Indian Geography — Physical Features and Climate
Free study material · concepts, shortcuts & solved questions
Why This Chapter Matters
Physical geography is one of the highest-yield sections in SSC GD and RPF Constable General Studies papers, with questions on mountain ranges, river systems, plateaus, and the monsoon appearing in nearly every set. Since RPF recruitment in particular draws candidates who will work across the length and breadth of India's rail network, a solid grasp of the country's physical landscape and climate patterns is both exam-relevant and practically useful.
Location and Extent of India
India is the seventh-largest country in the world by area, and the second-most populous. It lies entirely in the Northern Hemisphere, between latitudes 8 degrees 4 minutes North and 37 degrees 6 minutes North, and longitudes 68 degrees 7 minutes East and 97 degrees 25 minutes East. The Tropic of Cancer (23.5 degrees North) passes through the middle of the country, running through eight states — Gujarat, Rajasthan, Madhya Pradesh, Chhattisgarh, Jharkhand, West Bengal, Tripura, and Mizoram. India has a land frontier of over 15,000 km and a coastline of about 7,516 km, including its island territories. The country shares land borders with Pakistan, China, Nepal, Bhutan, Bangladesh, and Myanmar, and maritime boundaries with Sri Lanka and the Maldives, among others. Indian Standard Time (IST) is based on the longitude 82.5 degrees East, passing through Mirzapur near Allahabad, and is 5 hours 30 minutes ahead of Greenwich Mean Time (GMT).
Major Physical Divisions of India
India's landmass can be divided into six broad physiographic divisions, each with a distinct geological history and terrain character.
- The Himalayan Mountains
- The Northern Plains
- The Peninsular Plateau
- The Indian Desert (Thar Desert)
- The Coastal Plains
- The Islands
The Himalayan Mountains
The Himalayas form the youngest and highest mountain system in the world, created by the collision of the Indian Plate with the Eurasian Plate, a tectonic process that began roughly 50 million years ago and continues today, which is why the region remains seismically active. The Himalayas stretch in an arc for about 2,400 km from the Indus gorge in the west to the Brahmaputra gorge in the east, and are conventionally divided into three parallel ranges:
| Range | Also Known As | Key Features |
|---|---|---|
| Greater Himalayas | Himadri | Highest and most continuous range; contains the loftiest peaks including Mount Everest and Kanchenjunga; average height over 6,000 m |
| Lesser Himalayas | Himachal | Height 3,700-4,500 m; includes ranges like Pir Panjal, Dhaula Dhar, and Mahabharat; famous hill stations like Shimla and Darjeeling lie here |
| Outer Himalayas | Shiwaliks | Southernmost and lowest range; 900-1,100 m; composed of unconsolidated sediments; contains "duns" or flat valleys such as Dehradun |
Kanchenjunga, on the India-Nepal border in Sikkim, is the highest peak located within Indian territory, and the third-highest peak in the world. The Himalayas are also divided longitudinally, from west to east, into the Punjab Himalayas, Kumaon Himalayas, Nepal Himalayas, and Assam Himalayas.
Passes and Purpose
Important Himalayan passes include the Karakoram Pass (Ladakh), Zoji La (connecting Srinagar and Leh), Shipki La (Himachal Pradesh, on an old trade route to Tibet), and Nathu La (Sikkim, reopened for trade with China). These passes have historically served as trade and pilgrimage routes and remain strategically significant today.
The Northern Plains
South of the Himalayas lies the Northern Plain, one of the largest and most fertile alluvial stretches in the world, formed by the depositional work of three major river systems — the Indus, the Ganga, and the Brahmaputra — along with their numerous tributaries. The plain stretches for about 3,200 km from west to east and varies in width from 150 to 300 km. It is generally divided into:
- Bhabar — a narrow belt of porous, pebbly deposits just south of the Shiwaliks, where smaller streams often disappear underground.
- Terai — a wet, marshy, and forested belt south of the Bhabar, where underground streams reemerge.
- Bhangar — the older alluvium, forming terraces above the flood plains, often containing calcareous deposits known as "kankar."
- Khadar — newer, younger alluvium found in the flood plains, renewed almost every year by fresh silt deposits, making it highly fertile.
This plain supports the highest population density in India and is the country's agricultural heartland, particularly for wheat and rice cultivation.
