From March to May, conditions are generally dry. Temperatures begin to rise, heating the land mass, and forming areas of low pressure.
Hot, wet season, June–September: High temperatures create low pressure, drawing the rain-bearing trade winds inland (Fig. 22.5). This is the wet season. In north-east India, the Himalayas act as a barrier and cause relief rain.
Tibetan Plateau
Fig. 22.5 Pressure pattern for the hot, wet season in India.
Mean temperature (°C) Mean precipitation (mm) 14
22 22
Fig. 22.6 High temperatures and low pressure bring heavy rains to much of India in the summer.
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 19.5
27 28
29.9 51
30.4 126
29.7 301
28.7 375
28.6 339
28.9 305
27.4 141
23.3 26
Table 22.1 Average monthly temperature and precipitation, Kolkata (Climate-Data.Org).
SKILLS ACTIVITY
Construct a suitable graph to illustrate the precipitation data from April to October in Table 22.1.
Relief and drainage The Indian subcontinent contains a number of different physical regions with distinctive landscapes and drainage patterns.
19.5 7
DID YOU KNOW?
During the monsoon season in India, it is common to see a mouse on the back of the frog. They do this to escape the floodwaters.
