Why the winter monsoon in East Asia is stronger than the summer monsoon; The summer monsoon in South Asia is stronger than the winter monsoon.

The main reason is the difference of thermal properties between land and sea.

There are obvious thermal differences between Asia and the Pacific. In winter, a cold high pressure formed in Mongolia and Siberia cut off the sub-polar low pressure belt. There is a pressure gradient force among Mongolian high, Pacific low and equatorial low, which is influenced by geostrophic bias to form an anticyclone, and the northerly wind moves south, affecting a large area of East Asia, which is an East Asian winter wind.

In summer, a thermal depression forms in India, cutting off the subtropical high. On the ocean where the subtropical high is broken and reserved, there is a high pressure center in the North Pacific, and the southerly airflow of the North Pacific high affects East Asia, which is the East Asian summer monsoon.

Extended data:

Asian atmospheric heat source centers are mainly located in the Bay of Bengal, the South China Sea and the west coast of India, not over the Qinghai-Tibet Plateau. East Asian monsoon has low frequency oscillation and interannual oscillation for 30-60 days. The East Asian subtropical low-frequency oscillation propagates from east to west and from south to north, and converges with the oscillation at middle and high latitudes to the south at about 30.

East Asian monsoon is caused by the difference of thermal properties between land and sea. In summer, the land temperature is high, forming a low pressure, and the summer monsoon blows from the subtropical ocean to the land (southerly wind); In winter, the cold land forms high pressure, so the winter wind blows from the high latitude mainland to the ocean (northerly wind), and the winter wind is strong. The main reason is the difference of thermal properties between land and sea. Its scope includes eastern China, Korean Peninsula, Japanese and other regions.

Baidu encyclopedia-East Asian monsoon