The Peninsular Plateau
The Peninsular Plateau is one of the oldest and most stable landmasses on Earth, a relic of the ancient Gondwana continent, composed largely of ancient crystalline, igneous, and metamorphic rocks. It is triangular in shape and is bordered by the Aravalli Range in the northwest, and by the Vindhya and Satpura ranges, which divide the plateau roughly into two broad divisions: the Malwa Plateau/Central Highlands to the north, and the Deccan Plateau to the south.
Key Sub-Regions
- Central Highlands — lying north of the Narmada River, includes the Malwa Plateau, and is drained mainly by the Chambal and Betwa rivers, tributaries of the Yamuna.
- Deccan Plateau — a large triangular table-land bounded by the Western Ghats and Eastern Ghats; slopes generally from west to east, which is why most peninsular rivers (Godavari, Krishna, Kaveri) flow eastward into the Bay of Bengal.
- Western Ghats (Sahyadri) — run parallel to the western coast, more continuous and higher than the Eastern Ghats; Anaimudi in Kerala, the highest peak in Peninsular India, is located here; act as a major climatic barrier, causing heavy orographic rainfall on the windward (western) side.
- Eastern Ghats — discontinuous and eroded, running along the eastern coast, with lower average elevation than the Western Ghats; the Nilgiri Hills connect the Western and Eastern Ghats.
Two important plateaus lie between the Western Ghats and the eastern hill ranges: the Deccan Trap, formed by ancient volcanic (basaltic) activity, especially prominent across Maharashtra, which weathers into fertile black soil ("regur soil") ideal for cotton cultivation.
The Indian Desert (Thar Desert)
Lying to the west of the Aravalli Range, mainly in Rajasthan (and extending into parts of Gujarat, Haryana, and Punjab), the Thar Desert is an arid region characterized by low rainfall (under 150 mm annually in the westernmost parts), extreme temperatures, and sand dunes ("bhuj" and "dhrian"). Streams here mostly disappear into the sand or end in shallow salt lakes such as the Sambhar Lake, an important source of salt.
The Coastal Plains
India's coastline is divided into the Western Coastal Plain and the Eastern Coastal Plain.
| Feature | Western Coastal Plain | Eastern Coastal Plain |
|---|---|---|
| Location | Between Western Ghats and Arabian Sea | Between Eastern Ghats and Bay of Bengal |
| Width | Narrow | Wide |
| Nature | Submerged coast — has natural harbours like Mumbai and Kochi | Emergent coast — has deltas, fewer natural harbours |
| Sub-divisions | Konkan coast (Maharashtra-Goa), Kannad/Karnataka coast, Malabar coast (Kerala) | Northern Circars (north), Coromandel Coast (south, Tamil Nadu) |
| Notable feature | Backwaters (Kerala) | Deltas of Mahanadi, Godavari, Krishna, and Kaveri |
The Islands
India has two major island groups. The Andaman and Nicobar Islands lie in the Bay of Bengal, are of volcanic origin, and are separated from each other by the Ten Degree Channel; Barren Island, in this group, is the only confirmed active volcano in South Asia. The Lakshadweep Islands lie in the Arabian Sea, are coral in origin (formed from coral reefs and atolls), and are much smaller in total area than the Andaman and Nicobar group.
Drainage System — Major Rivers
Indian rivers are classified into Himalayan rivers (perennial, snow-fed, and rain-fed) and Peninsular rivers (mostly seasonal, rain-fed, flowing in older, shallower valleys).
| River | Origin | Outflow |
|---|---|---|
| Ganga | Gangotri Glacier (Uttarakhand) | Bay of Bengal (via Bangladesh, joins Brahmaputra) |
| Indus | Near Mansarovar Lake, Tibet | Arabian Sea (via Pakistan) |
| Brahmaputra | Near Mansarovar Lake, Tibet (as Tsangpo) | Bay of Bengal |
| Godavari | Trimbakeshwar, Maharashtra (Western Ghats) | Bay of Bengal; called "Dakshin Ganga" |
| Krishna | Mahabaleshwar, Maharashtra | Bay of Bengal |
| Kaveri (Cauvery) | Talakaveri, Karnataka (Western Ghats) | Bay of Bengal |
| Narmada | Amarkantak Plateau, Madhya Pradesh | Arabian Sea (via a rift valley, unlike most peninsular rivers) |
| Tapi (Tapti) | Satpura Range, Madhya Pradesh | Arabian Sea (via a rift valley) |
The Narmada and Tapi are notable exceptions among peninsular rivers because they flow westward through rift valleys into the Arabian Sea, rather than eastward into the Bay of Bengal like most other peninsular rivers.
