Chapter Notes: Asia Physiography

Introduction

Asia, the largest continent on Earth, stands out for its vast land area and huge population. It covers about 30% of the world's land and hosts around 60% of its people, with China and India being home to most of them. The continent's physical geography is diverse, shaped by tectonic plate movements that formed towering mountains and active volcanoes, especially around the Pacific Ocean. From serene coastlines and icy peaks to lush jungles and bustling cities, Asia offers a stunning mix of landscapes and cultures.

Location

• Stretches from 10°S to 80°N latitude and 25°E to 170°W longitude.
• North-south distance spans 8,560 kilometers.
• East-west stretch covers about 9,600 kilometers.
• Bounded by the Arctic Ocean in the north.
• Pacific Ocean lies to the east, Indian Ocean to the south.
• Mediterranean Sea and Black Sea border the southwest.
• Europe lies to the west, separated by the Ural Mountains, Caspian Sea, Caucasus Mountains, and Black Sea.
• Bering Strait separates Asia from North America in the northeast.
• Seas and straits between the Indian and Pacific Oceans separate Asia from Australia in the southeast.
• Isthmus of Suez connects Asia to Africa, with the Suez Canal as the border.
• Bosphorus and Dardanelles straits separate Anatolia from the Balkan Peninsula.

Countries in Asia

• Consists of 49 sovereign states.
• Includes 6 states with limited international recognition.
• Has 6 dependent territories.

Regional Divisions of Asia

Divided into regions since the 18th century, though not based on strict historical consensus.

East Asia

• Eastern sub-region of Asia, both geographically and geopolitically.
• Includes China (with Hong Kong and Macau), Mongolia, North Korea, South Korea, Japan, and Taiwan.
• Covers about 28% of the continent.

North Asia

• Encompasses Siberia and the Asia-Pacific region of Russia.

Central Asia

• Stretches from the Caspian Sea in the west to western China in the east.
• Includes former Soviet Republics: Azerbaijan, Armenia, Georgia, Kazakhstan, Turkmenistan, Uzbekistan, Kyrgyzstan, and Tajikistan.

South-East Asia

• Consists of Brunei, Cambodia, East Timor, Indonesia, Laos, Malaysia, Myanmar, Philippines, Singapore, Thailand, and Vietnam.

South Asia

• Includes Afghanistan, Bangladesh, Bhutan, Maldives, Nepal, India, Pakistan, and Sri Lanka.
• Covers about 11.51% of the continent.
• Supports one-fourth of the world's population, making it the most densely populated region globally.

West Asia

• Comprises Saudi Arabia, Yemen, Oman, Bahrain, United Arab Emirates, Kuwait, Iraq, Iran, Jordan, Syria, Israel, Lebanon, and Turkey.

Physical Regions of Asia

Asia can also be divided into five major physical regions: 

• Northern Lowlands 
• Central Highlands 
• Southern Plateaus 
• Great River Basins 
• Island Groups

Northern Lowlands

• Stretch from the Ural Mountains in the west to the Bering Sea in the northwest.
• Form the world's greatest continuous plain.
• Lie between the Arctic Ocean in the north and Central Mountains in the south.
• Created by the Ob, Yenisei, and Lena rivers.
• Northern part known as the Siberian Plain.
• Turan Plain, south of the Siberian Plain, surrounds the Aral Sea and features inland drainage.
• Lake Baikal, the world's oldest and deepest lake, is located here.

Central Highlands

• Contain numerous mountain ranges meeting at the Pamir Knot.
• Ranges radiating from the Pamir Knot: Himalayas, Hindu Kush, Karakoram, Kunlun Mountains, and Tien Shan.
• Pamir Knot connects to the Armenian Knot via the Elburz and Zagros Ranges.

Himalayas

• World's highest mountain range, north of the Indian subcontinent.
• Separates India from the rest of Asia.
• Home to major rivers watering the Indian subcontinent.
• Includes Mount Everest (8,848 meters) and Kanchenjunga (8,586 meters).
• Has over 100 peaks exceeding 7,200 meters.

Hindu Kush Mountains

• Part of the alpine zone stretching across Eurasia.
• Separate the Pamir Mountains near the borders of China, Kashmir, and Afghanistan.
• Merge into smaller ranges in western Afghanistan.
• Highest peak is Mount Tirich Mir at 7,690 meters.

Karakoram Range

• Spans Pakistan, India, China, Afghanistan, and Tajikistan.
• Located in Gilgit-Baltistan (Pakistan), Ladakh (India), southern Xinjiang (China), and the Wakhan Corridor (Afghanistan).
• Hosts four peaks over 8,000 meters: K2 (8,611 meters), Gasherbrum I, Broad Peak, and Gasherbrum II.

The Kunlun Mountains

• One of Asia's longest mountain chains, crossing western China and the Tibetan Plateau.
• Highest peak is Kunlun Goddess at 7,167 meters.
• Border the Gobi Desert.

Tien (or Tian) Shan

• Large mountain system in Central Asia.
• Lies north and west of the Taklamakan Desert, near Kazakhstan, Kyrgyzstan, and western China.
• Highest peak is Victory Peak at 7,439 meters.

Altay (or Altai)

• Located in East-Central Asia near southern Siberia.
• Where Russia, China, Mongolia, and Kazakhstan meet.
• Irtysh and Ob rivers originate here.
• Highest peak is Belukha Mountain at 4,506 meters.
• Key habitat for the snow leopard, a vulnerable species.

Zagros

• Largest mountain range in Iran and Iraq.
• Spans the western and southwestern Iranian plateau, ending at the Strait of Hormuz.
• Highest point is Mount Dena at 4,409 meters.

