SSC CGL Geography · Climatology, Atmosphere and Weather
Climate Types and Rainfall
What controls a climate, Koeppen's letters and India's climate types, and how moisture becomes rain: humidity, the three kinds of rainfall, and how rain is measured.
Why this matters
Fourteen questions in the bank: six from the 2023 shifts, five from the 2024 shifts and three from the 2025 shifts, 11 of them EASY. Several are 'which of these is NOT a control (or an element)' questions, so learn the two short lists exactly.
Concept 1 of 2: Climate controls and climate types
Definition
Elements of weather: temperature, pressure, humidity, wind, cloud and precipitation. (Soil pH is not one.)
Controls of climate: latitude, altitude and relief, distance from the sea, ocean currents, and pressure and winds. (The type of soil and the Earth's interior are not.)
Continentality: places far from the sea have very hot summers and very cold winters.
Zones: the tropics barely change temperature through the year; temperate zones have four seasons.
Koeppen's letters: A tropical humid, B dry, C warm temperate, D cold snow-forest, E polar. In India:
- Cwg: monsoon with a dry winter, over most of the Ganga plain.
- E: polar type, on the high Himalayas.
- Montane climate belongs to the Himalayan States (Jammu and Kashmir, Himachal Pradesh, Uttarakhand), not to Uttar Pradesh or Bihar.
Practise this conceptself-check · 4 quick reps
The same idea in a real exam question:
Example 1 · Climatology, Atmosphere and Weather · Climate Types and Rainfall
Montane climate is Himalayan
Concept 2 of 2: Humidity and rainfall
Definition
The facts:
- Humidity is the water vapour in the air. When vapour condenses on smoke or dust over a city, the result is smog.
- Convectional rain: the ground heats the air, which rises and cools.
- Orographic rain: a mountain forces moist air up. The windward side gets the rain; the leeward side lies in the rain shadow.
- Frontal (cyclonic) rain: warm air is lifted over cold air at a front.
- Rainfall is measured as a depth, in millimetres. A Doppler weather radar detects rain and measures its speed and strength.
| Kind of rain | Why the air rises |
|---|---|
| Convectional | Heated by the ground |
| Orographic | Pushed up a mountainQ |
| Frontal (cyclonic) | Lifted over colder air |
Practise this conceptself-check · 4 quick reps
The same idea in a real exam question:
Example 2 · Climatology, Atmosphere and Weather · Climate Types and Rainfall
Pressure units are not rainfall units
Summary — formulas & gotchas at a glance
A revision cheat-sheet for the formulas and gotchas above. Click any concept name to jump back to its full explanation.
Reference tables (2)
Humidity and rainfall3 rows
| Kind of rain | Why the air rises |
|---|---|
| Convectional | Heated by the ground |
| Orographic | Pushed up a mountainQ |
| Frontal (cyclonic) | Lifted over colder air |
Watch out for (2)
- Montane climate is Himalayan→ Climate controls and climate types
- Pressure units are not rainfall units→ Humidity and rainfall
Test yourself on Climatology, Atmosphere and Weather
15 past SSC CGL questions from this chapter, timed at 9 minutes and marked the way the exam marks it. You see your score and every answer the moment you finish. Free to start.