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What does the m stand for in the Am 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 "m" in the "Am" tropical climate code stands for monsoon.1
This classification refers to the tropical monsoon and trade-wind littoral climate, which is characterized by high temperatures, small annual temperature ranges, and plentiful annual precipitation. Unlike the "Af" (wet equatorial) climate, the "Am" climate experiences a short dry season. In many regions, such as southern and southeastern Asia, this climate is driven by the monsoon circulation, where seasonal shifts in wind patterns bring heavy precipitation during the summer and a drier period during the winter.1