Indian Climate — The Monsoon System
India has a tropical monsoon type of climate, dominated by seasonal reversal of winds. The word "monsoon" derives from the Arabic "mausim," meaning season. The Indian Meteorological Department broadly recognizes four seasons:
| Season | Approximate Months | Key Characteristics |
|---|---|---|
| Cold Weather Season (Winter) | December to February | Clear skies, low temperatures, occasional western disturbances bringing rain/snow to northwest India |
| Hot Weather Season (Summer) | March to May | Rising temperatures, low pressure develops over northwest India; "loo" (hot, dry winds) common in the plains |
| Southwest Monsoon Season (Rainy) | June to September | Bulk of India's annual rainfall; monsoon winds arrive from the sea, laden with moisture |
| Retreating/Northeast Monsoon Season | October to November | Monsoon withdraws from northwest to southeast; brings rainfall to Tamil Nadu and parts of the southeast coast |
Mechanism of the Southwest Monsoon
As summer heats the Indian subcontinent, a low-pressure zone develops over northwest India, while the relatively cooler ocean retains higher pressure. This pressure gradient draws in moisture-laden winds from the Indian Ocean, which split into two branches on reaching India:
- Arabian Sea Branch — moves northward, strikes the Western Ghats, causing heavy orographic rainfall on the windward (western) side of the Ghats, while the leeward (eastern) side, including the Deccan Plateau, remains comparatively dry (a "rain-shadow" effect).
- Bay of Bengal Branch — moves toward the northeast, is deflected westward by the Himalayas, and brings rainfall to the Northeast and the Gangetic plains; this branch is responsible for the very high rainfall recorded at Mawsynram and Cherrapunji in Meghalaya, among the wettest places on Earth.
The monsoon typically arrives at the southern tip of Kerala around the end of May or the beginning of June, and gradually advances northward and eastward, covering the whole country by mid-July. Withdrawal begins from northwest India in September and completes by around mid-December from the southern tip.
Climatic Regions and Rainfall Distribution
India's rainfall is highly uneven — ranging from over 1,000 cm annually in parts of Meghalaya to under 25 cm in the western Thar Desert. Broadly, rainfall decreases from east to west in the northern plains, and from the coast inward on the peninsula, with the interior Deccan Plateau (rain-shadow area east of the Western Ghats) receiving comparatively low rainfall despite being surrounded by wetter regions.
Major Soil Types of India
India's soils vary widely with parent rock, climate, and relief, and are broadly classified into several major types, each supporting different agricultural patterns.
| Soil Type | Where Found | Key Characteristics |
|---|---|---|
| Alluvial Soil | Northern Plains, river deltas | Most widespread and fertile; rich in potash, poor in phosphorus; ideal for wheat, rice, sugarcane |
| Black Soil (Regur) | Deccan Trap area — Maharashtra, Madhya Pradesh, Gujarat | Formed from volcanic basalt; retains moisture well; ideal for cotton, hence also called "black cotton soil" |
| Red Soil | Parts of Tamil Nadu, Karnataka, Andhra Pradesh, Odisha, Chhattisgarh | Red colour from iron oxide; less fertile than alluvial or black soil; needs irrigation and fertilizers |
| Laterite Soil | Western Ghats, parts of Kerala, Karnataka, Odisha, Assam | Formed under high temperature and heavy rainfall through intense leaching; poor in organic matter; suited to tea, coffee, cashew |
| Desert/Arid Soil | Thar Desert region | Sandy, saline, low humus content, low water retention |
| Mountain/Forest Soil | Himalayan slopes and other hilly, forested regions | Varies with altitude; generally rich in organic matter in higher rainfall areas |
Natural Vegetation
India's natural vegetation is closely tied to rainfall and temperature patterns, and is broadly grouped into the following types:
- Tropical Evergreen Forests — found in regions with heavy rainfall (over 200 cm), such as the Western Ghats, Northeast India, and the Andaman and Nicobar Islands; dense, multi-layered canopy.
