[Answer] The Köppen climate classification recognizes ________ principal climate groups.

Answer: wet tropics

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The Köppen climate classification recognizes ________ principal climate groups. The Köppen climate classification scheme divides climates into five main climate groups: A (tropical) B (dry) C (temperate) D (continental) and E (polar). The second letter indicates the seasonal precipitation type while the third letter indicates the level of heat. Summers are defined as the 6-month period that is warmer either from April–September and/or October–March while winter is the 6-month period that is cooler. Group A: Tropical climates The Köppen climate classification scheme divides climates into five main climate groups: A (tropical) B (dry) C (temperate) D (continental) and E (polar). The second letter indicates the seasonal precipitation type while the third letter indicates the level of heat. Summers are defined as the 6-month period that is warmer either from April–September and/or October–March while winter is the 6-month period that is cooler. Group A: Tropical climates This type of climate has every month of the year with an average temperature of 18 °C (64.4 °F) or higher with significant precipitation. • Af = Tropical rainforest climate; average precipitation of at least 60 mm (2.4 in) in every month. • Am = Tropical monsoon climate; driest month (which nearly always occurs at or soon after the "winter" solstice for that side of the equator) with precipitation less than 60 mm (2.4 in) but at least ${\textstyle 100-\left({\frac {Total\ Annual\ Precipitation\ (mm)}{25}}\right)}$. • Aw or As = Tropical wet and dry or savanna climate; with the driest month having precipitation less than 60 mm (2.4 in) and less than ${\textstyle 100-\left({\frac {Total\ Annual\ Precipitation\ (mm)}{25}}\right)}$. Group B: Dry climates This type of climate is defined by little precipitation. The threshold in millimeters is determined by multiplying the average annual temperature in Celsius by 20 then adding: The Köppen climate cl...

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