Please explain that South Asia and Southeast Asia have tropical monsoon climate, but there are differences. What are these differences?

South Asia and Southeast Asia, including the Indian Peninsula, the middle and lower reaches of the Ganges and the Brahmaputra River basin, Indochina Peninsula and the Philippine Islands, belong to a tropical monsoon climate, with a typical latitude of 6 ~ 20. The air mass that dominates the climate in this area is the equatorial air mass in wet season (June-September). Under the joint action of Tagg depression and equatorial westerly wind, the southwest monsoon blows, and the wind force is stronger than the east Asian summer monsoon, which brings wet and rainy weather. For example, 80% or even 90% of the annual precipitation in South Asia (western India) falls in the summer monsoon period; The dry season (11~ April) is a tropical air mass, and the northeast monsoon prevails, belonging to the tropical trade wind, accompanied by dry weather. Before the establishment of the southwest monsoon, that is, before the arrival of the rainy season, the Indian Peninsula and Indochina Peninsula (except Laos and northern Vietnam) were the hottest periods-the hot season (usually from March to May, the hottest in May), and the average temperature in the hottest month was 25 ~ 30℃. The northern boundary of this area is equivalent to the position of tropical front in summer, which is roughly consistent with the most Leng Yue average temperature of 65438 08℃. Winter and summer monsoon alternate, and each year is divided into dry season and rainy season. The hottest month is before the wet season, with strong summer monsoon, strong explosiveness, abundant precipitation and large variability. These characteristics are the same as those of tropical monsoon climate zone.

Due to the influence of location, area and topography related to land and ocean, there are some differences within the tropical monsoon climate zone, which can be mainly divided into continental type and ocean type. The former is located in the South Asian subcontinent and Indochina Peninsula. Because the coastal mountains block the sea breeze, and the bases of Indian Peninsula and Indochina Peninsula are close to the vast mainland, the temperature can reach 20℃ throughout the year, and the dry season is longer than the rainy season, and the hot season is prominent. The latter is located on the coast of Philippine Islands and Indochina Peninsula, where there is abundant precipitation in both winter monsoon and summer monsoon, and the annual range and diurnal range are smaller than those of Indian Peninsula, especially in dry season.

Compared with the monsoon climate in Southeast Asia, the tropical monsoon climate in the South Asian subcontinent has its own characteristics. On the basis of the annual dry and wet season, there is also a prominent hot season (March to May). For example, the average temperature in Madras from April to August exceeds 30℃, and the highest temperature in Alba has reached 50.6℃. The establishment of southwest monsoon is about 1 month later than that of Indo-China Peninsula, and the precipitation variability is large. For example, the annual precipitation in the Ganges Plain ranges from 150mm to 65438+.