The climatic conditions in India have the following salient features:
1. The Reversal of Winds:
The climate of India is characterised by the complete reversal of the wind system with the change of seasons. During the winter season, the winds generally blow from northeast to southwest (land to sea), while in summer season the winds blow from southwest to northeast (sea to land).
2. Development of High and Low Pressure Areas:
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During the winter season, due to low temperature, high pressure area is formed over the northern part of the India. On the other hand, during the summer season, due to high temperature, thermally induced low pressure area is formed over the north-western part of India.
These alternate high and low pressure areas control the direction, intensity and flow of winds in the respective seasons. That is why the winds are generally offshore and dry during the winter season and onshore and wet during the summer season.
3. Seasonal and Variable Rainfall:
The amount of annual rainfall received in various parts of India varies just not regionally, but also seasonally.
About 80 per cent of the total rainfall is received during the short rainy season (June to September). As the rainfall is in the form of heavy downpour, it creates problems of floods and soil erosion. Sometimes there is continuous rainfall for many days and sometimes there is a long dry spell.
4. Multiple Seasons:
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A constant and continuous change of weather has been observed over India. Although there are three main seasons summer, winter and rainy, but in many parts the number may go up to six seasons. This multiplicity of seasons shows the quick changing nature of weather conditions in India.
5. Natural Calamities:
Due to the variations in the amount of rainfall in different parts of India, natural calamities like floods, droughts, famines and epidemics are quite common.
Continuous rains may cause devastating floods while the failure of the rains may lead to severe drought conditions.
The variability in the climatic conditions helps in the cultivation of a number of crops belonging to tropical, temperate as well as frigid areas.