mL of Dettol instead of potassium

permanganate. The smell can be detected

even on repeated dilution.

The particles of matter are very small –

they are small beyond our imagination!!!!

1.2 Characteristics of Particles of

Matter

1.2.1 PARTICLES OF MATTER HAVE SPACE

BETWEEN THEM

In activities 1.1 and 1.2 we saw that particles

of sugar, salt, Dettol, or potassium

permanganate got evenly distributed in water.

Similarly, when we make tea, coffee or

lemonade (nimbu paani ), particles of one type

of matter get into the spaces between particles

of the other. This shows that there is enough

space between particles of matter.

MATTER IN OUR SURROUNDINGS 3

• If we consider each student as a particle

of matter, then in which group the

particles held each other with the

maximum force?

Activity ______________ 1.7

• Take an iron nail, a piece of chalk and

a rubber band.

• Try breaking them by hammering,

cutting or stretching.

• In which of the above three substances

do you think the particles are held

together with greater force?

Activity ______________ 1.8

• Open a water tap, try breaking the

stream of water with your fingers.

• Were you able to cut the stream of

water?

• What could be the reason behind the

stream of water remaining together?

The above three activities (1.6, 1.7 and

1.8) suggest that particles of matter have force

acting between them. This force keeps the

particles together. The strength of this force

of attraction varies from one kind of matter

to another.

uestions

1. Which of the following are

matter?

Chair, air, love, smell, hate,

almonds, thought, cold, colddrink,

smell of perfume.

2. Give reasons for the following

observation:

The smell of hot sizzling food

reaches you several metres

away, but to get the smell from

cold food you have to go close.

3. A diver is able to cut through

water in a swimming pool. Which

property of matter does this

observation show?

4. What are the characteristics of

the particles of matter?

Particles of matter are continuously

moving, that is, they possess what we call

the kinetic energy. As the temperature rises,

particles move faster. So, we can say that with

increase in temperature the kinetic energy of

the particles also increases.

In the above three activities we observe

that particles of matter intermix on their own

with each other. They do so by getting into

the spaces between the particles. This

intermixing of particles of two different types

of matter on their own is called diffusion. We

also observe that on heating, diffusion

becomes faster. Why does this happen?

1.2.3 PARTICLES OF MATTER ATTRACT

EACH OTHER

Activity ______________ 1.6

• Play this game in the field— make four

groups and form human chains as

suggested:

• The first group should hold each other

from the back and lock arms like Bihu

dancers (Fig. 1.3).

Fig. 1.3

• The second group should hold hands

to form a human chain.

• The third group should form a chain

by touching each other with only their

finger tips.

• Now, the fourth group of students

should run around and try to break the

three human chains one by one into

as many small groups as possible.

• Which group was the easiest to break?

Why?

Q

4 SCIENCE

1.3 States of Matter

Observe different types of matter around you.

What are its different states? We can see that

matter around us exists in three different

states– solid, liquid and gas. These states of

matter arise due to the variation in the

characteristics of the particles of matter.

Now, let us study about the properties of

these three states of matter in detail.

1.3.1 THE SOLID STATE

Activity _____________ 1.9

• Collect the following articles— a pen, a

book, a needle and a piece of thread.

• Sketch the shape of the above articles

in your notebook by moving a pencil

around them.

• Do all these have a definite shape,

distinct boundaries and a fixed

volume?

• What happens if they are hammered,

pulled or dropped?

• Are these capable of diffusing into each

other?

• Try compressing them by applying

force. Are you able to compress them?

All the above are examples of solids. We

can observe that all these have a definite

shape, distinct boundaries and fixed volumes,

that is, have negligible compressibility. Solids

have a tendency to maintain their shape when

subjected to outside force. Solids may break

under force but it is difficult to change their

shape, so they are rigid.

Consider the following:

(a) What about a rubber band, can it

change its shape on stretching? Is it

a solid?

(b) What about sugar and salt? When

kept in different jars these take the

shape of the jar. Are they solid?

(c) What about a sponge? It is a solid

yet we are able to compress it. Why?

All the above are solids as:

• A rubber band changes shape under

force and regains the same shape when

the force is removed. If excessive force is

applied, it breaks.

• The shape of each individual sugar or

salt crystal remains fixed, whether we

take it in our hand, put it in a plate or in

a jar.

• A sponge has minute holes, in which

air is trapped, when we press it, the air

is expelled out and we are able to

compress it.

1.3.2 THE LIQUID STATE

Activity _____________1.10

• Collect the following:

(a) water, cooking oil, milk, juice, a

cold drink.

(b) containers of different shapes. Put

a 50 mL mark on these containers

using a measuring cylinder from

the laboratory.

• What will happen if these liquids are

spilt on the floor?

• Measure 50 mL of any one liquid and

transfer it into different containers one

by one. Does the volume remain the

same?

• Does the shape of the liquid remain the

same ?

• When you pour the liquid from one

container into another, does it flow

easily?

We observe that liquids have no fixed

shape but have a fixed volume. They take up

the shape of the container in which they are

kept. Liquids flow and change shape, so they

are not rigid but can be called fluid.

Refer to activities 1.4 and 1.5 where we

saw that solids and liquids can diffuse into

liquids. The gases from the atmosphere

diffuse and dissolve in water. These gases,

especially oxygen and carbon dioxide, are

essential for the survival of aquatic animals

and plants.

All living creatures need to breathe for

survival. The aquatic animals can breathe

under water due to the presence of dissolved

oxygen in water. Thus, we may conclude that

solids, liquids and gases can diffuse into

liquids. The rate of diffusion of liquids is

MATTER IN OUR SURROUNDINGS 5

higher than that of solids. This is due to the

fact that in the liquid state, particles move

freely and have greater space between each

other as compared to particles in the solid

state.

1.3.3 THE GASEOUS STATE

Have you ever observed a balloon seller filling

a large number of balloons from a single

cylinder of gas? Enquire from him how many

balloons is he able to fill from one cylinder.

Ask him which gas does he have in the cylinder.

Activity _____________1.11

• Take three 100 mL syringes and close

their nozzles by rubber corks, as

shown in Fig.1.4.

• Remove the pistons from all the

syringes.

• Leaving one syringe untouched, fill

water in the second and pieces of chalk

in the third.

• Insert the pistons back into the

syringes. You may apply some vaseline

on the pistons before inserting them

into the syringes for their smooth

movement.

• Now, try to compress the content by

pushing the piston in each syringe.

We have observed that gases are highly

compressible as compared to solids and

liquids. The liquefied petroleum gas (LPG)

cylinder that we get in our home for cooking

or the oxygen supplied to hospitals in

cylinders is compressed gas. Compressed

natural gas (CNG) is used as fuel these days

in vehicles. Due to its high compressibility,

large volumes of a gas can be compressed

into a small cylinder and transported easily.

We come to know of what is being cooked

in the kitchen without even entering there,

by the smell that reaches our nostrils. How

does this smell reach us? The particles of the

aroma of food mix with the particles of air

spread from the kitchen, reach us and even

farther away. The smell of hot cooked food

reaches us in seconds; compare this with the

rate of diffusion of solids and liquids. Due to

high speed of particles and large space

between them, gases show the property of

diffusing very fast into other gases.

In the gaseous state, the particles move

about randomly at high speed. Due to this

random movement, the particles hit each

other and also the walls of the container. The

pressure exerted by the gas is because of this

force exerted by gas particles per unit area

on the walls of the container.

Fig. 1.4

• What do you observe? In which case

was the piston easily pushed in?

• What do you infer from your

observations?

Fig.1.5: a, b and c show the magnified schematic

pictures of the three states of matter. The

motion of the particles can be seen and

compared in the three states of matter.

6 SCIENCE

1.4.1 EFFECT OF CHANGE OF TEMPERATURE

Activity _____________1.12

• Take about 150 g of ice in a beaker and

suspend a laboratory thermometer so

that its bulb is in contact with the ice,

as in Fig. 1.6.

uestions

1. The mass per unit volume of a

substance is called density.

(density = mass/volume).

Arrange the following in order of

increasing density – air, exhaust

from chimneys, honey, water,

chalk, cotton and iron.

2. (a) Tabulate the differences in

the characterisitcs of states

of matter.

(b) Comment upon the following:

rigidity, compressibility,

fluidity, filling a gas

container, shape, kinetic

energy and density.

3. Give reasons

(a) A gas fills completely the

vessel in which it is kept.

(b) A gas exerts pressure on the

walls of the container.

(c) A wooden table should be

called a solid.

(d) We can easily move our hand

in air but to do the same

through a solid block of wood

we need a karate expert.

4. Liquids generally have lower

density as compared to solids.

But you must have observed that

ice floats on water. Find out why.

1.4 Can Matter Change its State?

We all know from our observation that water

can exist in three states of matter–

• solid, as ice,

• liquid, as the familiar water, and

• gas, as water vapour.

What happens inside the matter during

this change of state? What happens to the

particles of matter during the change of

states? How does this change of state take

place? We need answers to these questions,

isn’t it?

Q

(a)

(b)

Fig. 1.6: (a) Conversion of ice to water, (b) conversion

of water to water vapour

MATTER IN OUR SURROUNDINGS 7

• Start heating the beaker on a low flame.

• Note the temperature when the ice

starts melting.

• Note the temperature when all the ice

has converted into water.

• Record your observations for this

conversion of solid to liquid state.

• Now, put a glass rod in the beaker and

heat while stirring till the water starts

boiling.

• Keep a careful eye on the thermometer

reading till most of the water has

vaporised.

• Record your observations for the

conversion of water in the liquid state

to the gaseous state.

On increasing the temperature of solids,

the kinetic energy of the particles increases.

Due to the increase in kinetic energy, the

particles start vibrating with greater speed.

The energy supplied by heat overcomes the

forces of attraction between the particles. The

particles leave their fixed positions and start

moving more freely. A stage is reached when

the solid melts and is converted to a liquid.

The temperature at which a solid melts to

become a liquid at the atmospheric pressure

is called its melting point.

The melting point of a solid is an

indication of the strength of the force of

attraction between its particles.

The melting point of ice is 273.16 K*. The

process of melting, that is, change of solid

state into liquid state is also known as fusion.

When a solid melts, its temperature

remains the same, so where does the heat

energy go?

You must have observed, during the

experiment of melting, that the temperature

of the system does not change after the

melting point is reached, till all the ice melts.

This happens even though we continue to

heat the beaker, that is, we continue to supply

heat. This heat gets used up in changing the

state by overcoming the forces of attraction

between the particles. As this heat energy is

absorbed by ice without showing any rise in

temperature, it is considered that it gets

hidden into the contents of the beaker and is

known as the latent heat. The word latent

means hidden. The amount of heat energy

that is required to change 1 kg of a solid into

liquid at atmospheric pressure at its melting

point is known as the latent heat of fusion.

So, particles in water at 00 C (273 K) have

more energy as compared to particles in ice

at the same temperature.

When we supply heat energy to water,

particles start moving even faster. At a certain

temperature, a point is reached when the

particles have enough energy to break free

from the forces of attraction of each other. At

this temperature the liquid starts changing

into gas. The temperature at which a liquid

starts boiling at the atmospheric pressure is

known as its boiling point. Boiling is a bulk

phenomenon. Particles from the bulk of the

liquid gain enough energy to change into the

vapour state.

For water this temperature is 373 K

(100 0C = 273 + 100 = 373 K).

Can you define the latent heat of

vaporisation? Do it in the same way as we

have defined the latent heat of fusion.

Particles in steam, that is, water vapour at

373 K (1000 C) have more energy than water

at the same temperature. This is because

particles in steam have absorbed extra energy

in the form of latent heat of vaporisation.

*Note: Kelvin is the SI unit of temperature, 00 C =273.16 K. For convenience, we take 00 C = 273 K

after rounding off the decimal. To change a temperature on the Kelvin scale to the Celsius scale

you have to subtract 273 from the given temperature, and to convert a temperature on the

Celsius scale to the Kelvin scale you have to add 273 to the given temperature.

So, we infer that the state of matter can

be changed into another state by changing

the temperature.

We have learnt that substances around

us change state from solid to liquid and from

liquid to gas on application of heat. But there

8 SCIENCE

closer? Do you think that increasing or

decreasing the pressure can change the state

of matter?

are some that change directly from solid state

to gaseous state and vice versa without

changing into the liquid state.

Activity _____________1.13

• Take some camphor or ammonium

chloride. Crush it and put it in a china

dish.

• Put an inverted funnel over the china

dish.

• Put a cotton plug on the stem of the

funnel, as shown in Fig. 1.7.

* atmosphere (atm) is a unit of measuring pressure exerted by a gas. The unit of pressure is Pascal (Pa):

1 atmosphere = 1.01 × 105 Pa. The pressure of air in atmosphere is called atmospheric pressure. The

atmospheric pressure at sea level is 1 atmosphere, and is taken as the normal atmospheric pressure.

Fig. 1.7: Sublimation of ammonium chloride

Fig. 1.8: By applying pressure, particles of matter

can be brought close together.

Applying pressure and reducing

temperature can liquefy gases.

Have you heard of solid carbon dioxide

(CO2)? It is stored under high pressure. Solid

CO2 gets converted directly to gaseous state

on decrease of pressure to 1 atmosphere*

without coming into liquid state. This is the

reason that solid carbon dioxide is also known

as dry ice.

Thus, we can say that pressure and

temperature determine the state of a

substance, whether it will be solid, liquid

or gas.

• Now, heat slowly and observe.

• What do you infer from the above

activity?

A change of state directly from solid to

gas without changing into liquid state (or vice

versa) is called sublimation.

1.4.2 EFFECT OF CHANGE OF PRESSURE

We have already learnt that the difference in

various states of matter is due to the

difference in the distances between the

constituent particles. What will happen when

we start putting pressure and compress a gas

enclosed in a cylinder? Will the particles come Fig. 1.9: Interconversion of the three states of matter

MATTER IN OUR SURROUNDINGS 9

dish and keep it inside a cupboard or

on a shelf in your class.

• Record the room temperature.

• Record the time or days taken for the

evaporation process in the above cases.

• Repeat the above three steps of activity

on a rainy day and record your

observations.

• What do you infer about the effect of

temperature, surface area and wind

velocity (speed) on evaporation?

You must have observed that the rate of

evaporation increases with–

• an increase of surface area:

We know that evaporation is a surface

phenomenon. If the surface area is

increased, the rate of evaporation

increases. For example, while putting

clothes for drying up we spread them out.

• an increase of temperature:

With the increase of temperature, more

number of particles get enough kinetic

energy to go into the vapour state.

• a decrease in humidity:

Humidity is the amount of water vapour

present in air. The air around us cannot

hold more than a definite amount of

water vapour at a given temperature. If

the amount of water in air is already high,

the rate of evaporation decreases.

• an increase in wind speed:

It is a common observation that clothes

dry faster on a windy day. With the

increase in wind speed, the particles of

water vapour move away with the wind,

decreasing the amount of water vapour

in the surrounding.

1.5.2 HOW DOES EVAPORATION CAUSE

COOLING?

In an open vessel, the liquid keeps on

evaporating. The particles of liquid absorb

energy from the surrounding to regain the

energy lost during evaporation. This

absorption of energy from the surroundings

make the surroundings cold.

uestions

1. Convert the following temperature

to celsius scale:

a. 300 K b. 573 K.

2. What is the physical state of

water at:

a. 250ºC b. 100ºC ?

3. For any substance, why does the

temperature remain constant

during the change of state?

4. Suggest a method to liquefy

atmospheric gases.

1.5 Evaporation

Do we always need to heat or change pressure

for changing the state of matter? Can you

quote some examples from everyday life where

change of state from liquid to vapour takes

place without the liquid reaching the boiling

point? Water, when left uncovered, slowly

changes into vapour. Wet clothes dry up.

What happens to water in the above two

examples?

We know that particles of matter are

always moving and are never at rest. At a

given temperature in any gas, liquid or solid,

there are particles with different amounts of

kinetic energy. In the case of liquids, a small

fraction of particles at the surface, having

higher kinetic energy, is able to break away

from the forces of attraction of other particles

and gets converted into vapour. This

phenomenon of change of a liquid into

vapours at any temperature below its boiling

point is called evaporation.

1.5.1 FACTORS AFFECTING EVAPORATION

Let us understand this with an activity.

Activity _____________1.14

• Take 5 mL of water in a test tube and

keep it near a window or under a fan.

• Take 5 mL of water in an open china

dish and keep it near a window or

under a fan.

• Take 5 mL of water in an open china

Q

10 SCIENCE

What happens when you pour some

acetone (nail polish remover) on your palm?

The particles gain energy from your palm or

surroundings and evaporate causing the

palm to feel cool.

After a hot sunny day, people sprinkle

water on the roof or open ground because

the large latent heat of vaporisation of water

helps to cool the hot surface.

Can you cite some more examples from

daily life where we can feel the effect of cooling

due to evaporation?

Why should we wear cotton clothes in

summer?

During summer, we perspire more

because of the mechanism of our body which

keeps us cool. We know that during

evaporation, the particles at the surface of

the liquid gain energy from the surroundings

or body surface and change into vapour. The

heat energy equal to the latent heat of

vaporisation is absorbed from the body

leaving the body cool. Cotton, being a good

absorber of water helps in absorbing the

sweat and exposing it to the atmosphere for

easy evaporation.

