CH 4

CLIMATE

Climate is the most important element of environment on the earth after formation of land or solid outer surface of the earth.

1. Elements of climate and weather

a) Temperature( root element)

b) Air pressure

c) Winds

d) Humidity

e) Cloudiness

f) Precipitation/rainfall(fruit element)

2. CLIMATE

It refers to the sum total of weatherconditions over a large area for a longer period of time.(more than 30 years)

3. WEATHER

It refers to the state of atmosphere over an area /place at any point of time. It is temporary picture of atmosphere in terms of elements of weather.

Chain of elements make the climate and weather conditions.

Air always moves from high pressure to low pressure.

Horizontal movement of air is known as winds.

Air also moves vertically. Vertical movement of air is known as air current.

Dry air

No water vapour or very low water vapour.

Poor air humidity in air.

High amount of water vapour raises the humidity level of air.

Cooling of humid air results into condensation and formation of clouds.

Greater the amount of humidity, higher will be the clouds formation.

Thickness and intensity of cloud formation shall lead to precipitation(rainfall).

Forms of precipitation- rainfall(most common and important), drizzle, snowfall, sleet, hail stones.

For rainfall only moisture or humidity is not enough, the moist air is needed to rise up and cooling and to condense.

There are mainly 3 ways to make the moist air to rise up and hence the three types of precipitation-

a) Relief/orographic/mountainous precipitation

b) Convectional precipitation

c) Cyclonic/frontal precipitation

Monsoon type of climate Monsoon refers to the reversal change in the

wind direction during a year. India’s climate is refered as monsoon type of

climate.

Two main factors to control the climate of India-

a) Location in relation to equatorb) Location in related to water bodiesc) Relief/ mountain/ himalyas