Factors Affecting Climate
Climate of a region is never constant. Many factors control the climate and their combined effects result in a particular type of climate at a particular place. Some of these are:
(J)SoIarEnergy
The Sun is the ultimate sourbe of energy for our planet.
At the same time, it is this energy only, which has made the earth habitable. The solar energy received by the earth is responsible for maintaining the temperature suitable for the existence of various life forms. The variation in the amount of solar radiation received is the reason for the existence of different temperature and air pressure zones in different regions of the Earth.(ii) Oceans and Water Bodies
About 75% of the Earth is covered by water bodies such as oceans and seas. The availability of water vapours and precipitation influence the climate by their effect on air temperature.
In addition, ocean currents also redistribute the heat. Ocean currents are the movement of large amounts of warm water from lower to higher latitudes and that of cold water from higher to lower latitude for replacing it. These currents strongly affect the temperature and the humidity of adjacent air mass which affect the climate and weather conditions of adjacent coastal and continental areas along the path of the current.
Water bodies stabilize temperature because they heat and cool more slowly than the land. The variation of air temperature on water bodies is less as compared tb that on land. Also, the coastal areas do not have extreme temperatures as faced by the land masses. The land areas have comparatively hotter summers and colder winters.
(iii) Altitude
The atmosphere gets heated through the earth’s surface. As we go up, the temperature decreases. Moisture laden air cools on moving up and further condensation of water vapours ultimately leads to precipitation.
(iv) Wind Systems
These are land and sea breezes as well as mountain and valley breezes. Land warms up and cools faster than water. Therefore, there is a low pressure over land during daytime. Thus, air flows from sea to land causing the sea breeze. The reverse happens at night causing the land breeze.
Similarly, warm air rises up the mountain slopes and valleys during the daytime whereas in the night, cool air descends down the slope.
In addition to the above natural factors affecting the climate patterns, human activities are changing the climate in a much drastic way and at a much faster rate. These include pollution in general and air pollution, in particular. The harmful effects of air pollution have been dealt in Chapter 4. Air Pollution affects human health, plant and animal life and buildings as well. It also causes the occurrence of smog, ozone depletion and global warming.
Industrialization and developmental activities including urbanization has caused deforestation, loss of soil cover etc. and has replaced vegetation by roads and buildings. Such changes are normally accompanied by the increase in temperature, winds, relative humidity and clouds as well as fog. Also, there is an increase in the amount of gaseous oxides and dust particles in the atmosphere. All these have an effect on the climate patterns.
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