Causes of hot season in South Asia

The reason for the summer heat in South Asia is not because of the lack of precipitation. On the contrary, South Asia has a tropical monsoon climate with high temperature and rainy summer. For example, Bangladesh, located in the Ganges Delta, often suffers from floods.

South Asia is influenced by equatorial low pressure belt and northeast trade wind belt all the year round. (However, the formation of the south subtropical monsoon climate is also influenced by the difference of thermal properties between land and sea. )

The equatorial low pressure area is about north and south latitude 10 degrees, and the trade wind area is about north and south latitude 10 to 25 degrees. The tropical monsoon climate is roughly north latitude 15-25 degrees. Only South Asia in the world has a tropical monsoon climate. )

In June, July and August in the northern hemisphere, the sun shines directly near the Tropic of Cancer, and the equatorial low pressure belt and the trade wind belt move northward. At this time, the trade winds move northward, and can no longer dominate at the north latitude 15-25 degrees, while the equatorial low pressure belt controls the area, forming the rainy season. (rainy season)

When the northern hemisphere is not in June, July and August, the direct point of the sun is far away from the Tropic of Cancer, so that the latitude of north latitude 15-25 degrees is still dominated by the trade winds, and the equatorial low pressure area cannot control this area, thus forming a dry season. (dry season)

It should be noted that heat is not dry. Therefore, it is not unusual for South Asia to be hot and rainy in summer.

The failure of the summer monsoon is not necessarily related to whether it is hot or not.