Why do we see water droplets on the outer

surface of a glass containing ice-cold

water?

Let us take some ice-cold water in a

tumbler. Soon we will see water droplets on

the outer surface of the tumbler. The water

vapour present in air, on coming in contact

with the cold glass of water, loses energy and

gets converted to liquid state, which we see

as water droplets.

uestions

1. Why does a desert cooler cool

better on a hot dry day?

2. How does the water kept in an

earthen pot (matka) become cool

during summer?

3. Why does our palm feel cold

when we put some acetone or

petrol or perfume on it?

4. Why are we able to sip hot tea or

milk faster from a saucer rather

than a cup?

5. What type of clothes should we

wear in summer?

More to know

Now scientists are talking of five states of matter: Solid, Liquid, Gas, Plasma and

Bose-Einstein Condensate.

Plasma: The state consists of super energetic and super excited particles. These

particles are in the form of ionised gases. The fluorescent tube and neon sign bulbs

consist of plasma. Inside a neon sign bulb there is neon gas and inside a fluorescent

tube there is helium gas or some other gas. The gas gets ionised, that is, gets charged

when electrical energy flows through it. This charging up creates a plasma glowing

inside the tube or bulb. The plasma glows with a special colour depending on the

nature of gas. The Sun and the stars glow because of the presence of plasma in

them. The plasma is created in stars because of very high temperature.

Bose-Einstein Condensate: In 1920, Indian physicist Satyendra Nath Bose had

done some calculations for a fifth state of matter. Building on his calculations, Albert

Einstein predicted a new state of matter – the Bose-

Einstein Condensate (BEC). In 2001, Eric A. Cornell,

Wolfgang Ketterle and Carl E. Wieman of USA received

the Nobel prize in physics for achieving “Bose-Einstein

condensation”. The BEC is formed by cooling a gas of

extremely low density, about one-hundred-thousandth

the density of normal air, to super low temperatures.

You can log on to www.chem4kids.com to get more

information on these fourth and fifth states of matter.

Q

S.N. Bose

(1894-1974)

Albert Einstein

(1879-1955)

MATTER IN OUR SURROUNDINGS 11

What

you have

learnt

• Matter is made up of small particles.

• The matter around us exists in three states— solid, liquid

and gas.

• The forces of attraction between the particles are maximum in

solids, intermediate in liquids and minimum in gases.

• The spaces in between the constituent particles and kinetic

energy of the particles are minimum in the case of solids,

intermediate in liquids and maximum in gases.

• The arrangement of particles is most ordered in the case of

solids, in the case of liquids layers of particles can slip and

slide over each other while for gases, there is no order, particles

just move about randomly.

• The states of matter are inter-convertible. The state of matter

can be changed by changing temperature or pressure.

• Sublimation is the change of gaseous state directly to solid

state without going through liquid state, and vice versa.

• Boiling is a bulk phenomenon. Particles from the bulk (whole)

of the liquid change into vapour state.

• Evaporation is a surface phenomenon. Particles from the

surface gain enough energy to overcome the forces of attraction

present in the liquid and change into the vapour state.

• The rate of evaporation depends upon the surface area exposed

to the atmosphere, the temperature, the humidity and the

wind speed.

• Evaporation causes cooling.

• Latent heat of vaporisation is the heat energy required to change

1 kg of a liquid to gas at atmospheric pressure at its boiling

point.

• Latent heat of fusion is the amount of heat energy required to

change 1 kg of solid into liquid at its melting point.

12 SCIENCE

Exercises

1. Convert the following temperatures to the Celsius scale.

(a) 300 K (b) 573 K.

2. Convert the following temperatures to the Kelvin scale.

(a) 25°C (b) 373°C.

3. Give reason for the following observations.

(a) Naphthalene balls disappear with time without leaving any

solid.

(b) We can get the smell of perfume sitting several metres away.

4. Arrange the following substances in increasing order of forces

of attraction between the particles— water, sugar, oxygen.

5. What is the physical state of water at—

(a) 25°C (b) 0°C (c) 100°C ?

6. Give two reasons to justify—

(a) water at room temperature is a liquid.

(b) an iron almirah is a solid at room temperature.

7. Why is ice at 273 K more effective in cooling than water at the

same temperature?

8. What produces more severe burns, boiling water or steam?

9. Name A,B,C,D,E and F in the following diagram showing change

in its state

Quantity Unit Symbol

Temperature kelvin K

Length metre m

Mass kilogram kg

Weight newton N

Volume cubic metre m3

Density kilogram per cubic metre kg m–3

Pressure pascal Pa

• Some measurable quantities and their units to remember:

MATTER IN OUR SURROUNDINGS 13

Group Activity

Prepare a model to demonstrate movement of particles in solids,

liquids and gases.

For making this model you will need

• A transparent jar

• A big rubber balloon or piece of stretchable rubber sheet

• A string

• Few chick-peas or black gram or dry green peas.

How to make?

• Put the seeds in the jar.

• Sew the string to the centre of the rubber sheet and put some

tape to keep it tied securely.

• Stretch and tie the rubber sheet on the mouth of the jar.

• Your model is ready. Now run your fingers up and down the

string by first tugging at it slowly and then rapidly.

Fig. 1.10: A model for happy converting of solid to liquid and liquid to gas.

INDIAN GEOGRAPHY

The Tropic of Cancer (23° 30'N) divides the
country into almost two equal parts. To the
southeast and southwest of the mainland, lie
the Andaman and Nicobar islands and the
Lakshadweep islands in Bay of Bengal and
Arabian Sea respectively. Find out the extent
of these groups of islands from your atlas.
SIZE
The land mass of India has an area of 3.28
million square km. India’s total area accounts
for about 2.4 per cent of the total geographical
India is one of the ancient civilisations in the
world. It has achieved multi-faceted socioeconomic
progress during the last five
decades. It has moved forward displaying
remarkable progress in the field of
agriculture, industry, technology and overall
economic development. India has also
contributed significantly to the making of
world history.
LOCATION
India is a vast country. Lying entirely in the
Northern hemisphere (Figure 1.1) the main
land extends between latitudes 8°4'N and
37°6'N and longitudes 68°7'E and 97°25'E.
INDIA – SIZE AND LOCATION
Figure 1.1 : India in the World
• The southernmost point of
the Indian Union– ‘Indira Point’ got submerged under
the sea water in 2004 during the Tsunami.
180°W 150° 120° 90° 60° 30°W 0° 30°E 60° 90° 120° 150° 180°E
INDIAN
OCEAN
Antartica
75°N
60°
30°
15°N
0°
15°S
45°
60°
75°S
PACIFIC
OCEAN
ATLANTIC
OCEAN
PACIFIC
OCEAN
Africa
Asia 45° Europe
North
America
South
America
Australia
30°
1
2 CONTEMPORARY INDIA
area of the world. From the Figure 1.2 it is
clear that India is the seventh largest
country of the world. India has a land
boundary of about 15,200 km and the total
length of the coast line of the mainland
including Andaman and Nicobar and
Lakshadweep is 7,516.6 km.
India is bounded by the young fold
mountains in the northwest, north and
north east. South of about 22° north
latitude, it begins to taper, and extends
towards the Indian Ocean, dividing it into
two seas, the Arabian Sea on the west and
the Bay of Bengal on its east.
Look at Figure 1.3 and note that the
latitudinal and longitudinal extent of the
mainland is about 30°. Despite this fact the
east-west extent appears to be smaller than
the north-south extent.
From Gujarat to Arunachal Pradesh
there is a time lag of two hours. Hence, time
along the Standard Meridian of India
(82°30'E) passing through Mirzapur (in
Uttar Pradesh) is taken as the standard time
for the whole country. The latitudinal extent
influences the duration of the day and night,
as one moves from south to north.
• Why 82°30'E has been selected as the Standard
Meridian of India?
• Why is the difference between the durations
of day and night hardly felt at Kanniyakumari
but not so in Kashmir?
INDIA AND THE WORLD
The Indian landmass has a central location
between the East and the West Asia. India is a
southward extension of the Asian Continent.
The trans Indian Ocean routes which connect
the countries of Europe in the West and the
countries of East Asia provide a strategic central
location to India. Note that the Deccan Peninsula
protrudes into the Indian Ocean, thus helping
India to establish close contact with West Asia,
Africa and Europe from the western coast and
with Southeast and East Asia from the eastern
coast. No other country has a long coastline on
the Indian Ocean as India has and indeed, it is
India’s eminent position in the Indian Ocean
which justifies the naming of an Ocean after it.
Figure 1.2 : Seven Largest Countries of the World
Source : Based on World Population Data Sheet, 2005, Population Reference Bureau, Washington, DC
Since the opening of the
Suez Canal in 1869, India’s distance from Europe
has been reduced by 7,000 km.
INDIA – SIZE AND LOCATION 3
Figure 1.3 : India : Extent and Standard Meridian
4 CONTEMPORARY INDIA
Figure 1.4 : India on International Highway of Trade and Commerce
• The number of Union Territories
along the western and eastern coasts.
• Area-wise which is the smallest and which is
the largest state?
• The states which do not have an international
border or lie on the coast
• Classify the states into four groups each
having common frontiers with
(i) Pakistan, (ii) China, (iii) Myanmar, and
(iv) Bangladesh.
India shares its land boundaries with
Pakistan and Afghanistan in the northwest,
China (Tibet), Nepal and Bhutan in the north
and Myanmar and Bangladesh in the east.
Our southern neighbours across the sea
consist of the two island countries, namely
India’s contacts with the World have
continued through the ages but her relationships
through the land routes are much older than
her maritime contacts. The various passes across
the mountains in the north have provided
passages to the ancient travellers, while the
oceans restricted such interaction for a long time.
These routes have contributed in the
exchange of ideas and commodities since
ancient times. The ideas of the Upanishads
and the Ramayana, the stories of Panchtantra,
the Indian numerals and the decimal system
thus could reach many parts of the world. The
spices, muslin and other merchandise were
taken from India to different countries. On the
other hand, the influence of Greek sculpture,
and the architectural styles of dome and
minarets from West Asia can be seen in
different parts of our country.
INDIA’S NEIGHBOURS
India occupies an important strategic position
in South Asia. India has 28 states and 7 Union
Territories (Figure 1.5).
Before 1947, there were two
types of states in India – the provinces and the
Princely states. Provinces were ruled directly by
British officials who were appointed by the
Viceroy. Princely states were ruled by local,
hereditary rulers, who acknowledged sovereignity
in return for local autonomy.
INDIA – SIZE AND LOCATION 5
Figure 1.5 : India and Adjacent Countries
Sri Lanka and Maldives. Sri Lanka is
separated from India by a narrow channel
of sea formed by the Palk Strait and the Gulf
of Mannar while Maldives Islands are situated
to the south of the Lakshadweep Islands.
India has had strong geographical and
historical links with her neighbours. Look
at the physical map of Asia in your atlas,
and note how India stands apart from the
rest of Asia.
6 CONTEMPORARY INDIA
1. Choose the right answer from the four alternatives given below.
(i) The Tropic of Cancer does not pass through
(a) Rajasthan (c) Chhattisgarh
(b) Orissa (d) Tripura
(ii) The easternmost longitude of India is
(a) 97° 25' E (c) 77° 6' E
(b) 68° 7' E (d) 82° 32' E
(iii) Uttaranchal, Uttar Pradesh, Bihar, West Bengal and Sikkim have common
frontiers with
(a) China (c) Nepal
(b) Bhutan (d) Myanmar
(iv) If you intend to visit Kavarati during your summer vacations, which one of
the following Union Territories of India you will be going to
(a) Pondicherry (c) Andaman and Nicobar
(b) Lakshadweep (d) Diu and Daman
(v) My friend hails from a country which does not share land boundary with
India. Identify the country.
(a) Bhutan (c) Bangladesh
(b) Tajikistan (d) Nepal
2 Answer the following questions briefly.
(i) Name the group of islands lying in the Arabian sea.
(ii) Name the countries which are larger than India.
(iii) Which island group of India lies to its south-east?
(iv) Which island countries are our southern neighbours?
3 The sun rises two hours earlier in Arunachal Pradesh as compared to Gujarat
in the west but the watches show the same time. How does this happen?
4 The central location of India at the head of the Indian Ocean is considered of
great significance. Why?
MAP SKILLS
1. Identify the following with the help of map reading.
(i) The Island groups of India lying in the Arabian Sea and the Bay of Bengal.
(ii) The countries constituting Indian Subcontinent.
(iii) The states through which the Tropic of Cancer passes.
(iv) The northernmost latitude in degrees.
(v) The southernmost latitude of the Indian mainland in degrees.
(vi) The eastern and the western most longitude in degrees.
(vii) The place situated on the three seas.
(viii) The strait separating Sri Lanka from India.
(ix) The Union Territories of India.
PROJECT/ACTIVITY
(i) Find out the longitudinal and latitudinal extent of your state.
(ii) Collect information about the ‘Silk Route’. Also find out the new
developments, which are improving communication routes in the regions of
high altitude.
EXERCISE



