Geography, GS-1, Uncategorized

Explained: Koppen Method of Climate Classification

The three methods of classification of climate by Koppen, Trewartha and Thornthwaite are very frequently asked in the UPSC Geography Optional Paper 1. I had made notes for such high frequency topics. This topic should be studied comparatively to remember the three methods. I will list out Koppen’s method of classification and compare Trewartha and Thornthwaite with it.

Koppen’s Classification of Climate

  • It is empirical (based on observation) and not genetic (based on origin)
  • Based on Candolle’s vegetation Zones
  • Average annual precipitation and monthly temperature & precipitation values are the criteria

5 Major Types and their sub-types

  1. A: average monthly temperature always above 18 degrees. Tropical region
  2. B: Moisture/ Rain deficit. Evaporation exceeds precipitation
  3. C: Humid, mesothermal, mid-latitude, coldest month between 3-13 degrees
  4. D: Humid microthermal, coldest month 3 degree or below. Warmest month 10 degree or above
  5. E: Polar climate. Warmest month <10 degree

Other letter code

These codes are fairly intuitive. If you learn them, it will be easier to remember the entire classification.

  1. f: rain throughout the year
  2. w: winter dry
  3. m: monsoon
  4. s: summer dry
  5. h: hot
  6. k: cold

Detailed Koppen Classification of Climates

  • Type A
    • Af: Equitorial rainforest (A= tropical, f= always rain; easy peasy!)
    • Aw: Savanna type (winter dry tropical region)
    • Am: Monsoon type (short dry season, adequate rainfall)
    • As: Summer Dry (rare)
  • Type B
    • BS: Steppe Type semi-arid (less
      • BSh: avg. annual temperature >18 degrees (tropical Steppe)
      • BSk: avg. annual temperature <18 degrees (mid-latitude Steppe)
    • BW: dry desert climate (more extreme)
      • BWh:  avg. annual temperature >18 degrees
      • BWk: avg. annual temperature <18 degrees
  • Type C
    • Cf: Western European Type
    • Cs: Dry summer, 3x precipitation in winter. Mediterranean Climate
    • Cw: Dry Winter. 10x ppt. in summers. China type climate
  • Type D
    • Df: no dry season
    • Dw: winter dry season
  • Type E
    • ET: Tundra type, 0-10 degrees
    • EF: Permafrost zone, below 0 degree

Pros of Koppen Classification

  1. Quantitative: easier to understand and measure
  2. Co-incides with vegetation pattern
  3. gave importance to effective precipitation (evapotranspiration)

Cons of Koppen Classification

  1. Difficult to memorize (not anymore 🙂 )
  2. Too much emphasis on average values
  3. Ignored precipitation intensity, cloud cover, daily temperature variations, number of rainy days etc.
  4. Ignored role of air masses
  5. Was not a genetic classification

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s