O-Level Geography Chapter 2 Climate Factors Affecting Climate

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There are four climatic elements responsible for seasonal variations in

the climate of Pakistan

• Temperature
• Rainfall
• Pressure
• Winds

Factors effecting temperature of Pakistan

1. Angle of Sun and Latitudinal effect

Temperature and rainfall are both dependent either directly or indirectly on the influence of the sun. The sun’s influence varies from place to place due to factors like angle of sun at a particular place.

As it is evident the Polar Regions or regions far away from the Equator are generally cooler than the ones nearer the Equator. This is because for solar radiation to reach the poles and heat them it has to travel a larger distance in space, thus it loses its intensity (energy). Also near the poles the radiation arrives at an oblique angle so solar energy spreads over a large area. Since Pakistan lies in subtropical areas it does receive most of intense solar radiation concentrated on a small area thus the temperature in general is warmer. So in general terms Faisalabad will be cooler than say Hyderabad.

2. Altitude and temperature

The temperature is highly dependent on altitude, air density and temperature. The air is densest at sea level due to water vapour ,dust particles and solar radiation and least dense at high altitude because of less solar radiation is absorbed with less air to absorb heat .there is an average drop of 6.5 C in temperature for each 1000 metre increase in altitude.

3. Cloud cover and Temperature

Temperatures decrease when clouds appear and block out the Sun’s rays, which are then reflected back into space. However cloud formation only takes place when air contains sufficient moisture and has been sufficiently cooled. Thus cloudy days are much cooler than sunny days during the same months.

4. Continental effect:

It refers to all those areas having distance from the sea(interior region) hence does not gets maritime influence of the sea on temperature therefore the temperature is never moderate hence extreme winters and summers are recorded.