You have already learnt earlier that India
is a vast country with varied landforms.
What kind of terrain do you live in? If
you live in the plains you are familiar with the
vast stretches of plain land. In contrast, if you
live in hilly region, the rugged terrain with
mountains and valleys are common features.
In fact, our country has practically all major
physical features of the earth i.e. mountains,
plains, deserts, plateaus and islands. You
must be wondering how these physical
features have been formed. We will learn more
about major physical features of India and how
they have been formed.
We find different types of rocks; some are
very hard like marble which has been used for
making the Taj Mahal, and some are very soft
like soap stone which is used in making talcum
powder. The colour of soil varies from one place
to the other because soil is formed out of
different types of rocks. Have you ever thought
about the causes of these variations? Most of
these variations are caused due to differences
in rock formations.
India is a large landmass formed during
different geological periods which has influenced
her relief. Besides geological formations, a
number of processes such as weathering,
erosion and deposition have created and
modified the relief to its present form.
Earth scientists have attempted to explain
the formation of physical features with the help
of some theories based on certain evidences.
One such plausible theory is the “Theory of Plate
Tectonics”. According to this theory, the crust
(upper part) of the earth has been formed out of
seven major and some minor plates. (Figure 2.2)
PHYSICAL FEATURES OF INDIA
The movement of the plates results in the
building up of stresses within the plates and the
continental rocks above, leading to folding,
faulting and volcanic activity. Broadly, these
plate movements are classified into three
types(Figure 2.1). While some plates come towards
each other and form convergent boundary. Some
plates move away from each other and form
divergent boundary. In the event of two plates
coming together they may either collide and
crumble, or one may slide under the other. At
times, they may also move horizontally past
PLATE PLATE
Divergent Boundary
Mantle
Convergent Boundary
PLATE
PLATEPLATE
PLATE
PLATE
Mantle
Transform Boundary
Mantle
Mantle
Figure 2.1 : Plate Boundaries
2
8 CONTEMPORARY INDIA
each other and form transform boundary. The
movement of these plates have changed the
position and size of the continents over millions
of years. Such movements have also influenced
the evolution of the present landform features
relief of India.
Gondwanaland: It is the southern part of the ancient
super continent Pangea with Angara Land in the
northern part.
The Himalayan uplift out of the Tethys sea
and subsidence of the northern flank of the
peninsular plateau resulted in the formation
of a large basin. In due course of time this
depression, gradually got filled with deposition
of sediments by the rivers flowing from the
mountains in the north and the peninsular
plateau in the south. A flat land of extensive
alluvial deposits led to the formation of the
northern plains of India.
The land of India displays great physical
variation. Geologically, the Peninsular Plateau
constitutes one of the ancient landmasses on
the earth’s surface. It was supposed to be one
of the most stable land blocks. The Himalayas
and the Northern Plains are the most recent
landforms. From the view point of geology,
Himalayan mountains form an unstable zone.
The whole mountain system of Himalaya
represents a very youthful topography with
high peaks, deep valleys and fast flowing rivers.
The northern plains are formed of alluvial
Most volcanoes and
earthquakes in the world are located at plate
margins, but some do occur within the plates.
Figure 2.2 : World : Plate Margins
The oldest landmass, (the Peninsula part), was
a part of the Gondwana land. The Gondwanaland
included India, Australia, South Africa and South
America as one single land mass. The convectional
currents split the crust into a number of pieces,
thus leading to the drifting of the Indo-Australian
plate after being separated from the Gondwana
land, towards north. The northward drift resulted
in the collision of the plate with the much larger
Eurasian Plate. Due to this collision, the
sedimentary rocks which were accumulated in
the geosyncline known as the Tethys were folded
to form the mountain system of western Asia and
Himalaya.
PHYSICAL FEATURES OF INDIA 9
deposits. The peninsular plateau is composed
of igneous and metamorphic rocks with gently
rising hills and wide valleys.
MAJOR PHYSIOGRAPHIC DIVISIONS
The physical features of India can be grouped
under the following physiographic divisions
(Figure 2.4):
(i) The Himalayan Mountains
(ii) The Northern Plains
(iii) The Peninsular Plateau
(iv) The Indian Desert
(v) The Coastal Plains
(vi) The Islands
The Himalayan Mountains
The Himalayas, geologically young and
structurally fold mountains stretch over the
Figure 2.3 : Himalayas
northern borders of India. These mountain
ranges run in a west-east direction from the
Indus to the Brahmaputra. The Himalayas
represent the loftiest and one of the most
rugged mountain barriers of the world. They
form an arc, which covers a distance of about
2,400 Km. Their width varies from 400 Km
in Kashmir to 150 Km in Arunachal Pradesh.
The altitudinal variations are greater in the
eastern half than those in the western half.
The Himalaya consists of three parallel
ranges in its longitudinal extent. A number
of valleys lie between these ranges. The
northern most range is known as the Great
or Inner Himalayas or the ‘Himadri’. It is the
most continuous range consisting of the
loftiest peaks with an average height of 6,000
metres. It contains all the prominent
Himalayan peaks.
10 CONTEMPORARY INDIA
Figure 2.4 : Relief
PHYSICAL FEATURES OF INDIA 11
Some Highest Peaks of the Himalayas
Peak Country Height
in metres
Mt. Everest Nepal 8848
Kanchenjunga India 8598
Makalu Nepal 8481
Dhaulagiri Nepal 8172
Nanga Parbat India 8126
Annapurna Nepal 8078
Nanda Devi India 7817
Kamet India 7756
Namcha Barwa India 7756
Gurla Mandhata Nepal 7728
The folds of Great Himalayas are
asymmetrical in nature. The core of this part
of Himalayas is composed of granite. It is
perennially snow bound, and a number of
glaciers descend from this range.
alluvium. The longitudinal valley lying
between lesser Himalaya and the Shiwaliks are
known as Duns. Dehra Dun, Kotli Dun and
Patli Dun are some of the well-known Duns.
Besides the longitudinal divisions, the
Himalayas have been divided on the basis of
regions from west to east. These divisions
have been demarcated by river valleys. For
example, the part of Himalayas lying between
Indus and Satluj has been traditionally
known as Punjab Himalaya but it is also
known regionally as Kashmir and Himachal
Himalaya from west to east respectively. The
part of the Himalayas lying between Satluj
and Kali rivers is known as Kumaon
Himalayas. The Kali and Tista rivers
demarcate the Nepal Himalayas and the part
lying between Tista and Dihang rivers is
known as Assam Himalayas. There are
regional names also in these broad
categories. Find out some regional names of
the Himalayas
The Brahmaputra marks the eastern most
boundary of the Himalayas. Beyond the Dihang
gorge, the Himalayas bend sharply to the south
and spread along the eastern boundary of
India. They are known as the Purvanchal or
the Eastern hills and mountains. These hills
running through the north-eastern states are
mostly composed of strong sandstones which
are sedimentary rocks. Covered with dense
forests, they mostly run as parallel ranges
and valleys. The Purvanchal comprises the
• The names of the glaciers and passes
that lie in Great Himalayas
• The name of the states where highest peaks
are located.
• Location of Mussoorie, Nainital,
Ranikhet from your atlas and also name the state
where they are located.
Figure 2.5 : The Himalayas
The range lying to the south of the Himadri
forms the most rugged mountain system and
is known as Himachal or lesser Himalaya. The
ranges are mainly composed of highly
compressed and altered rocks. The altitude
varies between 3,700 and 4,500 metres and
the average width is of 50 Km. While the Pir
Panjal range forms the longest and the most
important range, the Dhaula Dhar and the
Mahabharat ranges are also prominent ones.
This range consists of the famous valley of
Kashmir, the Kangra and Kullu Valley in
Himachal Pradesh. This region is well known
for its hill stations.
The outer most range of the Himalayas is
called the Shiwaliks. They extend over a width
of 10-50 Km and have an altitude varying
between 900 and 1100 metres. These ranges
are composed of unconsolidated sediments
brought down by rivers from the main
Himalayan ranges located farther north. These
valleys are covered with thick gravel and
12 CONTEMPORARY INDIA
Patkai hills, the Naga hills, Manipur hills and
the Mizo hills.
The Northern Plain
The northern plain has been formed by the
interplay of the three major river systems,
namely– the Indus, the Ganga and the
Brahmaputra along with their tributaries. This
plain is formed of alluvial soil. The deposition
of alluvium in a vast basin lying at the foothills
of the Himalaya over millions of years, formed
this fertile plain. It spreads over an area of 7
lakh sq. km. The plain being about 2400 Km
long and 240 to 320 Km broad, is a densely
populated physiographic division. With a rich
soil cover combined with adequate water
supply and favourable climate it is
agriculturally a very productive part of India.
The rivers coming from northern
mountains are involved in depositional work.
In the lower course, due to gentle slope, the
velocity of the river decreases which results in
the formation of riverine islands.
The rivers in their lower course split into
numerous channels due to the deposition of silt.
These channels are known as distributaries.
The Northern Plain is broadly divided into
three sections. The Western part of the Northern
Plain is referred to as the Punjab Plains.
Formed by the Indus and its tributaries, the
larger part of this plain lies in Pakistan. The
Indus and its tributaries–the Jhelum, the
Chenab, the Ravi, the Beas and the Satluj
originate in the Himalaya. This section of the
plain is dominated by the doabs.
Figure 2.7 : The Northern Plains
Majuli, in the Brahmaputra
River is the largest inhabited riverine island in the
world.
Figure 2.6 : Mizo Hills
‘Doab’ is made up of two
words- ‘do’ meaning two and ‘ab’ meaning water.
Similarly ‘Punjab’ is also made up two words- ‘Punj’
meaning five and ‘ab’ meaning water.
The Ganga plain extends between Ghaggar
and Teesta rivers. It is spread over the states of
North India, Haryana, Delhi, U.P., Bihar, partly
Jharkhand and West Bengal to its East,
particularly in Assam lies the Brahmaputra plain.
The northern plains are generally deseribed
as flat land with no variations in its relief. It is
not true. These vast plains also have diverse
relief features. According to the variations in
relief features, the Northern plains can be
divided into four regions. The rivers, after
descending from the mountains deposit
pebbles in a narrow belt of about 8 to 16 km
in width lying parallel to the slopes of the
Shiwaliks. It is known as bhabar. All the
streams disappear in this bhabar belt. South
of this belt, the streams and rivers re-emerge
and create a wet, swampy and marshy region
known as terai. This was a thickly forested
region full of wildlife. The forests have been
cleared to create agricultural land and to settle
migrants from Pakistan after partition. Locate
Dudhwa National Park in this region.
The largest part of the northern plain is
formed of older alluvium. They lie above the
flood plains of the rivers and present a terrace
like feature. This part is known as bhangar.
PHYSICAL FEATURES OF INDIA 13
The Deccan Plateau is a triangular landmass
that lies to the south of the river Narmada. The
Satpura range flanks its broad base in the north
while the Mahadev, the Kaimur hills and the
Maikal range form its eastern extensions. Locate
these hills and ranges in the physical map of
India. The Deccan Plateau is higher in the west
and slopes gently eastwards. An extension of the
Plateau is also visible in the northeast– locally
known as the Meghalaya and Karbi-Anglong
Plateau. It is separated by a fault from the
Chotanagpur Plateau. Three Prominent hill
ranges from the west to east are the Garo, the
Khasi and the Jaintia Hills.
The Western Ghats and the Eastern Ghats
mark the western and the eastern edges of the
Deccan Plateau respectively. Western ghats lie
parallel to the western coast. They are continuous
and can be crossed through passes only. Locate
the Thal, Bhor and the Pal Ghats in the Physical
map of India.
The Western Ghats are higher than the
Eastern Ghats. Their average elevation is 900–
1600 metres as against 600 metres of the
Eastern Ghats. The Eastern Ghats stretch from
the Mahanadi Valley to the Nigiris in the south.
The Eastern Ghats are discontinuous and
irregular and dissected by rivers draining into
the Bay of Bengal. The Western Ghats cause
orographic rain by facing the rain bearing moist
winds to rise along the western slopes of the
Ghats. The Western Ghats are known by
different local names. The height of the Western
Ghats progressively increases from north to
south. The highest peaks include the Anai
Mudi (2,695metres) and the Doda Betta (2,637
metres). Mahendragiri (1,501 metres) is the
highest peak in the Eastern Ghats. Shevroy
Hills and the Javadi Hills are located to the
southeast of the Eastern Ghats. Locate the
famous hill stations of Udagamandalam,
popularly known as Ooty and the Kodaikanal.
One of the distinct features of the peninsular
plateau is the black soil area known as Decean
Trap. This is of volcanic origin hence the rocks
are igneous. Actually these rocks have
denuded over time and are responsible for the
formation of black soil. The Aravali Hills lie on
the western and northwestern margins of the
The soil in this region contains calcareous
deposites locally known as kankar. The newer,
younger deposits of the flood plains are called
khadar. They are renewed almost every year
and so are fertile, thus, ideal for intensive
agriculture.
The Peninsular Plateau
The Peninsular plateau is a tableland
composed of the old crystalline, igneous and
metamorphic rocks. It was formed due to the
breaking and drifting of the Gondwana land
and thus, making it a part of the oldest
landmass. The plateau has broad and shallow
valleys and rounded hills. This plateau
consists of two broad divisions, namely, the
Central Highlands and the Deccan Plateau.
The part of the Peninsular plateau lying to
the north of the Narmada river covering a
major area of the Malwa plateau is known as
the Central Highlands. The Vindhyan range
is bounded by the Central Highlands on the
south and the Aravalis on the northwest. The
further westward extension gradually merges
with the sandy and rocky desert of Rajasthan.
The flow of the rivers draining this region,
namely the Chambal, the Sind, the Betwa and
Ken is from southwest to northeast, thus
indicating the slope. The Central Highlands
are wider in the west but narrower in the east.
The eastward extensions of this plateau are
locally known as the Bundelkhand and
Baghelkhand. The Chotanagpur plateau
marks the further eastward extension,
drained by the Damodar river.
Figure 2.8 : A waterfall in Chotanagpur Plateau
14 CONTEMPORARY INDIA
peninsular plateau. These are highly eroded
hills and are found as broken hills. They extend
from Gujarat to Delhi in a southwest-northeast
direction.
The Indian Desert
The Indian desest lies towards the western
margins of the Aravali Hills. It is an undulating
sandy plain covered with sand dunes. This
region receives very low rainfall below 150 mm
per year. It has arid climate with low vegetatin
cover. Streams appear during the rainy
season. Soon after they disappear into the
sand as they do not have enough water to
reach the sea. Luni is the only large river in
this region.
The plain along the Bay of Bengal are wide
and level. In the northern part, it is referred to
as the Northern Circar, while the southern part
is known as the Coromandal Coast. Large
rivers such as the Mahanadi, the Godavari, the
Krishna and the Kaveri have farmed extensive
delta on this coast. Lake Chilika is an
important feature along the eastern coast.
The Chilika Lake is the
largest salt water lake in India. It lies in the state
of Orissa, to the south of the Mahanadi delta.
The Islands
You have already seen that India has a vast main
land. Besides this, the country has also two groups
of islands. Can you identify these island groups?
Figure 2.10 : The Coastal Plains
Figure 2.11 : An Island
Figure 2.9 : The Indian Desert
Barchans (crescent shaped dunes) cover
larger areas but longitudinal dunes become
more promiment near the Indo-Pakistan
boundary. If you visit Jaisalmer, you may go
to see a group of barchans.
The Coastal Plains
The Peninsular plateau is flanked by stretch
of narrow coastal strips, running along the
Arabian Sea on the west and the Bay of Bengal
on the east. The western coast, sandwiched
between the Western Ghats and the Arabian
Sea, is a narrow plain. It consists of three
sections. The northern part of the coast is called
the Konkan (Mumbai – Goa), the central stretch
is called the Kannad Plain while the southern
stretch is referred to as the Malabar coast.
Locate the Lakshadweep Islands group
lying close to the Malabar coast of Kerala. This
group of islands is composed of small coral
isalnds. Earlier they were known as Laccadive,
Minicoy and Amindive. In 1973 these were
PHYSICAL FEATURES OF INDIA 15
Corals
Coral polyps are short-lived microscopic
organisms, which live in colonies. They flourish
in shallow, mud free and warm waters. They
secrete hard rock like substance. The coral
secretion and their skeletons from coral deposits
in the form of reefs:. they are mainly of three
kinds: barrier reef. fringing reef and atolls. The
Great Barrier Reef of Australia is a good example
of the first kind of coral reefs. Atolls are circular
or horse shoe shaped coral reefs.
named as Lakshadweep. It covers small area
of 32 sq km. Kavaratti island is the
administrative headquarters of Lakshadweep.
This island group has great diversity of flora
and fauna. The Pitli island, which is
uninhabited, has a bird sanctuary.
starategic importance for the country. There
is great diversity of flora and fauna in this
group of islands too. These islands lie close to
equator and experience equatorial climate and
has thick forest cover.
1. Choose the right answer from the four alternatives given below.
(i) A landmass bounded by sea on three sides is referred to as
(a) Coast (c) Peninsula
(b) Island (d) none of the above
(ii) Mountain ranges in the eastern part of India forming its boundary with
Myanmar are collectively called as
(a) Himachal (c) Purvanchal
(b) Uttaranchal (d) none of the above
(iii) The western coastal strip, south of Goa is referred to as
(a) Coromandal (c) Kannad
(b) Konkan (d) Northern Circar
(iv) The highest peak in the Eastern Ghats is
(a) Anai Mudi (c) Mahendragiri
(b) Kanchenjunga (d) Khasi
2 Answer the following questions briefly.
(i) What are tectonic plates?
(ii) Which continents of today were part of the Gondwana land?
Now you see the elongated chain of islands
located in the Bay of Bengal extending from
north to south. These are Andaman and
Nicobar islands. They are bigger in size and
are more numerous and scattered. The entire
group of islands is divided into two broad
categories – The Andaman in the north and
the Nicobar in the south. It is believed that these
islands are an elevated portion of submarine
mountains. These island groups are of great
India’s only active volcano is
found on Barren island in Andaman and Nicobar
group of Islands.
A detailed account of the different
physiographic units highlights the unique
features of each region. It would, hoever,
be clear that each region complements the
other and makes the country richer in its
natural resources. The northern mountains
are the major sources of water and forest
wealth. The norhtern plains are the
granaries of the country. They provide the
base for early civilisations. The plateau is a
storehouse of minerals, which has played a
crucial role in the industrialisation of the
country. The coastal region and island
groups provide sites for fishing and port
activities. Thus, the diverse physical
features of the land have immense future
possibilities of development.
EXERCISE
16 CONTEMPORARY INDIA
(iii) What is the bhabar?
(iv) Name the three major divisions of the Himalayas from north to south.
(v) Which plateau lies between the Aravali and the Vindhyan ranges?
(vi) Name the island group of India having coral origin.
3. Distinguish between
(i) Converging and diverging tectonic plates
(ii) Bhangar and Khadar
(iii) Western Ghats and Eastern Ghats
4. Describe how the Himalayas were formed.
5. Which are the major physiographic divisions of India? Contrast the relief of the
Himalayan region with that of the Peninsular plateau.
6. Give an account of the Northern Plains of India.
7. Write short notes on the following.
(i) The Indian Desert
(ii) The Central Highlands
(iii) The Island groups of India
MAP SKILLS
On an outline map of India show the following.
(i) Mountain and hill ranges – the Karakoram, the Zaskar, the Patkai Bum, the
Jaintia, the Vindhya range, the Aravali, and the Cardamom hills.
(ii) Peaks – K2, Kanchenjunga, Nanga Parbat and the Anai Mudi.
(iii) Plateaus, Chotanagpur and Malwa
(iv) The Indian Desert, Western Ghats, Lakshadweep Islands
PROJECT/ACTIVITY
Locate the peaks, passes, ranges, plateaus, hills, and duns hidden in the puzzle.
Try to find where these features are located. You may start your search horizontally,
vertically or diagonally.


