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What does the f stand for in the Af tropical climate code?
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Köppen climate classification
The major climatic types are based on patterns of average precipitation, average temperature, and natural vegetation. This map depicts the world distribution of climate types based on the classification originally invented by Wladimir Köppen in 1900.
In the Köppen climate classification system, the letter "f" in the "Af" tropical climate code stands for "no dry season." This designation indicates that the region receives significant precipitation throughout the year, with the driest month recording at least 60 mm of rainfall.1
The "Af" climate, also known as a wet equatorial climate, is characterized by consistently high temperatures and plentiful precipitation, with very little annual temperature variation.2