Introduction: India's Climatic Setting

Climate is the average atmospheric condition of a region over a long period (typically 30 years). India's climate is fundamentally defined by two overriding factors: (1) its tropical location (8°N–37°N) giving it abundant solar radiation, and (2) the monsoon system which concentrates 70–90% of the country's annual rainfall into the four-month SW monsoon season (June–September).

Four factors controlling India's climate:

1. Latitude: India spans tropical to sub-tropical zones; Tropic of Cancer (23.5°N) passes through middle India, dividing it into tropical (south) and sub-tropical (north) regions. Southern India has uniformly high temperatures throughout the year; northern India has distinct seasons.

2. Himalayas: Act as a climatic barrier blocking cold Central Asian air masses (preventing harsh Siberian winters from reaching the Indo-Gangetic Plain); also force monsoon winds to deposit their moisture on the Indian subcontinent.

3. Distance from the sea: Peninsular India is never far from the sea — has maritime influence, moderate temperatures. Central India (MP, UP) is far from both coasts — more continental climate with extreme temperatures.

4. Relief: Western Ghats force heavy orographic rainfall on their windward (western) face but create a rain-shadow zone on their leeward (eastern) side — the Deccan Plateau interior receives 500–700 mm while the western coast receives 2,500–4,000 mm.

India's average annual rainfall: 1,187 mm (among the world's highest for a large country). But this figure is an average — actual ranges are 150 mm (Jaisalmer) to 11,871 mm (Mawsynram).

---