Water Divide
Sream A
Sream B
Figure 3.1 : Water Divide
DRAINAGE
The term drainage describes the river
system of an area. Look at the physical
map. You will notice that small streams
flowing from different directions come together
to form the main river, which ultimately drains
into a large water body such as a lake or a sea
or an ocean. The area drained by a single river
system is called a drainage basin. A closer
observation on a map will indicate that any
elevated area, such as a mountain or an upland,
separates two drainage basins. Such an upland
is known as a water divide (Figure 3.1).
The world’s largest drainage
basin is of the Nile river in Egypt
Figure 3.2 : A Gorge
subcontinent. Accordingly, the Indian rivers
are divided into two major groups:
• the Himalayan rivers; and
• the Peninsular rivers.
Apart from originating from the two major
physiographic regions of India, the Himalayan
and the Peninsular rivers are different from
each other in many ways. Most of the
Himalayan rivers are perennial. It means
that they have water throughout the year.
These rivers receive water from rain as well
as from melted snow from the lofty
mountains. The two major Himalayan rivers,
the Indus and the Brahmaputra originate
from the north of the mountain ranges. They
have cut through the mountains making
gorges. The Himalayan rivers have long
courses from their source to the sea. They
perform intensive erosional activity in their
upper courses and carry huge loads of silt
and sand. In the middle and the lower courses,
these rivers form meanders, oxbow lakes, and
many other depositional features in their
3
• Which river has the largest basin in India?
DRAINAGE SYSTEMS IN INDIA
The drainage systems of India are mainly
controlled by the broad relief features of the
18 CONTEMPORARY INDIA
floodplains. They also have well-developed
deltas (Figure 3.3).
A large number of the Peninsular rivers are
seasonal, as their flow is dependent on rainfall.
During the dry season, even the large rivers
have reduced flow of water in their channels.
The Peninsular rivers have shorter and
shallower courses as compared to their
Himalayan counterparts. However, some of
them originate in the central highlands and flow
towards the west. Can you identify two such
large rivers? Most of the rivers of peninsular
India originate in the Western Ghats and flow
towards the Bay of Bengal.
The Himalayan Rivers
The major Himalayan rivers are the Indus, the
Ganga and the Brahmaputra. These rivers are
long, and are joined by many large and
important tributaries. A river alongwith its
tributaries may be called a river system.
The Indus River System
The river Indus rises in Tibet, near Lake
Mansarowar. Flowing west, it enters India in the
Ladakh district of Jammu and Kashmir. It forms
a picturesque gorge in this part. Several
tributaries, the Zaskar, the Nubra, the Shyok
and the Hunza, join it in the Kashmir region.
The Indus flows through Baltistan and Gilgit and
emerges from the mountains at Attock. The
Satluj, the Beas, the Ravi, the Chenab and the
Jhelum join together to enter the Indus near
Mithankot in Pakistan. Beyond this, the Indus
flows southwards eventually reaching the
Arabian Sea, east of Karachi. The Indus plain
has a very gentle slope. With a total length of
2900 km, the Indus is one of the longest rivers
Source of River
Upper Course
Middle Course
Ox-Bow Lake
Lower
Course
Meander
Delta
Figure 3.3 : Some Features Made by Rivers
Drainage Patterns
The streams within a drainage basin form
certain patterns, depending on the slope
of land, underlying rock structure as well
as the climatic conditions of the area.
These are dendritic, trellis, rectangular,
and radial patterns. The dendritic pattern
develops where the river channel follows
the slope of the terrain. The stream with
its tributaries resembles the branches of
a tree, thus the name dendritic. A river
joined by its tributaries, at approximately
right angles, develops a trellis pattern. A
trellis drainage pattern develops where
hard and soft rocks exist parallel to each
other. A rectangular drainage pattern
develops on a strongly jointed rocky
terrain. The radial pattern develops when streams flow in different
directions from a central peak or dome like structure.
A combination of several patterns may be found in the same drainage basin.
DRAINAGE 19
Figure 3.4 : Major Rivers and Lakes
20 CONTEMPORARY INDIA
of the world. A little over a third of the Indus
basin is located in India in the states of Jammu
and Kashmir, Himachal Pradesh and the Punjab
and the rest is in Pakistan.
• According to the regulations
of the Indus Water Treaty (1960), India can use
only 20 per cent of the total water carried by Indus
river system. This water is used for irrigation in
the Punjab, Haryana and the southern and
western parts of Rajasthan.
The Ganga River System
The headwaters of the Ganga, called the
‘Bhagirathi’ is fed by the Gangotri Glacier and
joined by the Alaknanda at Devaprayag in
Uttaranchal. At Haridwar the Ganga emerges
from the mountains on to the plains.
The main tributaries, which come from the
peninsular uplands, are the Chambal, the
Betwa and the Son. These rise from semi arid
areas, have shorter courses and do not carry
much water in them. Find out where and how
they ultimately join the Ganga.
Enlarged with the waters from its right and
left bank tributaries, the Ganga flows
eastwards till Farakka in West Bengal. This is
the northernmost point of the Ganga delta. The
river bifurcates here; the Bhagirathi-Hooghly
(a distributary) flows southwards through the
deltaic plains to the Bay of Bengal. The
mainstream, flows southwards into
Bangladesh and is joined by the Brahmaputra.
Further down stream, it is known as the
Meghna. This mighty river, with waters from
the Ganga, and the Brahmaputra, flows into
the Bay of Bengal. The delta formed by these
rivers is known as the Sunderban delta.
• The Sundarban Delta derived
its name from the Sundari tree which grows well in
marshland.
• It is the world’s largest and fastest growing delta.
It is also the home of Royal Bengal tiger.
The length of the Ganga is over 2500 km.
Look at figure 3.4; can you identify the type of
drainage pattern formed by the Ganga river
system? Ambala is located on the water divide
between th Indus and the Ganga river systems.
The plains from Ambala to the Sunderban
stretch over nearly 1800 km, but the fall in its
slope is hardly 300 metres. In other words,
there is a fall of just one metre for every 6 km.
Therefore, the river develops large meanders.
The Brahmaputra River System
The Brahmaputra rises in Tibet east of
Mansarowar lake very close to the sources of
the Indus and the Satluj. It is slightly longer
than the Indus, and most of its course lies
outside India. It flows eastwards parallel to
the Himalayas. On reaching the Namcha
Barwa (7757 m), it takes a ‘U’ turn and enters
India in Arunachal Pradesh through a gorge.
Here, it is called the Dihang and it is joined
by the Dibang, the Lohit, the Kenula and
Figure 3.5 : Confluence of Bhagirathi and Alaknanda at
Devaprayag
The Ganga is joined by many tributaries
from the Himalayas, a few of them being major
rivers such as the Yamuna, the Ghaghara, the
Gandak and the Kosi. The river Yamuna rises
from the Yamunotri Glacier in the Himalayas.
It flows parallel to the Ganga and as a right
bank tributary, meets the Ganga at Allahabad.
The Ghaghara, the Gandak and the Kosi rise
in the Nepal Himalaya. They are the rivers,
which flood parts of the northern plains every
year, causing widespread damage to life and
property but enriching the soil for the extensive
agricultural lands.
DRAINAGE 21
many other tributaries to form the
Brahmaputra in Assam.
• Brahmaputra is known as
the Tsang Po in Tibet and Jamuna in Bangladesh.
In Tibet the river carries a smaller volume of
water and less silt as it is a cold and a dry area.
In India it passes through a region of high rainfall.
Here the river carries a large volume of water and
considerable amount of silt. The Brahmaputra
has a braided channel in its entire length in
Assam and forms many riverine islands. Do you
remember the name of the world’s largest riverine
island formed by the Brahmaputra?
Every year during the rainy season, the
river overflows its banks, causing widespread
devastation due to floods in Assam and
Bangladesh. Unlike other north Indian rivers
the Brahmaputra is marked by huge deposits
of silt on its bed causing the river bed to rise.
The river also shifts its channel frequently.
The Peninsular Rivers
The main water divide in Peninsular India is
formed by the Western Ghats, which runs from
north to south close to the western coast. Most
of the major rivers of the Peninsula such as
the Mahanadi, the Godavari, the Krishna and
the Kaveri flow eastwards and drain into the
Bay of Bengal. These rivers make deltas at
their mouths. There are numerous small
streams flowing west of the Western Ghats.
The Narmada and the Tapi are the only long
rivers, which flow west and make esturies. The
drainage basins of the peninsular rivers are
comparitevely small in size.
The Narmada Basin
The Narmada rises in the Amarkantak hills
in Madhya Pradesh. It flows towards the west
in a rift valley formed due to faulting. On its
way to the sea, the Narmada creates many
picturesque locations. The ‘Marble rocks’,
near Jabalpur where the Narmada flows
through a deep gorge, and the ‘Dhuadhar
falls’ where the river plunges over steep rocks,
are some of the notable ones.
All the tributaries of the Narmada are very
short and most of these join the main stream
at right angles. The Narmada basin covers parts
of Madhya Pradesh and Gujarat.
The Tapi Basin
The Tapi rises in the Satpura ranges, in the
Betul district of Madhya Pradesh. It also flows
in a rift valley parallel to the Narmada but it is
much shorter in length. Its basin covers parts
of Madhya Pradesh, Gujarat and Maharashtra.
The coastal plains between western ghats
and the Arabian sea are very narrow. Hence,
the coastal rivers are short. The main west
flowing rivers are Sabarmati, Mahi,
Bharathpuzha and Periyar. Find out the states
in which these rivers drain the water.
The Godavari Basin
The Godavari is the largest Peninsular river.
It rises from the slopes of the Western Ghats
in the Nasik district of Maharashtra. Its
length is about 1500 km. It drains into the
Bay of Bengal. Its drainage basin is also the
largest among the peninsular rivers. The
basin covers parts of Maharashtra (about 50
per cent of the basin area lies in Maharashtra),
Madhya Pradesh, Orissa and Andhra
Pradesh. The Godavari is joined by a number
of tributaries such as the Purna, the Wardha,
the Pranhita, the Manjra, the Wainganga and
the Penganga. The last three tributaries are
very large. Because of its length and the
area it covers, it is also known as the
‘Dakshin Ganga’.
The Mahanadi Basin
The Mahanadi rises in the highlands of
Chhattisgarh. It flows through Orissa to reach
the Bay of Bengal. The length of the river is
about 860 km. Its drainage basin is shared by
Maharashtra, Chhattisgarh, Jharkhand,
and Orissa.
The Krishna Basin
Rising from a spring near Mahabaleshwar, the
Krishna flows for about 1400 km and reaches
the Bay of Bengal. The Tungabhadra, the
Koyana, the Ghatprabha, the Musi and the
Bhima are some of its tributaries. Its drainage
22 CONTEMPORARY INDIA
basin is shared by Maharasthra, Karnataka
and Andhra Pradesh.
The Kaveri Basin
The Kaveri rises in the Brahmagri range of the
Western Ghats and it reaches the Bay of Bengal
in south of Cuddalore, in Tamil Nadu. Total
length of the river is about 760 km. Its main
tributaries are Amravati, Bhavani, Hemavati
and Kabini. Its basin drains parts of
Karnataka, Kerala and Tamil Nadu.
• The river Kaveri makes the
second biggest waterfall in India. It is known as
Sivasamudram. The fall supplies hydroelectric
power to Mysore, Bangalore and the Kolar Gold
Field.
• The name of the biggest waterfall
in India.
Beside these major rivers, there are some
smaller rivers flowing towards the east. The
Damoder, the Brahmani, the Baitarni and the
Subarn rekha are some notable examples.
Locate them in you atlas.
• 71 per cent of the world’s
surface is covered with water, but 97 per cent of
that is salt water.
• Of the 3 per cent that is available as freshwater,
three quarters of it is trapped as ice.
LAKES
You may be familiar with the valley of Kashmir
and the famous Dal Lake, the house boats and
shikaras, which attract thousands of tourists
every year. Similarly, you may have visited
some other tourist spot near a lake and enjoyed
boating, swimming and other water games.
Imagine that if Srinagar, Nainital and other
tourists places did not have a lake would they
have been as attractive as they are today? Have
you ever tried to know the importance of lakes
in making a place attractive to tourists? Apart
from attraction for tourists lakes are also useful
to human beings in many ways.
• Lakes of large extent are called the seas,
like the Caspian, the Dead and the Aral seas.
India has many lakes. These differ from
each other in the size, and other
characteristics. Most lakes are permanent;
some contain water only during the rainy
season, like the lakes in the basins of inland
drainage of semi-arid regions. There are some
of the lakes which are the result of the action
of glaciers and ice sheets, while the others
have been formed by wind, river action, and
human activities.
A meandering river across a flood plain
forms cut-offs that later develop into ox-bow
lakes. Spits and bars form lagoons in the
coastal areas, eg the Chilika lake, the Pulicat
lake, the Kolleru lake. Lakes in the region of
inland drainage are sometimes seasonal; for
example, the Sambhar lake in Rajasthan, which
is a salt water lake. Its water is used for
producing salt.
Most of the fresh water lakes are in the
Himalayan region. They are of glacial origin.
In other words, they formed when glaciers
dug out a basin, which was later filled with
snowmelt. The Wular lake in Jammu and
Kashmir, in contrast, is the result of the
tectonic activity. It is the largest freshwater
lake in India. The Dal lake, Bhimtal, Nainital,
Loktak and Barapani are some other
important fresh water lakes.
Apart from natural lakes, the damming of
the rivers for the generation of hydel power has
also led to the formation of Lakes such as Guru
Gobind Sagar (Bhakra Nangal Project).
Figure 3.6 : Loktak Lake
DRAINAGE 23
Activity
Make a list of natural and artifcial
lakes with the help of the atlas.
Lakes are of great value to human beings.
A lake helps to regulate the flow of a river.
During heavy rainfall, it prevents flooding and
during the dry season, it helps to maintain
an even flow of water. Lakes can also be used
for developing hydel power. They moderate the
climate of the surroundings; maintain the
aquatic ecosystem, enhance natural beauty,
help develop tourism and provide recreation.
ROLE OF RIVERS IN THE ECONOMY
Rivers have been of fundamental importance
throughout the human history. Water from the
rivers is a basic natural resource, essential for
various human activities. Therefore, the river
banks have attracted settlers from ancient
times. These settlements have now become big
cities. Make a list of cities in your state which
are located on the bank of a river.
Using rivers for irrigation, navigation,
hydro-power generation is of special
significance – particularly to a country like
India, where agriculture is the major source
of livelihood of the majority of its population.
RIVER POLLUTION
The growing domestic, municipal, industrial
and agricultural demand for water from rivers
naturally affects the quality of water. As a
result, more and more water is being drained
out of the rivers reducing their volume. On
the other hand, a heavy load of untreated
sewage and industrial effluents are emptied
into the rivers. This affects not only the quality
of water but also the self-cleansing capacity
of the river. For example, given the adequate
streamflow, the Ganga water is able to dilute
and assimilate pollution loads within 20 km
of large cities. But the increasing
urbanisation and industrialisation do not
allow it to happen and the pollution level of
many rivers has been rising. Concern over
rising pollution in our rivers led to the
launching of various action plans to clean the
rivers. Have you heard about such action
plans? How does our health get affected by
polluted river water? Think about “ life of
human beings without fresh water” Arrange
a debate on this topic in the class.
National River Conservation Plan (NRCP)
The activities of Ganga Action Plan (GAP)
phase-I, initiated in 1985, were declared
closed on 31st March 2000. The Steering
Committee of the National River
Conservation Authority reviewed the
progress of the GAP and necessary correction
on the basis of lessons learnt and
experiences gained from GAP Phase-I. These
have been applied to the major polluted
rivers of the country under the NRCP.
The Ganga Action Plan (GAP) Phase-II,
has been merged with the NRCP. The
expanded NRCP now covers 152 towns located
along 27 interstate rivers in 16 states. Under
this action plan, pollution abatement works
are being taken up in 57 towns. A total of
215 schemes of pollution abatement have
been sanctioned. So far, 69 schemes have
been completed under this action plan. A
million litres of sewage is targeted to be
intercepted, diverted and treated.
1. Choose the right answer from the four alternatives given below.
(i) Which one of the following describes the drainage patterns resembling the
branches of a tree?
(a) Radial (c) Centrifugal
(b) Dendritic (d) Trellis
EXERCISE
24 CONTEMPORARY INDIA
(ii) In which of the following states is the Wular lake located?
(a) Rajasthan (c) Punjab
(b) Uttar Pradesh (d) Jammu and Kashmir
(iii) The river Narmada has its source at
(a) Satpura (c) Amarkantak
(b) Brahmagiri (d) Slopes of the Western ghats
(iv) Which one of the following lakes is a salt water lake?
(a) Sambhar (c) Wular
(b) Dal (d) Gobind Sagar
(v) Which one of the following is the longest river of the Peninsular India?
(a) Narmada (c) Godavari
(b) Krishma (d) Mahanadi
(vi) Which one amongst the following rivers flows through a rift valley?
(a) Damodar (c) Krishna
(b) Tungabhadra (d) Tapi
2. Answer the following questions briefly.
(i) What is meant by a water divide? Give an example.
(ii) Which is the largest river basin in India?
(iii) Where do the rivers Indus and Ganga have their origin?
(iv) Name the two headstreams of the Ganga. Where do they meet to form the Ganga?
(v) Why does the Brahmaputra in its Tibetan part have less silt, despite a
longer course?
(vi) Which two Peninsular rivers flow through trough?
(vii) State some economic benefits of rivers and lakes.
3. Below are given names of a few lakes of India. Group them under two categories
– natural and created by human beings.
(a) Wular (b) Dal
(c) Nainital (d) Bhimtal
(e) Gobind Sagar (f) Loktak
(g) Barapani (h) Chilika
(i) Sambhar (j) Rana Pratap Sagar
(k) Nizam Sagar (l) Pulicat
(m) Nagarjuna Sagar (n) Hirakund
4. Discuss the significant difference between the Himalayan and the Peninsular
rivers.
5. Compare the east flowing and the west flowing rivers of the Peninsular plateau.
6. Why are rivers important for the country’s economy?
Map Skills
(i) On an outline map of India mark and label the following rivers: Ganga,
Satluj, Damodar, Krishna, Narmada, Tapi, Mahanadi, and Brahmaputra.
(ii) On an outline map of India mark and label the following lakes: Chilika,
Sambhar, Wular, Pulicat, Kolleru.
DRAINAGE 25
Project/Activity
Solve this crossword puzzle with the help of given clues.
Across
1. Nagarjuna Sagar is a river valley project. Name the river?
2. The longest river of India.
3. The river which originates from a place known as Beas Kund.
4. The river which rises in the Betul district of MP and flows westwards.
5. The river which is known as the “Sorrow” of Bihar.
6. The river on which the reservior for India Gandhi canal has been built.
7. The river whose source lies near Rohtang Pass.
8. The longest river of Peninsular India?
Down
9. A tributary of Indus originating from Himachal Pradesh.
10. The river flowing through fault, drains into the Arabian Sea.
11. A river of south India, which receives rain water both in summer and winter.
12. A river which flows through Ladakh, Gilgit and Pakistan.
13. An important river of the Indian desert.
14. The river which joins Chenab in Pakistan.
15. A river which rises at Yamunotri glacier.