- Tropical Deciduous (Monsoon) Forests — the most widespread forest type in India, found in regions with moderate rainfall (100-200 cm); trees shed leaves in the dry season; further divided into moist deciduous (e.g., sal-dominated) and dry deciduous (e.g., teak-dominated) types.
- Thorn and Scrub Forests — found in low-rainfall areas like the Thar Desert and rain-shadow regions; sparse vegetation adapted to arid conditions, such as acacia and cacti.
- Mountain Vegetation — varies by altitude in the Himalayas, from tropical forests at the base, through temperate coniferous forests, to alpine grasslands and permanent snow at the highest elevations.
- Mangrove Forests — found in tidal, saline coastal areas, most prominently the Sundarbans delta of the Ganga-Brahmaputra in West Bengal, the largest mangrove forest in the world and home to the Royal Bengal Tiger.
Key Facts at a Glance
- India lies entirely in the Northern Hemisphere; the Tropic of Cancer passes through 8 states.
- Indian Standard Time is based on 82.5°E longitude, passing near Mirzapur (Allahabad), 5:30 ahead of GMT.
- Himalayas divided into three parallel ranges: Greater Himalayas (Himadri), Lesser Himalayas (Himachal), Outer Himalayas (Shiwaliks).
- Kanchenjunga is the highest peak within Indian territory (world's third-highest overall).
- The Northern Plains are divided into Bhabar, Terai, Bhangar (older alluvium), and Khadar (newer alluvium).
- Peninsular Plateau is one of the most stable, ancient landmasses, part of the old Gondwana continent.
- Western Ghats (Sahyadri) are more continuous and higher than the discontinuous Eastern Ghats; Anaimudi is the highest peak in Peninsular India.
- Narmada and Tapi are the two major peninsular rivers flowing west into the Arabian Sea through rift valleys.
- Andaman and Nicobar Islands are volcanic in origin; Lakshadweep Islands are coral in origin.
- Southwest Monsoon (June-September) delivers most of India's annual rainfall, via the Arabian Sea and Bay of Bengal branches.
- Mawsynram and Cherrapunji in Meghalaya are among the wettest places on Earth.
- Western coast has a submerged coastline with natural harbours (Mumbai, Kochi); eastern coast is emergent, with river deltas.
Practice MCQs
- Through how many Indian states does the Tropic of Cancer pass?
- (a) 5
- (b) 6
- (c) 8
- (d) 10
- Which is the highest peak located entirely within Indian territory?
- (a) Mount Everest
- (b) Nanda Devi
- (c) Kanchenjunga
- (d) K2
- The Shiwalik range is also known as:
- (a) Himadri
- (b) Himachal
- (c) Outer Himalayas
- (d) Trans-Himalayas
- Which alluvial deposit in the Northern Plains is renewed almost every year by fresh silt?
- (a) Bhangar
- (b) Khadar
- (c) Bhabar
- (d) Terai
- Which mountain range forms the border between the Central Highlands and the Deccan Plateau?
- (a) Aravalli
- (b) Vindhya-Satpura
- (c) Western Ghats
- (d) Nilgiri
- Which is the highest peak in Peninsular India?
- (a) Dodabetta
- (b) Anaimudi
- (c) Mahendragiri
- (d) Guru Shikhar
- Which two major peninsular rivers flow westward into the Arabian Sea?
- (a) Godavari and Krishna
- (b) Narmada and Tapi
- (c) Kaveri and Godavari
- (d) Mahanadi and Krishna
- The Andaman and Nicobar Islands are of which origin?
- (a) Coral
- (b) Volcanic
- (c) Alluvial
- (d) Glacial
- Which branch of the Southwest Monsoon is responsible for very high rainfall in Meghalaya?
- (a) Arabian Sea Branch
- (b) Bay of Bengal Branch
- (c) Northeast Monsoon
- (d) Western Disturbance
- India's Standard Time meridian (82.5° E) passes near which city?
- (a) Delhi
- (b) Mirzapur
- (c) Bhopal
- (d) Nagpur
- Which state has the Malabar Coast as part of its coastline?
- (a) Maharashtra
- (b) Karnataka
- (c) Kerala
- (d) Tamil Nadu
- Which season, per the Indian Meteorological Department's classification, spans June to September?
- (a) Cold Weather Season
- (b) Hot Weather Season
- (c) Southwest Monsoon Season
- (d) Retreating Monsoon Season