Köppen Climate Classification A. Beckingham Geography 12

Who, why Wladimir Köppen, 1846-1940 Climatologist, meteorologist, botanist Connection between climate and vegetation Developed a climate classification system that uses avg. temp.,avg. precip., and the seasonality of precip. The system is based on the concept that vegetation is the best expression of climate. Rainforest Shrub land

Köppen Classification 5 main groups Tropical Dry Temperate Continental Polar

Köppen Classification A – Tropical rainy climates Avg. Temp. > 18°C every month Annual precip. is large and exceeds evaporation No winter season

Köppen Classification B – Dry climates Evaporation exceeds precipitation for the year No water surplus No permanent streams would orginate in a B climate zone

Köppen Classification C – Temperate (mild) climates Coldest month avg. temp. < 18°C and > -3°C At least one month avg. temp. > 10°C Distinct summer and winter seasons

Köppen Classification D – Continental (snowy-forest) climates Coldest month avg. temp. < -3°C Warmest month avg. temp. > 10°C (forest is not generally found where the warmest month is colder than 10°C)

Köppen Classification E – Polar climates Warmest month avg. temp. < 10°C No summer season

Köppen Classification H – Highland climates Influenced by high elevation rather than high latitude Variable with conditions chaning over relatively small distances Occur at all latitudes; coastal and interior No subdivisions

Köppen Classification Subdivisions: B group BS – Steppe climate 400-800mm precip. annually BW – Desert climate < 400mm precip. annually Timing of the precip. is significant due to evaporation If precip. is concentrated in the low-sun season then less precip. is required to designate a steppe climate zone

Köppen Classification Subdivisions: A, C, and D groups Second letter f – moist, adequate precip. in all months, no dry season w – dry season in the winter (low-sun season) s – dry season in the summer (high-sun season) m – rainforest climate, despite short dry season (A Group only)

Köppen Classification Subdivisions: E group ET – Tundra climate Warmest month temp. > 0°C but <10°C EF – Ice cap climate Warmest month temp. < 0°C

Köppen Classification Subdivisions: Third letter (B, C, and D groups) a – warmest month > 22°C (hot summer) b – warmest month < 22°C, 4 months > 10°C (warm summer) c – fewer than 4 months > 10°C (cool summer) d – same as C but coldest month < -38°C (cold summer) h – dry and hot; mean annual temp. >18°C (low-lat. desert) k – dry and cold; mean annual temp. <18°C (mid-lat. desert)