In the last two chapters you have read about
the landforms and the drainage of
our country. These are the two of the three
basic elements that one learns about the natural
environment of any area. In this chapter you
will learn about the third, that is, the
atmospheric conditions that prevail over our
country. Why do we wear woollens in December
or why it is hot and uncomfortable in the month
of May, and why it rains in June - July? The
answers to all these questions can be found out
by studying about the climate of India.
Climate refers to the sum total of weather
conditions and variations over a large area for
a long period of time (more than thirty years).
Weather refers to the state of the atmosphere
over an area at any point of time. The elements
of weather and climate are the same, i.e.
temperature, atmospheric pressure, wind,
humidity and precipitation. You may have
observed that the weather conditions fluctuate
very often even within a day. But there is some
common pattern over a few weeks or months,
i.e. days are cool or hot, windy or calm, cloudy
or bright, and wet or dry. On the basis of the
generalised monthly atmospheric conditions,
the year is divided into seasons such as winter,
summer or rainy seasons.
The world is divided into a number of
climatic regions. Do you know what type of
climate India has and why it is so? We will
learn about it in this chapter.
• The word monsoon is
derived from the Arabic word ‘mausim’ which
literally means season.
• ‘Monsoon’ refers to the seasonal reversal in the
wind direction during a year.
CLIMATE
The climate of India is described as the
‘monsoon’ type. This type of climate is found
mainly in the south and the Southeast Asia.
Despite an overall unity in the general pattern,
there are perceptible regional variations in
climatic conditions within the country. Let us
take two important elements – temperature and
precipitation, and examine how they vary from
place to place and season to season.
In summer, the mercury occasionally
touches 50°C in some parts of the Rajasthan
desert, whereas it may be around 20°C in
Pahalgam in Jammu and Kashmir. On a winter
night, temperature at Drass in Jammu and
Kashmir may be as low as minus 45°C.
Tiruvananthapuram, on the other hand, may
have a temperature of 20°C.
In certain places there is a
wide difference between day and night
temperatures. In the Thar Desert the day
temperature may rise to 50°C, and drop down
to near 15°C the same night. On the other hand,
there is hardly any difference in day and night
temperatures in the Andaman and Nicobar
islands or in Kerala.
Let us now look at precipitation. There are
variations not only in the form and types of
precipitation but also in its amount and the
seasonal distribution. While precipitation is
mostly in the form of snowfall in the upper parts
of Himalayas, it rains over the rest of the
country. The annual precipitation varies from
over 400 cm in Meghalaya to less than 10 cm
in Ladakh and western Rajasthan. Most parts
of the country receive rainfall from June to
September. But some parts like the Tamil Nadu
4
CLIMATE 27
• Why most of the world’s deserts are
located in the western margins of continents in the
subtropics?
Finally, relief too plays a major role in
determining the climate of a place. High
mountains act as barriers for cold or hot winds;
they may also cause precipitation if they are high
enough and lie in the path of rain-bearing winds.
The leeward side of mountains remains dry.
FACTORS AFFECTING INDIA’S CLIMATE
Latitude
The Tropic of Cancer passes through the middle
of the country from the Rann of Kuchchh in the
west to Mizoram in the east. Almost half of the
country, lying south of the Tropic of Cancer,
belongs to the tropical area. All the remaining
area, north of the Tropic, lies in the sub-tropics.
Therefore, India’s climate has characteristics of
tropical as well as subtropical climates.
Altitude
India has mountains to the north, which have
an average height of about 6,000 metres. India
also has a vast coastal area where the
maximum elevation is about 30 metres. The
Himalayas prevent the cold winds from Central
Asia from entering the subcontinent. It is
because of these mountains that this
subcontinent experiences comparatively
milder winters as compared to central Asia.
Pressure and Winds
The climate and associated weather conditions
in India are governed by the following
atmospheric conditions:
• Pressure and surface winds;
• Upper air circulation; and
• Western cyclonic disturbances and
tropical cyclones.
India lies in the region of north easterly
winds. These winds originate from the
subtropical high-pressure belt of the northern
coast get most of its rain during October and
November.
In general, coastal areas experience less
contrasts in temperature conditions. Seasonal
contrasts are more in the interior of the
country. There is decrease in rainfall generally
from east to west in the Northern Plains. These
variations have given rise to variety in lives of
people – in terms of the food they eat, the
clothes they wear and also the kind of houses
they live in.
• Why the houses in Rajasthan have thick
walls and flat roofs?
• Why is it that the houses in the Tarai region and
in Goa and Mangalore have sloping roofs?
• Why houses in Assam are built on stilts?
CLIMATIC CONTROLS
There are six major controls of the climate of
any place. They are: latitude, altitude,
pressure and wind system, distance from
the sea (continentality), ocean currents and
relief features.
Due to the curvature of the earth, the
amount of solar energy received varies
according to latitude. As a result, air
temperature decreases from the equator
towards the poles. As one goes from the
surface of the earth to higher altitudes, the
atmosphere becomes less dense and
temperature decreases. The hills are therefore
cooler during summers. The pressure and
wind system of any area depend on the
latitude and altitude of the place. Thus it
influences the temperature and rainfall
pattern. The sea exerts a moderating influence
on climate: As the distance from the sea
increases, its moderating influence decreases
and the people experience extreme weather
conditions. This condition is known as
continentality (i.e. very hot during summers
and very cold during winters). Ocean currents
along with onshore winds affect the climate of
the coastal areas, For example, any coastal
area with warm or cold currents flowing past
it, will be warmed or cooled if the winds are
onshore.
28 CONTEMPORARY INDIA
hemisphere. They blow south, get deflected to
the right due to the Coriolis force, and move
on towards the equatorial low-pressure area.
Generally, these winds carry very little
moisture as they originate and blow over land.
Therefore, they bring little or no rain. Hence,
India should have been an arid land, but, it is
not so. Let us see why?
Coriolis force: An apparent force caused by the earth’s
rotation. The Coriolis force is responsible for deflecting
winds towards the right in the northern hemisphere
and towards the left in the southern hemisphere. This
is also known as ‘Ferrel’s Law’.
The pressure and wind conditions over
India are unique. During winter, there is a
high-pressure area north of the Himalayas.
Cold dry winds blow from this region to the
low-pressure areas over the oceans to the
south. In summer, a low-pressure area
develops over interior Asia as well as over
northwestern India. This causes a complete
reversal of the direction of winds during
summer. Air moves from the high-pressure
area over the southern Indian Ocean, in a
south-easterly direction, crosses the equator,
and turns right towards the low-pressure areas
over the Indian subcontinent. These are known
as the Southwest Monsoon winds. These winds
blow over the warm oceans, gather moisture
and bring widespread rainfall over the
mainland of India.
The upper air circulation in this region is
dominated by a westerly flow. An important
component of this flow is the jet stream.
These jet streams are located approximately
over 27°-30° north latitude, therefore, they are
known as subtropical westerly jet streams. Over
India, these jet streams blow south of the
Himalayas, all through the year except in
summer. The western cyclonic disturbances
experienced in the north and north-western parts
of the country are brought in by this westerly
flow. In summer, the subtropical westerly jet
stream moves north of the Himalayas with the
apparent movement of the sun. An easterly jet
stream, called the tropical easterly jet stream
blows over peninsular India, approximately over
14°N during the summer months.
Western Cyclonic Disturbances
The western cyclonic disturbances are weather
phenomena of the winter months brought in by the
westerly flow from the Mediterranean region. They
usually influence the weather of the north and
north-western regions of India. Tropical cyclones
occur during the monsoon as well as in October -
November, and are part of the easterly flow. These
distrurbances affect the coastal regions of the
country. Have you read or heard about the
disasters caused by them on Orissa and Andhra
Pradesh coast?
THE INDIAN MONSOON
The climate of India is strongly influenced by
monsoon winds. The sailors who came to India
in historic times were one of the first to have
noticed the phenomenon of the monsoon. They
benefited from the reversal of the wind system
as they came by sailing ships at the mercy of
winds. The Arabs, who had also come to India
as traders named this seasonal reversal of the
wind system ‘monsoon’.
Figure 4.1 : Arrival of Monsoon
Jet stream: These are a narrow belt of high
altitude (above 12,000 m) westerly winds in the
troposphere. Their speed varies from about 110
km/h in summer to about 184 km/h in winter.
A number of separate jet streams have been
identified. The most constant are the mid-latitude
and the sub tropical jet stream.
CLIMATE 29
Figure 4.3 : Atmospheric Conditions over the Indian Subcontinent in the Month of June
Figure 4.2 : Atmospheric Conditions over the Indian Subcontinent in the Month of January
30 CONTEMPORARY INDIA
conditions is known as the Southern
Oscillation or SO. The difference in pressure
over Tahiti (Pacific Ocean, 18°S/149°W) and
Darwin in northern Australia (Indian Ocean,
12°30’S/131°E) is computed to predict the
intensity of the monsoons. If the pressure
differences were negative, it would mean below
average and late monsoons. A feature connected
with the SO is the El Nino, a warm ocean current
that flows past the Peruvian Coast, in place of
the cold Peruvian current, every 2 to 5 years.
The changes in pressure conditions are
connected to the El Nino. Hence, the
phenomenon is referred to as ENSO (El Nino
Southern Oscillations).
El Nino: This is a name given to the periodic
development of a warm ocean current along the
coast of Peru as a temporary replacement of the
cold Peruvian current. ‘El Nino’ is a Spanish word
meaning ‘the child’, and refers to the baby Christ,
as this current starts flowing during Christmas.
The presence of the El Nino leads to an increase
in sea-surface temperatures and weakening of
the trade winds in the region.
THE ONSET OF THE MONSOON AND WITHDRAWAL
The Monsoon, unlike the trades, are not steady
winds but are pulsating in nature, affected by
different atmospheric conditions encountered
by it, on its way over the warm tropical seas.
The duration of the monsoon is between 100-
120 days from early June to mid-September.
Around the time of its arrival, the normal
rainfall increases suddenly and continues
constantly for several days. This is known as
the ‘burst’ of the monsoon, and can be
distinguished from the pre-monsoon showers.
The monsoon arrives at the southern tip of the
Indian peninsula generally by the first week of
June. Subsequently, it divides into two – the
Arabian Sea branch and the Bay of Bengal
branch. The Arabian Sea branch reaches
Mumbai about ten days later on
approximately the 10th of June. This is a fairly
rapid advance. The Bay of Bengal branch also
advances rapidly and arrives in Assam in the
first week of June. The lofty mountains causes
the monsoon winds to deflect towards the west
The monsoons are experienced in the
tropical area roughly between 20° N and 20°
S. To understand the mechanism of the
monsoons, the following facts are important.
(a) The differential heating and cooling of
land and water creates low pressure on the
landmass of India while the seas around
experience comparatively high pressure.
(b) The shift of the position of Inter Tropical
Convergence Zone (ITCZ) in summer, over
the Ganga plain (this is the equatorial trough
normally positioned about 5°N of the
equator – also known as the monsoontrough
during the monsoon season).
(c) The presence of the high-pressure area,
east of Madagascar, approximately at
20°S over the Indian Ocean. The intensity
and position of this high-pressure area
affects the Indian Monsoon.
(d) The Tibetan plateau gets intensely
heated during summer, which results in
strong vertical air currents and the
formation of high pressure over the plateau
at about 9 km above sea level.
(e) The movement of the westerly jet stream
to the north of the Himalayas and the
presence of the tropical easterly jet
stream over the Indian peninsula during
summer.
Inter Tropical Convergence Zone
The Inter Tropical Convergence Zone (ITCZ,) is a
broad trough of low pressure in equatorial
latitudes. This is where the northeast and the
southeast trade winds converge. This
convergence zone lies more or less parallel to
the equator but moves north or south with the
apparent movement of the sun.
Apart from this, it has also been noticed that
changes in the pressure conditions over the
southern oceans also affect the monsoons.
Normally when the tropical eastern south Pacific
Ocean experiences high pressure, the tropical
eastern Indian Ocean experiences low pressure.
But in certain years, there is a reversal in the
pressure conditions and the eastern Pacific has
lower pressure in comparison to the eastern
Indian Ocean. This periodic change in pressure
CLIMATE 31
over the Ganga plains. By mid-June the
Arabian Sea branch of the monsoon arrives
over Saurashtra-Kuchchh and the central part
of the country. The Arabian Sea and the Bay
of Bengal branches of the monsoon merge over
the northwestern part of the Ganga plains.
Delhi generally receives the monsoon showers
from the Bay of Bengal branch by the end of
June (tentative date is 29th of June). By the first
week of July, western Uttar Pradesh, Punjab,
Haryana and eastern Rajasthan experience the
monsoon. By mid-July, the monsoon reaches
Himachal Pradesh and the rest of the country
(Figure 4.3).
Withdrawal or the retreat of the monsoon
is a more gradual process (Figure 4.4). The
withdrawal of the monsoon begins in
northwestern states of India by early
September. By mid-October, it withdraws
completely from the northern half of the
peninsula. The withdrawal from the southern
half of the peninsula is fairly rapid. By early
December, the monsoon has withdrawn from
the rest of the country.
The islands receive the very first monsoon
showers, progressively from south to north,
from the first week of April to the first week of
May. The withdrawal, takes place progressively
from north to south from the first week of
December to the first week of January. By this
time the rest of the country is already under
the influence of the winter monsoon.
THE SEASONS
The monsoon type of climate is characterised
by a distinct seasonal pattern. The weather
conditions greatly change from one season to
the other. These changes are particularly
noticeable in the interior parts of the country.
The coastal areas do not experience much
variation in temperature though there is
variation in rainfall pattern. How many seasons
are experienced in your place? Four main
seasons can be identified in India – the cold
weather season, the hot weather season, the
advancing monsoon and the retreating
monsoon with some regional variations.
The Cold Weather Season (Winter)
The cold weather season begins from mid-
November in northern India and stays till
February. December and January are the coldest
months in the northern part of India. The
temperature decreases from south to the north.
The average temperature of Chennai, on the
eastern coast, is between 24° - 25° Celsius, while
in the northern plains, it ranges between 10° -
15° Celsius. Days are warm and nights are cold.
Frost is common in the north and the higher
slopes of the Himalayas experience snowfall.
During this season, the northeast trade
winds prevail over the country. They blow from
land to sea and hence, for most part of the
country, it is a dry season. Some amount of
rainfall occurs on the Tamil Nadu coast from
these winds as, here they blow from sea to land.
In the northern part of the country, a feeble
high-pressure region develops, with light winds
moving outwards from this area. Influenced by
the relief, these winds blow through the Ganga
