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How are Af, Am, and Aw tropical climates distinguished by rainfall patterns?
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Climate
Even in our warming world, there will be some chilly evenings.
In the Köppen climate classification, tropical climates (Type A) are distinguished primarily by their annual rainfall totals and the presence or duration of a dry season.1
- Wet equatorial climate (Af): These regions experience profuse, year-round precipitation with no distinct dry season. Rainfall is typically heavy, often ranging from 150 to 1,000 cm annually, and is driven by the consistent influence of the intertropical convergence zone or onshore trade winds.2
- Tropical monsoon and trade-wind littoral climate (Am): These climates are characterized by high annual rainfall totals—often exceeding those of Af climates—but they are distinguished by a short, distinct dry season, usually occurring during the low-sun ("winter") period.3
- Tropical wet-dry climate (Aw): These regions have the lowest annual rainfall of the three types (50–175 cm) and are defined by a pronounced seasonal cycle. They feature a distinct wet season and a longer dry season that becomes progressively more extended as one moves away from the Equator.4
Would you like to know more about how these rainfall patterns influence the specific vegetation found in these regions?