Does "Indo-Pak subcontinent" refer to the entire South Asia?

Yes, the Indo-Pak subcontinent is the South Asian subcontinent.

South Asia is the southern part of Asia, including from the south side of the western and middle sections of the Himalayas to the Indian Ocean

vast area. Usually refers to countries such as Pakistan, India, Bangladesh, Nepal, Sikkim, Bhutan, Sri Lanka, Maldives and the Kashmir region. Since the Himalayas separate South Asia from the rest of Asia, South Asia forms a relatively independent unit geographically, so it is also called the South Asia subcontinent, or subcontinent. .

The boundaries of this region are clear, with young new fold mountains (such as the Sulaiman Mountains in the northwest, the Karakoram Mountains in the north, the Himalayas, and the Badakai Mountains in the east). and Arakan Mountains, etc.), surrounding the peninsula in the north, facing the sea in the south, with a distance of about 3,100 kilometers from north to south and east to west, and an area of ??about 4.3 million square kilometers.

Geological structures and topography have a very obvious relationship. The Deccan Plateau in the south, which occupies most of the Indian Peninsula

, is a huge ancient land mass of the Precambrian period. It is the core of the subcontinent and is the Gangnam part of that ancient continent. At the end of the Cretaceous, large-scale basalt overflow occurred in the northwest of the Deccan Plateau, covering an area of ??400,000 square kilometers, forming the largest lava platform in the world. The topography of the Deccan Plateau is

a large ancient block that has been eroded for a long time and slopes gently to the northeast. The Western Ghats constitute the western edge of the plateau.

The height is about 1,000~ 1,500 meters, with its western slope forming a fault cliff; the Eastern Ghats forms the eastern edge of the plateau, with a height of about 500 to 600 meters. It is in the shape of a low hill, and there is a wider coastal plain along the coast; There are many horsts and trenches in the Deccan Plateau. In short, the Deccan Plateau is an ancient, eroded, tilted, peneplain and hilly massif cut by many rivers. As for the island of Sri Lanka, it was originally integrated with India in terms of geological structure. It was later separated from India due to the subsidence of the Palk Strait and the Gulf of Mannar. The north is a part of the mountainous area on the southern side of the Himalayas, which is the product of the Himalayan movement. The Himalayas can be divided into three belts structurally: the northern belt, also known as the Tibetan belt or the Tibetan Himalayan belt, is a rock formation from the early Paleozoic to the Tertiary. Composition; the central zone, also known as the Snow Peak Himalayan Zone or the Himalayan Zone,

The exposed rocks are mainly granite and gneiss, with many modern glaciers and snow peaks; the southern zone is also known as the Outer Zone or

The Piedmont Himalayan Zone, located between the Indian Great Plains and the Himalayas, is mainly low foothills.

The rock formations are mainly Tertiary sedimentary rocks, with a height of about 1,000 meters. The Indian Great Plains belongs to the New Fold Mountains.

The foredeep zone was formerly part of the Bay of Bengal and the Arabian Sea. It is about 3,000 kilometers long from east to west and about 250 kilometers wide from north to south. 300 kilometers, it is one of the world's famous great plains.

Most of South Asia is located north of the equator and south of 30° north latitude, except for the Maldives Islands and Sri Lanka.

The southern part of Lanka Island is close to the equator and has a tropical rainforest climate. Northwest India Except for the tropical desert climate in southern Pakistan, 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

in 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

there is a large daily temperature range, 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 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 maximum temperature in the Thar Desert has reached over 50°C, and sometimes

sandstorms occur. 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 that is deflected by the southeast trade wind across the equator, thus causing the southwest monsoon< /p>

The power is further strengthened. The southwest monsoon passes through the vast warm tropical ocean, is full of water vapor, and brings abundant precipitation to 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 western part of the peninsula and latest in northwestern 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, so the southwest monsoon begins.

begins to shrink, the precipitation decreases, and it soon turns into the cool season.

Tropical rain forests and tropical monsoon forests occupy a large area, and their 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, making them tropical areas. Rainforest area; the annual precipitation in most of the Deccan Plateau is 1,000 to 2,000 mm. In order to reduce evaporation in the hot season, trees lose their leaves in the dry season; within the Deccan Plateau

< p>The northern part of the Indian Peninsula and the northwest of the Indian Peninsula have annual precipitation between 500 and 1,000 mm, and are mostly shrubs and grasslands

Vegetation; the Thar Desert and its surroundings have very little rainfall and are deserts and Semi-desert, only sparse herbaceous plants and thorny shrubs grow.