valley from the west and the northwest. The
weather is normally marked by clear sky, low
temperatures and low humidity and feeble,
variable winds.
A characteristic feature of the cold weather
season over the northern plains is the inflow of
cyclonic disturbances from the west and the
northwest. These low-pressure systems,
originate over the Mediterranean Sea and
western Asia and move into India, along with
the westerly flow. They cause the much-needed
winter rains over the plains and snowfall in the
mountains. Although the total amount of
winter rainfall locally known as ‘mahawat’ is
small, they are of immense importance for the
cultivation of ‘rabi’ crops.
The peninsular region does not have a welldefined
cold season. There is hardly any
noticeable seasonal change in temperature
pattern during winters due to the moderating
influence of the sea.
The Hot Weather Season (Summer)
Due to the apparent northward movement of the
sun, the global heat belt shifts northward. As
such, from March to May, it is hot weather season
32 CONTEMPORARY INDIA
Figure 4.4 : Advancing Monsoon
CLIMATE 33
in India. The influence of the shifting of the heat
belt can be seen clearly from temperature
recordings taken during March-May at different
latitudes. In March, the highest temperature is
about 38° Celsius, recorded on the Deccan
plateau. In April, temperatures in Gujarat and
Madhya Pradesh are around 42° Celsius. In May,
temperature of 45° Celsius is common in the
northwestern parts of the country. In peninsular
India, temperatures remain lower due to the
moderating influence of the oceans.
The summer months experience rising
temperature and falling air pressure in the
northern part of the country. Towards the end
of May, an elongated low-pressure area
develops in the region extending from the Thar
Desert in the northwest to Patna and
Chotanagpur plateau in the east and
southeast. Circulation of air begins to set in
around this trough.
A striking feature of the hot weather season
is the ‘loo’. These are strong, gusty, hot, dry
winds blowing during the day over the north and
northwestern India. Sometimes they even
continue until late in the evening. Direct exposure
to these winds may even prove to be fatal. Dust
storms are very common during the month of
May in northern India. These storms bring
temporary relief as they lower the temperature
and may bring light rain and cool breeze. This is
also the season for localised thunderstorms,
associated with violent winds, torrential
downpours, often accompanied by hail. In West
Bengal, these storms are known as the ‘Kaal
Baisakhi’ calamity for the month of Baisakh.
Towards the close of the summer season,
pre-monsoon showers are common especially,
in Kerala and Karnataka. They help in the early
ripening of mangoes, and are often referred to
as ‘mango showers’.
Advancing Monsoon (The Rainy Season)
By early June, the low-pressure condition over
the northern plains intensifies. It attracts, the
trade winds of the southern hemisphere. These
south-east trade winds originate over the
warm subtropical areas of the southern oceans.
They cross the equator and blow in a southwesterly
direction entering the Indian peninsula
as the south-west monsoon. As these winds
blow over warm oceans, they bring abundant
moisture to the subcontinent. These winds are
strong and blow at an average velocity of 30
km per hour. With the exception of the extreme
north-west, the monsoon winds cover the
country in about a month.
The inflow of the south-west monsoon into
India brings about a total change in the
weather. Early in the season, the windward
side of the Western Ghats receives very heavy
rainfall, more than 250 cm. The Deccan
Plateau and parts of Madhya Pradesh also
receive some amount of rain in spite of lying
in the rain shadow area. The maximum rainfall
of this season is received in the north-eastern
part of the country. Mawsynram in the
southern ranges of the Khasi Hills receives the
highest average rainfall in the world. Rainfall
in the Ganga valley decreases from the east to
the west. Rajasthan and parts of Gujarat get
scanty rainfall.
Another phenomenon associated with the
monsoon is its tendency to have ‘breaks’ in
rainfall. Thus, it has wet and dry spells. In
other words, the monsoon rains take place
only for a few days at a time. They are
interspersed with rainless intervals. These
breaks in monsoon are related to the
movement of the monsoon trough. For
various reasons, the trough and its axis keep
on moving northward or southward, which
determines the spatial distribution of rainfall.
When the axis of the monsoon trough lies over
the plains, rainfall is good in these parts. On
the other hand, whenever the axis shifts closer
to the Himalayas, there are longer dry spells
in the plains, and widespread rain occur in
the mountainous catchment areas of the
Himalayan rivers. These heavy rain bring in
their wake, devastating floods causing
damage to life and property in the plains. The
frequency and intensity of tropical
depressions too, determine the amount and
duration of monsoon rains. These
depressions form at the head of the Bay of
Bengal and cross over to the mainland. The
depressions follow the axis of the “monsoon
34 CONTEMPORARY INDIA
Figure 4.5 : Retreating Monsoon
CLIMATE 35
Mawsynram, the wettest
place on the earth is also reputed for its
stalagmite and stalactite caves.
trough of low pressure”. The monsoon is
known for its uncertainties. The alternation
of dry and wet spells vary in intensity,
frequency and duration. While it causes
heavy floods one part, it may be responsible
for droughts in the other. It is often irregular
in its arrival and its retreat. Hence, it
sometimes disturbs the farming schedule of
millions of farmers all over the country.
Retreating Monsoon
(The Transition Season)
During October-November, with the apparent
movement of the sun towards the south, the
monsoon trough or the low-pressure trough
over the northern plains becomes weaker. This
is gradually replaced by a high-pressure
system. The south-west monsoon winds
weaken and start withdrawing gradually. By
the beginning of October, the monsoon
withdraws from the Northern Plains.
The months of October-November form a
period of transition from hot rainy season to
dry winter conditions. The retreat of the
monsoon is marked by clear skies and rise in
deltas of the Godavari, the Krishna and the
Kaveri are frequently struck by cyclones, which
cause great damage to life and property.
Sometimes, these cyclones arrive at the coasts
of Orissa, West Bengal and Bangladesh. The
bulk of the rainfall of the Coromandel Coast is
derived from depressions and cyclones.
DISTRIBUTION OF RAINFALL
The western coast and northeastern India
receive over about 400 cm of rainfall annualy.
However, it is less than 60 cm in western
Rajasthan and adjoining parts of Gujarat,
Haryana and Punjab. Rainfall is equally low
in the interior of the Deccan plateau, and east
of the Sahyadris. Why do these regions receive
low rainfall? A third area of low precipitation
is around Leh in Jammu and Kashmir. The rest
of the country receives moderate rainfall.
Snowfall is restricted to the Himalayan region.
Owing to the nature of monsoons, the
annual rainfall is highly variable from year to
year. Variability is high in the regions of low
rainfall such as parts of Rajasthan, Gujarat and
the leeward side of the Western Ghats. As such,
while areas of high rainfall are liable to be
affected by floods, areas of low rainfall are
drought-prone (Figure 4.6 and 4.7).
MONSOON AS A UNIFYING BOND
You have already known the way the
Himalayas protect the subcontinent from
extremely cold winds from central Asia. This
enables northern India to have uniformly
higher temperatures when compared to other
areas on the same latitudes. Similarly, the
peninsular plateau, under the influence of the
sea from three sides, has moderate
temperatures. Despite such moderating
influences, there are great variations in the
temperature conditions. Nevertheless, the
unifying influence of the monsoon on the
Indian subcontinent is quite perceptible. The
seasonal alteration of the wind systems and
the associated weather conditions provide a
rhythmic cycle of seasons. Even the
uncertainties of rain and uneven distribution
temperature. While day temperatures are
high, nights are cool and pleasant. The land
is still moist. Owing to the conditions of high
temperature and humidity, the weather
becomes rather oppressive during the day.
This is commonly known as ‘October heat’. In
the second half of October, the mercury begins
to fall rapidly in northern India.
The low-pressure conditions, over northwestern
India, get transferred to the Bay of
Bengal by early November. This shift is
associated with the occurrence of cyclonic
depressions, which originate over the
Andaman Sea. These cyclones generally cross
the eastern coasts of India cause heavy and
widespread rain. These tropical cyclones are
often very destructive. The thickly populated
36 CONTEMPORARY INDIA
Figure 4.6 : Seasonal Rainfall (June-September)
CLIMATE 37
Figure 4.7 : Annual Rainfall
38 CONTEMPORARY INDIA
Activity
(i) On the basis of the news items above, find out the names of places and the seasons described.
(ii) Now answer the following:
(a) Why western winds are associated with winter in the northern region (Delhi, Srinagar, Amritsar & Shimla)
(b) Compare the rainfall description of Chennai and Mumbai and explain the reasons for the difference
CLIMATE 39
are very much typical of the monsoons. The
Indian landscape, its animal and plant life,
its entire agricultural calendar and the life of
the people, including their festivities, revolve
around this phenomenon. Year after year,
people of India from north to south and from
1. Choose the correct answer from the four alternatives given below.
(i) Which one of the following places receives the highest rainfall in the world?
(a) Silchar (c) Cherrapunji
(b) Mawsynram (d) Guwahati
(ii) The wind blowing in the northern plains in summers is known as:
(a) Kaal Baisakhi (c) Trade Winds
(b) Loo (d) None of the above
(iii) Which one of the following causes rainfall during winters in north-western
part of India.
(a) Cyclonic depression (c) Western disturbances
(b) Retreating monsoon (d) Southwest monsoon
(iv) Monsoon arrives in India approximately in:
(a) Early May (c) Early June
(b) Early July (d) Early August
(v) Which one of the following characterises the cold weather season in India?
(a) Warm days and warm nights
(b) Warm days and cold nights
(c) Cool days and cold nights
(d) Cold days and warm nights
2. Answer the following questions briefly.
(i) What are the controls affecting the climate of India?
(ii) Why does India have a monsoon type of climate?
(iii) Which part of India does experience the highest diurnal range of temperature
and why?
(iv) Which winds account for rainfall along the Malabar coast?
(v) What are Jet streams and how do they affect the climate of India?
(vi) Define monsoons. What do you understand by “break” in monsoon?
(vii) Why is the monsoon considered a unifying bond?
3. Why does the rainfall decrease from the east to the west in Northern India.
4. Give reasons as to why.
(i) Seasonal reversal of wind direction takes place over the Indian
subcontinent?
(ii) The bulk of rainfall in India is concentrated over a few months.
(iii) The Tamil Nadu coast receives winter rainfall.
(iv) The delta region of the eastern coast is frequently struck by cyclones.
(v) Parts of Rajasthan, Gujarat and the leeward side of the Western Ghats are
drought-prone.
east to west, eagerly await the arrival of the
monsoon. These monsoon winds bind the
whole country by providing water to set the
agricultural activities in motion. The river
valleys which carry this water also unite as a
single river valley unit.
EXERCISE
40 CONTEMPORARY INDIA
5. Describe the regional variations in the climatic conditions of India with the help
of suitable examples.
6. Discuss the mechanism of monsoons.
7. Give an account of weather conditions and characteristics of the cold season.
8. Give the characteristics and effects of the monsoon rainfall in India.
MAP SKILLS
On an outline map of India, show the following.
(i) Areas receiving rainfall over 400 cm.
(ii) Areas receiving less than 20 cm of rainfall.
(iii) The direction of the south-west monsoon over India.
PROJECT/ACTIVITY
(i) Find out which songs, dances, festivals and special food preparations are
associated with certain seasons in your region. Do they have some
commonality with other regions of India?
(ii) Collect photographs of typical rural houses, and clothing of people from
different regions of India. Examine whether they reflect any relationship
with the climatic condition and
relief of the area.
FOR DOING IT YOURSELF
1. In Table-I the average mean montly
temperatures and amounts of rainfall of ten
representative stations have been given. It is
for you to study on your own and convert them
into ‘temperature and rainfall’ graphs. A
glance at these visual representations will help
you to grasp instantly the smilarities and
differences between them. One such graph
(Figure 1) is already prepared for you. See if
you can arrive at some broad generalisations
about our diverse climatic conditions. We hope
you are in for a great joy of learning. Do the
following activities.
Figure 1 : Temperature and Rainfall of Delhi
2. Re-arrange the ten stations in two different sequences:
(i) According to their distance from the equator.
(ii) According to their altitude above mean sea-level.
3. (i) Name two rainest stations.
(ii) Name two driest stations.
(iii) Two stations with most euqable climate.
(iv) Two stations with most extreme climate.
(v) Two stations most influenced by the Arabian branch of southwest monsoons.
(vi) Two stations most influenced by the Bay of Bengal branch of south-west monsoons.
(vii) Two stations influenced by both branches of the south-west monsoons
(viii) Two stations influenced by retreating and north-east monsoons.
(ix) Two stations receiving winter showers from the western disturbances.
(x) The two hottest stations in the months of
(a) February (b) April (c) May (d) June
CLIMATE 41
4. Now find out
(i) Why are Tiruvanantapuram and Shillong rainier in June than in July?
(ii) Why is July rainier in Mumbai than in Tiruvanantapuram?
(iii) Why are southwest monsoons less rainy in Chennai?
(iv) Why is Shillong rainier than Kolkata?
(v) Why is Kolkata rainier in July than in June unlike Shillong which is rainier in June than
in July?
(vi) Why does Delhi receive more rain than Jodhpur?
5. Now think why
— Tiruvanantapuram has equable climate?
— Chennai has more rains only after the fury of monsoon is over in most parts of the country?
— Jodhpur has a hot desert type of climate?
— Leh has moderate precipitation almost throughut the year?
— while in Delhi and Jodhpur most of the rain is confined to nearly three months, in
Tiruvanantapuram and Shillong it is almost nine months of the year?
In spite of these facts see carefully if there are strong evidences to conclude that the monsoons
still provide a very strong framework lending overall climatic unity to the whole country.
Stations LatitudeAltitude Jan Feb. Mar. Apr. May. Jun. Jul. Aug. Sep. Otc. Nov. Dec. Annual
(Metres) Rainfall
Temperature (°C) 20.5 22.7 25.2 27.1 26.7 24.2 23.0 23.0 23.1 22.9 18.9 20.2
Bangalore 12°58'N 909
Rainfall (cm) 0.7 0.9 1.1 4.5 10.7 7.1 11.1 13.7 16.4 15.3 6.1 1.3 88.9
Temperature (°C) 24.4 24.4 26.7 28.3 30.0 28.9 27.2 27.2 27.2 27.8 27.2 25.0
Mumbai 19° N 11
Rainfall (cm) 0.2 0.2 – – 1.8 50.6 61.0 36.9 26.9 4.8 1.0 – 183.4
Temperature (°C) 19.6 22.0 27.1 30.1 30.4 29.9 28.9 28.7 28.9 27.6 23.4 19.7
Kolkata 22°34' N 6
Rainfall (cm) 1.2 2.8 3.4 5.1 13.4 29.0 33.1 33.4 25.3 12.7 2.7 0.4 162.5
Temperature (°C) 14.4 16.7 23.3 30.0 33.3 33.3 30.0 29.4 28.9 25.6 19.4 15.6
Delhi 29° N 219
Rainfall (cm) 2.5 1.5 1.3 1.0 1.8 7.4 19.3 17.8 11.9 1.3 0.2 1.0 67.0
Temperature (°C) 16.8 19.2 26.6 29.8 33.3 33.9 31.3 29.0 20.1 27.0 20.1 14.9
Jodhpur 26°18' N 224
Rainfall (cm) 0.5 0.6 0.3 0.3 1.0 3.1 10.8 13.1 5.7 0.8 0.2 0.2 36.6
Temperature (°C) 24.5 25.7 27.7 30.4 33.0 32.5 31.0 30.2 29.8 28.0 25.9 24.7
Chennai 13°4' N 7
Rainfall (cm) 4.6 1.3 1.3 1.8 3.8 4.5 8.7 11.3 11.9 30.6 35.0 13.9 128.6
Temperature (°C) 21.5 23.9 28.3 32.7 35.5 32.0 27.7 27.3 27.9 26.7 23.1 20.7
Nagpur 21°9' N 312
Rainfall (cm) 1.1 2.3 1.7 1.6 2.1 22.2 37.6 28.6 18.5 5.5 2.0 1.0 124.2
Temperature (°C) 9.8 11.3 15.9 18.5 19.2 20.5 21.1 20.9 20.0 17.2 13.3 10.4
Shillong 24°34' N 1461
Rainfall (cm) 1.4 2.9 5.6 14.6 29.5 47.6 35.9 34.3 30.2 18.8 3.8 0.6 225.3
Temperature (°C) 26.7 27.3 28.3 28.7 28.6 26.6 26.2 2.6.2 26.5 26.7 26.6 26.5
Tiruvanatapuram 8°29' N 61
Rainfall (cm) 2.3 2.1 3.7 10.6 20.8 35.6 22.3 14.6 13.8 27.3 20.6 7.5 181.2
Temperature (°C) – 8.5 – 7.2 – 0.6 6.1 10.0 14.4 17.2 16.1 12.2 6.1 0.0 – 5.6
Leh 34° N 34°N 3506
Rainfall (cm) 1.0 0.8 0.8 0.5 0.5 0.5 1.3 1.3 0.8 0.5 – 0.5 8.5
Table I