Pamir Mountains

• Form an ocean of white and blue peaks and valleys, some over 7,000 meters.
• Lie at the junction of the Himalayas, Tien Shan, Karakoram, Kunlun, and Hindu Kush ranges.
• Highest point is Ismoil Somoni Peak at 7,495 meters.
• Feature intermontane plateaus, like the Tibetan Plateau, between mountain ranges.
• Tibetan Plateau, the "roof of the world," lies between the Kunlun Range and Himalayas.
• Other plateaus: Iranian, Anatolian, and Mongolian.
• Include two great depressions: Tarim Basin and Tsaidam Basin.

Southern Plateaus

The Southern Plateaus lie to the south of the Central Mountains. The Deccan Plateau, the Arabian Plateau, and the Shan and Yunnan Plateaus are the prominent plateaus of this region. These plateaus are made up of old hard crystalline rocks.
Deccan Plateau

• Large plateau in southern India.
• Steep along the Arabian Sea coast in the west, gently sloping toward the Bay of Bengal in the east.
• Rises to 100 meters in the north and over 1,000 meters in the south.
• Rivers like Mahanadi, Godavari, Krishna, and Kaveri flow through it.
• Extends over eight Indian states.
• Lies between the Western Ghats and Eastern Ghats, converging near India's southern tip.

Arabian Plateau

• Steep in the west, gently sloping eastward to the Persian Gulf.
• Very dry, with little rainfall and no rivers.

Shan Plateau

• Crystalline massif in eastern Myanmar, part of the Indo-Malayan mountain system.
• Crossed by the deep Salween River trench in the east.
• Bordered by the upper Irrawaddy River in the west.
• Average elevation between 750 and 1,200 meters.

Yunnan Plateau

• Highland region in northern Yunnan and western Guizhou provinces, south-central China.
• Elevation around 2,000 meters.
• Mountain peaks in the west rise above 3,700 meters.

Great River Basins

The presence of several snow-clad mountains in Asia has given rise to many perennial rivers. The valleys of these rivers are very fertile. Therefore, the population around these areas is denser as compared to other regions. These valleys are situated between the central mountain ranges and the southern plateaus. Some prominent river valleys are given below.

Tigris-Euphrates Valley

• Formed by the Tigris and Euphrates rivers flowing southeast through Iraq.

Indus Valley

• Created by the Indus River and its five tributaries in Pakistan and India.

Ganga-Brahmaputra Valley

• Formed by the Ganga and Brahmaputra rivers flowing through India and Bangladesh.

Irrawaddy-Salween-Mekong Valley

• Shaped by the Irrawaddy, Salween, and Mekong rivers flowing through Myanmar and neighboring countries.

Great Plains of China

• Land formed by the Huang He, Chang Jiang, and Si Kiang rivers.

Island Groups

The eastern and the south-eastern part of Asia has several island chains. A group of islands is known as an archipelago.
Malay Archipelago

• World's largest group of islands.
• Includes over 17,000 islands of Indonesia and about 7,000 islands of the Philippines.
• Stretches over 6,100 kilometers along the Equator and 3,500 kilometers north to south.
• Lies between the Pacific and Indian Oceans.
• Includes Borneo, Sumatra, Java, Sulawesi, Bali, and Timor.

Lakshadweep and Andaman & Nicobar Islands

• Lakshadweep Islands lie in the Arabian Sea, belonging to India.
• Andaman and Nicobar Islands are in the Bay of Bengal, also part of India.

Kuril Islands

• Archipelago of over 30 mountainous islands.
• Run north from Hokkaido (Japan) to the Kamchatka Peninsula (Russia).
• Enclose the Sea of Okhotsk, covering 15,600 square kilometers.

Japanese Archipelago

• Forms Japan, with islands Hokkaido, Honshu, Shikoku, and Kyushu.
• Extends northeast to southwest along the Pacific Ocean.

Deserts

A significant portion of Asia is covered by deserts that are hot and arid like the Arabian Desert or cold like the intercontinental deserts of Central Asia.

Arabian Desert

• Vast desert stretching from Yemen to the Persian Gulf, and Oman to Jordan and Iraq.
• Largest desert in Asia, covering 2.33 million square kilometers.
• Occupies most of the Arabian Peninsula in the Middle East.

Gobi Desert

• Second largest desert in Asia, spanning 1.295 million square kilometers.
• Extends from northern China into Mongolia.
• Receives about 7 inches of rainfall yearly, blocked by the Himalayas.

Taklamakan Desert

• China's largest desert, covering 337,000 square kilometers.
• Features shifting crescent sand dunes, one of the world's largest sandy deserts.

Thar Desert

• Asia's only subtropical desert, covering 200,000 square kilometers in India and Pakistan.
• Mainly in Rajasthan, India.
• Receives up to 20 inches of rain yearly, mostly during the monsoon from July to September.
• Most crops grow during the rainy season.

Water Bodies

Some of the most magnificent water bodies can be found in Asia. A few of them have been briefly discussed below:

Caspian Sea

• Located in western Asia, on the eastern edges of Europe.
• Largest lake on the planet, with a surface area of 371,000 square kilometers.
• Oil and gas platforms line its edges.
• Receives fresh water from the Volga and Ural rivers but remains salty.

Lake Baikal

• In southeastern Russia, north of Mongolia.
• Oldest existing freshwater lake and deepest continental body of water at 5,315 feet.
• Stretches about 626 kilometers in length.

Aral Sea

• Located in Kazakhstan and Uzbekistan, east of the Caspian Sea.
• Shrinking due to pollution from fertilizer runoff and Soviet-era weapon testing and industrial projects.