Highest precipitation on the east and west coasts of peninsular India
The west coast has more precipitation than the east coast
Most areas in South Asia are located north of the equator and south of 30° north latitude. Except for the Maldives Islands and the southern part of Sri Lanka, which are close to the equator, they have a tropical rainforest climate. Except for northwest India and southern Pakistan, which have a tropical desert climate, most other areas have a tropical monsoon climate.
The formation of the South Asian monsoon climate is closely related to the thermal difference between the sea and the land in winter and summer, the seasonal displacement of the planetary wind belt, and the topography of the Tibetan Plateau. According to the advance and retreat of the monsoon, the year can be divided into three seasons: cool, hot and rainy. From December to February, the northeast monsoon blowing from the mainland to the ocean brings clear, dry, and cool weather, which is the cool season. In the cool season, the daily temperature range is large, there is a certain amount of cyclonic rain in the northwest, and there is more precipitation on the east coast of the peninsula. From March to May, as the direct sun point moves northward, the temperature increases rapidly and the climate is hot and dry, which is called the hot season. The temperature in the central Deccan Plateau reaches 35°C, and the absolute highest temperature in the Thar Desert has reached over 50°C, with sandstorms sometimes occurring. From June to September, due to the continuous high temperature in South Asia, a thermal low pressure is generated in northwest India, which strongly attracts the southwest monsoon deflected by the southeast trade wind across the equator.
Thus, the power of the southwest monsoon is further strengthened. The southwest monsoon passes through the vast warm tropical ocean and is full of water vapor, bringing abundant precipitation to most parts of South Asia, forming the rainy season. 90% of annual precipitation occurs in the rainy season.
The onset of the rainy season is earliest in the west of the peninsula and latest in northwest India. The late arrival and early departure of the southwest monsoon is a major reason for the large rainfall variability in South Asia. October to November is the end of the rainy season. The temperature begins to gradually decrease and the air pressure in the northern area gradually increases. As a result, the pressure gradient between the sea and the land gradually weakens. Therefore, the southwest monsoon begins to retreat and precipitation decreases. It will soon turn into the cool season.
Indian Tropical Rainforest
Tropical monsoon forest occupies a vast area, and its distribution is closely related to precipitation. The western side of the Western Ghats, the southern side of the eastern Himalayas, the Assam region and most of Sri Lanka have annual rainfall of more than
2,000 mm, which is a tropical rainforest area; most of the Deccan Plateau The annual precipitation is 1,000 to 2,000 millimeters. In order to reduce evaporation in the hot season, trees shed leaves in the dry season; in the interior of the Deccan Plateau and the northwest of the Indian Peninsula
the annual precipitation is between 500 to 1,000 millimeters. , between 000 mm, mostly shrubs and grassland vegetation; the Thar Desert and its surroundings receive very little rainfall and are deserts and semi-deserts, with only sparse herbaceous plants and thorny shrubs growing.