Have you observed the type of trees,
bushes, grasses and birds in the fields
and parks in and around your school?
Are they similar or there are variations? India
being a vast country you can imagine the
types of bio-forms available through out the
country.
Our country India is one of the twelve
mega bio-diversity countries of the world.
With about 47,000 plant species India
occupies tenth place in the world and fourth
in Asia in plant diversity. There are about
15,000 flowering plants in India which
account for 6 per cent in the world’s total
number of flowering plants. The country has
many non-flowering plants such as ferns,
algae and fungi. India also has 89,000 species
of animals as well as a rich variety of fish in
its fresh and marine waters.
Natural vegetation refers to a plant
community which has grown naturally without
human aid and has been left undisturbed by
humans for a long time. This is termed as a
virgin vegetation. Thus, cultivated crops and
fruits, orchards form part of vegetation but not
natural vegetation.
The virgin vegetation, which
are purely Indian are known as endemic or
indigenous species but those which have come
from outside India are termed as exotic plants.
The term flora is used to denote plants of
a particular region or period. Similarly, the
species of animals are referred to as fauna. This
huge diversity in flora and fauna kingdom is
due to the following factors.
NATURAL VEGETATION AND WILD LIFE
RELIEF
Land
Land affects the natural vegetation directly
and indirectly. Do you expect the same type
of vegetation in mountainous, plateau and
plain areas or in dry and wet regions? The
nature of land influences the type of
vegetation. The fertile level is generally devoted
to agriculture. The undulating and rough
terrains are areas where grassland and
woodlands develop and give shelter to a
variety of wild life.
Soil
The soils also vary over space. Different types
of soils provide basis for different types of
vegetation. The sandy soils of the desert
support cactus and thorny bushes while wet,
marshy, deltaic soils support mangroves and
deltaic vegetation. The hill slopes with some
depth of soil have conical trees.
CLIMATE
Temperature
The character and extent of vegetation are
mainly determined by temperature along with
humidity in the air, precipitation and soil. On
the slopes of the Himalayas and the hills of the
Peninsula above the height of 915 metres, the
fall in the temperature affects the types of
vegetation and its growth, and changes it from
tropical to subtropical temperate and alpine
vegetation.
5
NATURAL VEGETATION AND WILD LIFE 43
Photoperiod (Sunlight )
The variation in duration of sunlight at different
places is due to differences in latitude, altitude,
season and duration of the day. Due to longer
duration of sunlight, trees grow faster in
summer.
Why are the southern slopes in Himalayan
region covered with thick vegetation cover as compared
to northern slopes of the same hills?
Precipitation
In India almost the entire rainfall is brought in
by the advancing southwest monsoon (June to
September) and retreating northeast monsoons.
Areas of heavy rainfall have more dense vegetation
as compared to other areas of less rainfall.
Why have the western stopes of the
western ghats covered with thick forests and not
the eastern slopes?
Have you ever thought as to why forests
are important for human beings? Forests are
renewable resources and play a major role in
enhancing the quality of environment. They
modify local climate, control soil erosion,
regulate stream flow, support a variety of
industries, provide livelihood for many
communities and offer panoramic or scenic
view for recreation. It controls wind force and
temperature and causes rainfall. It provides
humus to the soil and shelter to the wild life.
India’s natural vegetation has undergone
many changes due to several factors such as
the growing demand for cultivated land,
development of industries and mining,
urbanisation and over-grazing of pastures.
Activity
Celebrate Van Mahotsav in your school/locality
and plant few spalings and notice their growth
The vegetation cover of India in large parts
is no more natural in the real sense. Except in
some inaccessible regions like the Himalayas,
the hilly region of central India and the
marusthali, the vegetation of most of the areas
has been modified at some places, or replaced
or degraded by human occupancy.
Activity
Study the bar graph (Figure 5.1) and
answer the following questions.
(i) Name the state having maximum area under
forest cover.
(ii) Name the union territory having minimum
area under forest cover and why?
In 2001, the actual forest
cover in India was only 20.55 per cent.
ECOSYSTEM
Plants occur in distinct groups of communities
in areas having similar climatic conditions. The
nature of the plants in an area, to a large extent,
determines the animal life in that area. When
the vegetation is altered, the animal life also
changes. All the plants and animals in an area
are interdependent and interrelated to each
other in their physical environment, thus,
Source : Environment Atlas of India, June 2001, Central Pollution Control Board Delhi
Table 5.1 : Temperature Characteristics of the Vegetation Zones
Vegetation Zones Mean annual Mean Temp. Remarks
Average Temp. inJan. in
(in degree C) degrees C
Tropical Above 24°C Above 18° No Frost
Sub-tropical 17°C to 24°C 10°C to 18°C Frost is rare
Temperate 7°C to 17° C -1°C to (-10 ) °C Frost some snow
Alpine Below 7°C Below–1°C Snow
44 CONTEMPORARY INDIA
forming an ecosystem. Human beings are
also an integral part of the ecosystem. How
do the human beings influence the ecology
of a region? They utilise the vegetation and
wild life. The greed of human beings leads to
over utilisation of these resources. They cut
the trees and kill the animals creating
ecological imbalance. As a result some of the
plants and animals have reached the verge
of extinction.
Do you know that a very large ecosystem
on land having distinct types of vegetation and
animal life is called a biome. The biomes are
identified on the basis of plants.
TYPES OF VEGETATION
The following major types of vegetation may
be identified in our country (Figure 5.3).
(i) Tropical Rain Forests
(ii) Tropical Deciduous Forests
(iii) Tropical Thorn Forests and Scrubs
(iv) Montane Forests
(v) Mangrove Forests
Tropical Rain Forests
These forests are restricted to heavy rainfall
Figure 5.1 Area Under Forest Cover
areas of the Western Ghats and the island
groups of Lakshadweep, Andaman and Nicobar,
upper parts of Assam and Tamil Nadu coast.
100
80
60
40
20
0
ANDHRA PRADESH
ARUNACHAL PRADESH
ASSAM
BIHAR & JHARKHAND
GOA
GUJARAT
HARYANA
HIMACHAL PRADESH
JAMMU AND KASHMIR
KARNATAKA
KERALA
MADHYA PRADESH & CHHATISGARH
MAHARASHTRA
MANIPUR
MEGHALAYA
MIZORAM
NAGALAND
ORISSA
PUNJAB
RAJASTHAN
SIKKIM
TAMILNADU
TRIPURA
UTTAR PRADESH & UTTARANCHAL
WEST BENGAL
A & N ISLANDS
CHANDIGARH
DADRA & NAGARHAVELI
DAMAN & DIU
DELHI
LAKHSHADWEEP
PONDICHERRY
Source : Environment Atlas of India, June 2001, Central Pollution Control Board Delhi
AREA IN PERCENT
ACTUAL FOREST AREA
Figure 5.2 : Tropical Rain Forest
NATURAL VEGETATION AND WILD LIFE 45
Study the given map for the forest cover and try to find the reasons as to why certain states have more area under
forest as compared to others?
Figure 5.3 : Natural Vegetation
46 CONTEMPORARY INDIA
Figure 5.4 : Tropical Deciduous Forest
In these forests, the common animals found
are lion, tiger, pig, deer and elephant. A huge
variety of birds, lizards, snakes, and tortoises
are also found here.
The Thorn Forests and Scrubs
In regions with less than 70 cm of rainfall,
the natural vegetation consists of thorny trees
and bushes. This type of vegetation is found
in the north-western part of the country
including semi-arid areas of Gujarat,
Rajasthan, Madhya Pradesh, Chhattisgarh,
Uttar Pradesh and Haryana. Acacias, palms,
euphorbias and cacti are the main plant
species. Trees are scattered and have long roots
penetrating deep into the soil in order to get
moisture. The stems are succulent to conserve
water. Leaves are mostly thick and small to
minimize evaporation. These forests give way
to thorn forests and scrubs in arid areas.
Figure 5.5 : Thorn Forests and Scrubs
They are at their best in areas having more than
200 cm of rainfall with a short dry season. The
trees reach great heights up to 60 metres or even
above. Since the region is warm and wet
throughout the year, it has a luxuriant
vegetation of all kinds – trees, shrubs, and
creepers giving it a multilayered structure. There
is no definite time for trees to shed their leaves.
As such, these forests appear green all the year
round.
Some of the commercially important trees
of this forest are ebony, mahogany, rosewood,
rubber and cinchona.
The common animals found in these forests
are elephants, monkey, lemur and deer. The
one horned rhinoceros are found in the jungles
of Assam and West Bengal. Besides these
animals plenty of birds, bats, sloth, scorpions
and snails are also found in these jungles.
Tropical Deciduous Forests
These are the most widespread forests of India.
They are also called the monsoon forests and
spread over the region receiving rainfall
between 200 cm and 70 cm. Trees of this
forest-type shed their leaves for about six to
eight weeks in dry summer.
On the basis of the availability of water,
these forests are further divided into moist and
dry deciduous. The former is found in areas
receiving rainfall between 200 and 100 cm.
These forests exist, therefore, mostly in the
eastern part of the country – northeastern
states, along the foothills of the Himalayas,
Jharkhand, West Orissa and Chhattisgarh, and
on the eastern slopes of the Western Ghats.
Teak is the most dominant species of this forest.
Bamboos, sal, shisham, sandalwood, khair,
kusum, arjun, mulberry are other commercially
important species.
The dry deciduous forests are found in areas
having rainfall between 100 cm and 70 cm.
These forests are found in the rainier parts of
the peninsular plateau and the plains of Bihar
and Uttar Pradesh. There are open stretches
in which Teak, Sal, Peepal, Neem grow. A large
part of this region has been cleared for
cultivation and some parts are used for grazing.
NATURAL VEGETATION AND WILD LIFE 47
Figure 5.7 : Mangrove Forests
In these forests, the common animals are
rats, mice, rabbits, fox, wolf, tiger, lion, wild
ass, horses and camels.
Montane Forests
In mountainous areas, the decrease in
temperature with increasing altitude leads to
the corresponding change in natural
vegetation. As such, there is a succession of
natural vegetation belts in the same order as
we see from the tropical to the tundra region.
The wet temperate type of forests are found
between a height of 1000 and 2000 metres.
Evergreen broad-leaf trees such as oaks and
chestnuts predominate. Between 1500 and
3000 metres, temperate forests containing
coniferous trees like pine, deodar, silver fir,
spruce and cedar, are found. These forests
cover mostly the southern slopes of the
Himalayas, places having high altitude in
southern and north-east India. At higher
elevations, temperate grasslands are common.
At high altitudes, generally more than 3,600
metres above sea-level, temperate forests and
grasslands give way to the Alpine vegetation.
Silver fir, junipers, pines and birches are the
common trees of these forests. However, they
get progressively stunted as they approach
the snow-line. Ultimately through shrubs and
scrubs, they merge into the Alpine
grasslands. These are used extensively for
grazing by nomadic tribes like the Gujjars
and the Bakarwals. At higher altitudes,
mosses and lichens form part of tundra
vegetation.
The common animals found in these forests
are Kashmir stag, spotted dear, wild sheep, jack
rabbit, Tibetan antelope, yak, snow leopard,
squirrels, Shaggy horn wild ibex, bear and rare
red panda, sheep and goats with thick hair.
Mangrove Forests
The mangrove tidal forests are found in the
areas of coasts influenced by tides. Mud and
silt get accumutated on such coasts. Dense
mangroves are the common varieties with roots
of the plants submerged under water. The
deltas of the Ganga, the Mahanadi, the
Krishana, the Godavari and the Kaveri are
covered by such vegetation. In the Ganga-
Brahamaputra delta, sundari trees are
found, which provide durable hard timber.
Palm, coconut, keora, agar, also grow in
some parts of the delta.
Royal Bengal Tiger is the famous animal
in these forests. Turtles, crocodiles, gharials
and snakes are also found in these forests.
Let us discuss : What will happen if plants and
animals disappear from the earth’s surface? can
the human beings survive under such a situation?
Why is bio-diversity necessary and why should it
be conserved?
Figure 5.6 : Montane Forests
48 CONTEMPORARY INDIA
MEDICINAL PLANTS
India is known for its herbs and spices from ancient times. Some 2,000 plants have been described in Ayurveda
and atleast 500 are in regular use. The World Conservation Union’s Red list has named 352 medicinal plants of
which 52 are critically threatened and 49 endangered. The commonly used plants in India are:
Sarpagandha : Used to treat blood pressure; it is found only in India.
Jamun : The juice from ripe fruit is used to prepare vinegar which is carminative and diuretic, and
has digestive properties. The powder of the seed is used for controlling diabetes.
Arjun : The fresh juice of leaves is a cure for earache. It is also used to regulate blood pressure.
Babool : Leaves are used as a cure for eye sores. Its gum is used as a tonic.
Neem : Has high antibiotic and antibacterial properties.
Tulsi Plant : Is used to cure cough and cold.
Kachnar : Is used to cure asthma and ulcers. The buds and roots are good for digestive problems.
Identify more medicinal plants in your area. Which plants are used as medicines by local
people to cure some diseases?
WILD LIFE
Like its flora, India is also rich in its fauna. It
has more than 89,000 of animal species. The
country has more than 1200 species of birds.
They constitute 13% of the world’s total. There
are 2500 species of fish, which account for
nearly 12% of the world’s stock. It also shares
between 5 and 8 per cent of the world’s
amphibians, reptiles and mammals.
The elephants are the most majestic
animals among the mammals. They are found
in the hot wet forests of Assam, Karnataka and
Kerala. One-horned rhinoceroses are the other
animals, which live in swampy and marshy
lands of Assam and West Bengal. Arid areas
of the Rann of Kachchh and the Thar Desert
are the habitat for wild ass and camels
respectively. Indian bison, nilgai (blue bull),
chousingha (four horned antelope), gazel and
different species of deer are some
other animals found in India. It also
has several species of monkeys.
Wildlife Protection
Act, was implemented in 1972 in India.
India is the only country in the
world that has both tigers and lions.
The natural habitat of the Indian lion
is the Gir forest in Gujarat. Tigers are
found in the forests of Madhya Pradesh,
the Sundarbans of West Bengal and the
Himalayan region. Leopards too are
members of the cat family. They are
important among animals of prey.
The Himalayas harbour a hardy range of
animals, which survive in extreme cold.
Ladhak’s freezing high altitudes are a home to
yak, the shaggy horned wild ox weighing
around one tonne, the Tibetan antelope, the
bharal (blue sheep), wild sheep, and the kiang
(Tibetan wild ass). Furhtermore, the ibex, bear,
snow-leopard and very rare red panda are
found in certain pockets.
In the rivers, lakes and coastal areas,
turtles, crocodiles and gharials are found. The
Source : Medicinal Plants by Dr. S.K. Jain, 5th edition 1994, National Book Trust of Inida
Activity
Can you identify the type of forest shown in this
picture? Identify some trees in it. What type of
similarity/dissimilarity you notice in this type
of vegetation from the one found in your region?
Do you know
The Gir Forest is the
last remaining habitat
of the Asiatic lion.
NATURAL VEGETATION AND WILD LIFE 49
Figure 5.8 : Wildlife Reserves
50 CONTEMPORARY INDIA
latter is the only representative of a variety of
crocodile, found in the world today.
Bird life in India is colourful. Peacocks,
peasants, ducks, parakeets, cranes and
pigeons are some of the birds inhabiting the
forests and wetlands of the country.
We have selected our crops from a biodiverse
environment i.e. from the reserve of
edible plants. We also experimented and
selected many medicinal plants. The animals
were selected from large stock provided by
nature as milch animal. They also provided
us draught power, transportation, meat,
eggs. The fish provide nutritive food. Many
insects help in pollination of crops and fruit
trees and exert biological control on such
insects, which are harmful. Every species has
a role to play in the ecosystem. Hence,
conservation is essential. As has been
mentioned earlier due to excessive
exploitation of the plants and animal
resources by human beings, the ecosystem
has been disturbed. About 1,300 plant
species are endangered and 20 species are
extinct. Quite a few animal species are also
endangered and some have become extinct.
The main causes for this major threat to
nature are hunting by greedy hunters for
commercial purposes. Pollution due to
chemical and industrial waste, acid deposits,
introduction of alien species and reckless
cutting of the forests to bring land under
cultivation and inhabitation, are also
responsible for the imbalance.
To protect the flora and fauna of the
county, the government has taken many steps.
(i) Fourteen biosphere reserves have been set
up in the country to protect flora and fauna.
Four out of these, the Sunderbans in the
West Bengal, Nanda Devi in Uttaranchal,
the Gulf of Mannar in Tamil Nadu and the
Nilgiris (Kerala, Karnataka and Tamil
Nadu) have been included in the world
network of Biosphese reserves.
Activity
(i) Find out from the above newspaper cuttings, the main concern highlighted in the given news items.
(ii) Collect more information about various endangered species from newspapers and magazines.
(iii) Find out various steps taken by the Indian government to protect them.
(iv) Discribe how you can contribute to the protection of endangered animals and birds?
NATURAL VEGETATION AND WILD LIFE 51
1. Choose the right answer from the four alternatives given below:
(i) To which one of the following types of vegetation does rubber belong to?
(a) Tundra (c) Himalayan
(b) Tidal (d) Tropical Evergreen
(ii) Cinchona trees are found in the areas of rainfall more than
(a) 100 cm (c) 70 cm
(b) 50 cm (d) less than 50 cm
(iii) In which of the following state is the Simlipal bio-reserve located?
(a) Punjab (b) Delhi
(c) Orissa (d) West Bengal
(iv) Which one of the following bio-reserves of India is not included in the world
network of bioreserve?
(a) Manas (c) Gulf of Mannar
(b) Dihang-Dibang (d) Nanda devi
Fourteen Bio-reserves
• Sunderbans • Simlipal
• Gulf of Mannar • Dihang-Dibang
• The Nilgiris • Dibru Saikhowa
• Nanda Devi • Agasthyamalai
• Nokrek • Kanchenjunga
• Great Nicobar • Pachmari
• Manas • Achanakmar-Amarkantak
(ii) Financial and technical assistance is
provided to many Botanical Gardens by the
government since 1992.
Migratory Birds
Some of the wetlands of India are popular
with migratory birds. During winter,
birds, such as Siberian Crane come in
large numbers. One such place
favourable with birds is the Rann of
Kachchh. At a place where the desert
merges with the sea, flamingo with their
brilliant, pink plumage, come in
thousands to build nest mounds from the
salty mud and raise their young ones. It
is one among many extraordinary sights
in the country. Is it not a rich natural
heritage of ours?
(iii) Project Tiger, Project Rhino, Project Great
Indian Bustard and many other ecodevelopmental
projects have been
introduced.
(iv) 89 National Parks, 49 Wildlife sanctuaries
and Zoological gardens are set up to take
care of Natural heritage.
All of us must realise the importance of the
natural ecosystem for our own survival. It
is possible if indiscriminate destruction of
natural environment is put to an
immediate end.
EXERCISE
52 CONTEMPORARY INDIA
2. Answer the following questions briefly.
(i) Define an ecosystem.
(ii) What factors are responsible for the distribution of plants and animals in
India?
(iii) What is a bio-reserve? Give two examples.
(iv) Name two animals having habitat in tropical and montane type of vegetation.
3. Distinguish between
(i) Flora and Fauna
(ii) Tropical Evergreen and Deciduous forests
4. Name different types of Vegetation found in India and describe the vegetation of
high altitudes.
5. Quite a few species of plants and animals are endangered in India. Why?
6. Why has India a rich heritage of flora and fauna?
Map Skills
On an outline map of India, label the following.
(i) Areas of Evergreen Forests
(ii) Areas of Dry Deciduous Forests
(iii) Two national parks each in Northern, Southern, Eastern and Western parts
of the Country
Project/Activity
(i) Find some trees in your neighbourhood having medicinal values.
(ii) Find ten occupations getting raw material from forests and wild life.
(iii) Write a poem or paragraph showing the importance of wild life.
(iv) Write the script of a street play giving the importance of tree plantation and
try to enact it in your locality.
(v) Plant a tree either on your birthday or one of your family member’s birthday.
Note the growth of the tree and notice in which season it grows faster.


