Authentic Classroom Explanation by IAS Monk

📍 The Question

Consider the following description:

1. Annual and daily range of temperatures is low.
2. Precipitation occurs throughout the year.
3. 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

👉 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.