IAS Prelims Geography Q.15 – 2024 | World Climate Types
Authentic Classroom Explanation by IAS Monk
📍 The Question
Consider the following description:
- Annual and daily range of temperatures is low.
- Precipitation occurs throughout the year.
- Precipitation varies between 50 cm – 250 cm.
What is this type of climate?
(a) Equatorial climate
(b) China type climate
(c) Humid subtropical climate
(d) Marine west coast climate
Correct Answer: (d) Marine west coast climate
🎯 Theme of the Question
Physical Geography | Climatology | World Climate Types | Westerlies
This question tests recognition of climatic characteristics, especially temperature range, rainfall pattern, and atmospheric circulation.
🧠 Classroom Explanation
Let us analyse the clues given in the description.
🔹 Low annual and daily temperature range ✅
- Indicates:
- Strong maritime influence
- Absence of temperature extremes
- Oceans moderate both summer heating and winter cooling
This rules out:
- Continental climates
- Equatorial climates (high daily range)
🔹 Precipitation throughout the year ✅
- Suggests:
- No dry season
- Continuous supply of moist air
- Typical of regions under the influence of:
- Westerlies
- Frequent cyclonic systems
🔹 Rainfall between 50 cm – 250 cm ✅
- Wide range but consistently moderate to high
- Often occurs as:
- Drizzle
- Prolonged light rain
- Foggy precipitation
- Linked to cyclonic disturbances embedded in the Westerlies
🌍 Identifying the Climate Type
All three conditions together point clearly to the Marine West Coast Climate (also known as the British Type Climate).
🌐 Distribution of Marine West Coast Climate
- North America:
Coastal Oregon, Washington, British Columbia, southern Alaska - South America:
Coastal Chile - Europe:
Northwestern Europe (extended inland due to mountain orientation) - Oceania:
Southeastern Australia, New Zealand
📊 Key Climatic Features
| Feature | Marine West Coast Climate |
|---|---|
| Temperature range | Low |
| Rainfall | Throughout the year |
| Rainfall amount | 50–250 cm |
| Winds | Westerlies |
| Dominant systems | Cyclonic storms |
👉 Correct answer: (d)
❌ UPSC Elimination Logic
- Equatorial climate → very high rainfall but high daily temperature range
- China type climate → monsoonal, seasonal rainfall
- Humid subtropical → higher temperature range, summer rainfall dominance
- Only Marine West Coast satisfies all three conditions together
🧩 Memory Hook
“Soft rains, soft summers, soft winters — the ocean smooths everything.”
🧠 Prelims Strategy Insight
For climate identification:
- Match temperature range + rainfall distribution
- Presence of Westerlies + oceans = Marine West Coast
- Uniform rainfall is the biggest clue
🧭 IAS Monk Whisper
Where oceans guide the winds, extremes quietly disappear.