POPULATION
Can you imagine a world without human
beings? Who would have utilised
resources and created the social and
cultural environment? The people are
important to develop the economy and society.
The people make and use resources and are
themselves resources with varying quality.
Coal is but a piece of rock, until people were
able to invent technology to obtain it and make
it a ‘resource’. Natural events like a river flood
or Tsunami becomes a ‘disaster’ only when
they affect a crowded village or a town.
Hence, population is the pivotal element in
social studies. It is the point of reference from
which all other elements are observed and from
which they derive significance and meaning.
‘Resources’, ‘calamities’ and ‘disasters’ are all
meaningful only in relation to human beings.
Their numbers, distribution, growth and
characteristics or qualities provide the basic
background for understanding and
appreciating all aspects of the environment.
Human beings are producers and
consumers of earth’s resources. Therefore, it
is important to know how many people are
there in a country, where do they live, how and
why their numbers are increasing and what
are their characteristics. The census of India
provides us with information regarding the
population of our country.
We are primarily concerned with three
major questions about the population:
(i) Population size and distribution: How
many people are there and where are they
located?
(ii) Population growth and processes of
population change: How has the
population grown and changed through
time?
(iii) Characteristics or qualities of the
population: What are their age, sexcomposition,
literacy levels, occupational
structure and health conditions?
POPULATION SIZE AND DISTRIBUTION
India’s Population Size and Distribution by
Numbers
India’s population as on March 2001 stood at
1,028 million, which account for 16.7 per cent
of the world’s population. These 1.02 billion
people are unevenly distributed over our
country’s vast area of 3.28 million square km,
which accounts for 2.4 per cent of the world’s
area (Figure 6.1)
The 2001 Census data reveals that Uttar
Pradesh with a population size of 166 million
people is the most populous state of India. Uttar
Pradesh accounts for about 16 per cent of the
Census
A census is an official enumeration of population done periodically. In India the first census was held in the year
1872. The first complete census, however was taken in the year 1881. Since then censuses have been held
regularly every tenth year.
The Indian Census is the most comprehensive source of demographic, social and economic data. Have you
ever seen a census report? Check in your library if it has one.
6
54 CONTEMPORARY INDIA
Do You Know? Only Bangladesh and Japan have
higher average population densities
than India. Find out the population densities of
Bangladesh and Japan.
is calculated as the number of persons per unit
area. India is one of the most densely populated
countries of the world.
The population density of India in the year
2001 was 324 persons per sq km. Densities
vary from 904 persons per sq km in West
Bengal to only 13 persons per sq km in
Arunachal Pradesh. A study of the figure 6.3
shows the pattern of uneven distribution of
population densities at the state level.
Activity
Study the figure 6.3 and compare it with
figure 2.4 and figure 4.7. Do you find any
corelation between these maps?
Note the states with population densities
below 250 persons per square km. Rugged
terrain and unfavourable climatic conditions
are primarily responsible for sparse population
in these areas. Which states have density below
100 persons per square km?
Assam and most of the Peninsular states
have moderate population densities. Hilly,
dissected and rocky nature of the terrain,
moderate to low rainfall, shallow and less
fertile soils have influenced population
densities in these areas.
The Northern Plains and Kerala in the
south have high to very high population
densities because of the flat plains with fertile
soils and abundant rainfall. Identify the three
states of the Northern Plains with high
population densities.
POPULATION GROWTH AND PROCESSES OF
POPULATION CHANGE
Population is a dynamic phenomenon. The
numbers, distribution and composition of the
population are constantly changing. This is the
influence of the interaction of the three processes,
namely-births, deaths and migrations.
India, 16.7%
Rest of the world, 83.3%
Rest of the world, 97.6%
India, 2.4%
AREA
POPULATION
Fig 6.1 : India’s share of world’s area and population
Others 51.2%
Uttar
Pradesh 16.16%
Maharashtra
9.42%
Bihar
8.02%
W. Bengal
7.79%
Andhra
Pradesh 7.41%
country’s population. On the other hand, the
Himalayan state Sikkim has a population of
just about 0.5 million and Lakshadweep has
only 60 thousand people.
Almost half of India’s population lives in
just five states. These are Uttar Pradesh,
Maharashtra, Bihar, West Bengal, and Andhra
Pradesh. Rajasthan, the biggest state in terms
of area, has only 5.5 per cent of the total
population of India (Figure 6.2)
• What could be the reason of uneven
distribution of population in India?
India’s Population Distribution by Density
Population density provides a better picture
of the uneven distribution. Population density
Figure 6.2 : Distribution of Population
POPULATION 55
Figure 6.3 : Density of Population in India
HARYANA
56 CONTEMPORARY INDIA
12
10
8
6
4
2
0
1951 1961 1971 1981 1991 2001
2.5
2
1.5
1
0.5
0
Year
Population in Millions
Total Pupulation
Annual Growth
Annual Growth Rate %
Table 6.1 and figure 6.4 reveal that from
1951 to 1981, the annual rate of population
growth was steadily increasing; which
explains the rapid increase in population
from 361 million in 1951 to 683 million in
1981.
• Table 6.1 reveals that despite the
decline in growth rates, the number of people being
added every decade is steadily increasing. Why?
Since 1981, however, the rate of growth
started declining gradually. During this
period, birth rates declined rapidly. Still 182
million people were added to the total
population in the 1990s alone (an annual
addition larger than ever before).
It is essential to realise that India has a very
large population. When a low annual rate is
applied to a very large population, it yields a
large absolute increase. When more than a
billion people increase even at a lower rate, the
total numbers being added becomes very large.
India’s current annual increase in population
of 15.5 million is large enough to neutralise
efforts to conserve the resource endowment
and environment.
The declining trend of the growth rate is
indeed a positive indicator of the efforts of birth
control. Despite that, the total additions to the
population base continue to grow, and India
may overtake China in 2045 to become the
most populous country in the world.
Population Growth
Growth of population refers to the change in
the number of inhabitants of a country/territory
during a specific period of time, say during the
last ten years. Such a change can be expressed
in two ways: in terms of absolute numbers and
in terms of percentage change per year.
The absolute numbers added each year or
decade is the magnitude of increase. It is
obtained by simply subtracting the earlier
population (e.g. that of 1991) from the later
population (e.g. that of 2001). It is referred to
as the absolute increase.
The rate or the pace of population increase
is the other important aspect. It is studied in
per cent per annum, e.g. a rate of increase of 2
per cent per annum means that in a given year,
there was an increase of two persons for every
100 persons in the base population. This is
referred to as the annual growth rate.
India’s population has been steadily
increasing from 361 million in 1951 to 1028
million in 2001.
Table 6.1 : The Magnitude and Rate of India’s
Population Growth
Year Total Absolute Annual
Population Increase in Growth
(in millions) the decade Rate
(in million) ( % )
1951 361.0 42.43 1.25
1961 439.2 78.15 1.96
1971 548.2 108.92 2.20
1981 683.3 135.17 2.22
1991 846.4 163.09 2.14
2001 1028.7 182.32 1.93
Figure 6.4 : India’s Population and Population Growth Rates during 1951-2001
POPULATION 57
Processes of Population Change/Growth
There are three main processes of change of
population : birth rates, death rates and
migration.
The natural increase of population is the
difference between birth rates and death rates.
Birth rate is the number of live births per
thousand persons in a year. It is a major
component of growth because in India, birth
rates have always been higher than death
rates.
Death rate is the number of deaths per
thousand persons in a year. The main cause
of the rate of growth of the Indian population
has been the rapid decline in death rates.
Till 1980, high birth rates and declining
death rates led to a large difference between
birth rates and death rates resulting in higher
rates of population growth. Since 1981, birth
rates have also started declining gradually,
resulting in a gradual decline in the rate of
population growth. What are the reasons for
this trend?
The third component of population growth
is migration. Migration is the movement of
people across regions and territories. Migration
can be internal (within the country) or
international (between the countries).
Internal migration does not change the size
of the population, but influences the distribution
of population within the nation. Migration plays
a very significant role in changing the composition
and distribution of population.
Activity
On a map, trace the migration of each
of your grandparents and parents
since their birth. Try and analyse the
reasons for each move.
In India, most migrations have been from
rural to urban areas because of the “push”
factor in rural areas. These are adverse
conditions of poverty and unemployment in the
rural areas and the “pull” of the city in terms
of increased employment opportunities and
better living conditions.
Migration is an important determinant of
population change. It changes not only the
population size but also the population
composition of urban and rural populations
in terms of age and sex composition. In India,
the rural-urban migration has resulted in a
steady increase in the percentage of population
in cities and towns. The urban population has
increased from 17.29 per cent of the total
population in 1951 to 27.78 per cent in 2001.
There has been a significant increase in the
number of ‘million plus cities’ from 23 to 35 in
just one decade i.e. 1991 to 2001.
Age Composition
The age composition of a population refers to
the number of people in different age groups
in a country. It is one of the most basic
characteristics of a population. To an important
degree, a person’s age influences what he
needs, buys, does and his capacity to perform.
Consequently, the number and percentage of
a population found within the children,
working age and aged groups are notable
determinants of the population’s social and
economic structure.
The population of a nation is generally
grouped into three broad categories:
Children (generally below 15 years)
They are economically unproductive and need
to be provided with food, clothing, education
and medical care.
Figure 6.5: India: Age Composition
Adults, 58.7%
Aged, 6.9%
Children, 34.4%
India : Age Structure
58 CONTEMPORARY INDIA
Working Age (15-59 years)
They are economically productive and
biologically reproductive. They comprise the
working population.
Aged (Above 59 years)
They can be economically productive though
they and may have retired. They may be
working voluntarily but they are not available
for employment through recruitment.
The percentage of children and the aged
affect the dependency ratio because these
groups are not producers. The proportion of
the three groups in India’s population is
already presented in figure 6.5 .
Activity :
(i) How many children do you know who are
engaged as household helpers, labourers in
your locality?
(ii) How many adults do you know in your locality
who are unemployed?
(iii) What do you feel are the reasons for this?
Sex Ratio
Sex ratio is defined as the number of females
per 1000 males in the population. This
information is an important social indicator
to measure the extent of equality between
males and females in a society at a given time.
The sex ratio in the country has always
remained unfavourable to females. Find out
why this is so? Table 6.2 shows the sex ratio
from 1951-2001.
Table 6.2 : India : Sex Ratio 1951-2001
Census year Sex ratio
(Females per 1000 males)
1951 946
1961 941
1971 930
1981 934
1991 929
2001 933
• Kerala has a sex ratio of 1058
females per 1000 males, Pondicherry has 1001
females for every 1000males, while Delhi has
only 821 females per 1000 and Haryana has
just 861.
• What could be the reasons for such
variations?
Literacy Rates
Literacy is a very important quality of a
population. Obviously, only an informed and
educated citizen can make intelligent choices
and undertake research and development
projects. Low levels of literacy are a serious
obstacle for economic improvement.
According to the Census of 2001, a person
aged 7 years. and above who can read and
write with understanding in any language, is
treated as literate.
There has been a steady improvement in
the literacy levels in India. The literacy rate in
the country as per the Census of 2001 is 64.84
per cent; 75.26 per cent for males and 53.67
per cent for females. Why do such differences
exist?
Occupational Structure
The percentage of population that is
economically active is an important index of
development. The distribution of the
population according to different types of
occupation is referred to as the occupational
structure. An enormous variety of occupations
are found in any country. Occupations are
generally classified as primary, secondary, and
tertiary.
Primary activities include agriculture,
animal husbandry, forestry, fishing, mining
and quarrying etc. Secondary activities include
manufacturing industry, building and
construction work etc. Tertiary activities
include transport, communications,
commerce, administration and other services.
The proportion of people working in
different activities varies in developed and
developing countries. Developed nations have
a high proportion of people in secondary, and
tertiary activities. Developing countries tend
to have a higher proportion of their workforce
engaged in primary activities. In India, about
64 per cent of the population is engaged only
in agriculture. The proportion of population
dependent on secondary and tertiary sectors
POPULATION 59
is about 13 and 20 per cent respectively. There
has been an occupational shift in favour of
secondary and tertiary sectors because of
growing industrialisation and urbanisation in
recent times.
Health
Health is an important component of
population composition, which affects the
process of development. Sustained efforts of
government programmes have registered
significant improvements in the health
conditions of the Indian population. Death
rates have declined from 25 per 1000
population in 1951 to 8.1 per 1000 in 2001
and life expectancy at birth has increased from
36.7 years in 1951 to 64.6 years in 2001.
The substantial improvement is the result
of many factors including improvement in
public health, prevention of infectious diseases
and application of modern medical practices
in diagnosis and treatment of ailments.
Despite considerable achievements, the
health situation is a matter of major concern
for India. The per capita calorie consumption
is much below the recommended levels and
malnutrition afflicts a large percentage of our
population. Safe drinking water and basic
sanitation amenities are available to only onethird
of the rural population. These problems
need to be tackled through an appropriate
population policy.
Adolescent Population
The most significant feature of the Indian
population is the size of its adolescent
population. It constitutes one-fifth of the total
population of India. Adolescents are generally
grouped in the age-group of 10 to 19 years.
They are the most important resource for the
future. Nutrition requirements of adolescents
are higher than those of a normal child or adult.
Poor nutrition can lead to deficiency and
stunted growth. But in India, the diet available
to adolescents is inadequate in all nutrients. A
large number of adolescent girls suffer from
anaemia. Their problems have so far not
received adequate attention in the process of
development. The adolescent girls have to be
sensitised to the problems they confront. Their
awareness can be improved through the spread
of literacy and education among them.
National Population Policy
Recognising that the planning of families would
improve individual health and welfare, the
Government of India initiated the
comprehensive Family Planning Programme in
1952. The Family Welfare Programme has
sought to promote responsible and planned
parenthood on a voluntary basis. The National
Population Policy 2000 is a culmination of
years of planned efforts.
The NPP 2000 provides a policy framework
for imparting free and compulsory school
education up to 14 years of age, reducing
infant mortality rate to below 30 per 1000 live
births, achieving universal immunisation of
children against all vaccine preventable
diseases, promoting delayed marriage for girls,
and making family welfare a people-centered
programme.
NPP 2000 and Adolescents
NPP 2000 identified adolescents as one of the
major sections of the population that need
greater attention. Besides nutritional
requirements, the policy put greater emphasis
on other important needs of adolescents
including protection from unwanted
pregnancies and sexually transmitted diseases
(STD). It called for programmes that aim
towards encouraging delayed marriage and
child-bearing, education of adolescents about
the risks of unprotected sex, making
contraceptive services accessible and
affordable, providing food supplements,
nutritional services, strengthening legal
measures to prevent child marriage.
People are the nation’s most valuable
resource. A well- educated healthy population
provides potential power.
60 CONTEMPORARY INDIA
1. Choose the right answer from the four alternatives given below.
(i) Migrations change the number, distribution and composition of the
population in
(a) the area of departure (c) both the area of departure and arrival
(b) the area of arrival (d) none of the above
(ii) A large proportion of children in a population is a result of
(a) high birth rates (c) high death rates
(b) high life expectancies (d) more married couples
(iii) The magnitude of population growth refers to
(a) the total population of an area
(b) the number of persons added each year
(c) the rate at which the population increases
(d) the number of females per thousand males
(iv) According to the Census 2001, a “literate” person is one who
(a) can read and write his/her name
(b) can read and write any language
(c) is 7 years old and can read and write any language with understanding
(d) knows the 3 ‘R’s (reading, writing, arithematic)
2. Answer the following questions briefly.
(i) Why is the rate of population growth in India declining since 1981?
(ii) Discuss the major components of population growth.
(iii) Define age structure, death rate and birth rate.
(iv) How is migration a determinant factor of population change?
3. Distinguish between population growth and population change.
4. What is the relation between occupational structure and development?
5. What are the advantages of having a healthy population?
6. What are the significant features of the National Population Policy 2000?
PROJECT/ACTIVITY
Conduct a class census by preparing a questionnaire. The questionnaire should
contain minimum five questions. Questions should relate to students, their
family members, their class performance, their health etc. Each student is
required to fill up the questionnaire. Compile the information in numerical terms
(in terms of percentage). Present the information through pie-chart, bar-diagram
or in any other way.
EXERCISE