type B climate

Also known as: dry climate

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July 14, 2026

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In the Köppen climate classification system, Type B climates are defined by dryness rather than temperature. These arid and semiarid climates cover about a quarter of Earth's land surface, primarily between 15° and 30° latitude in both hemispheres. They are characterized by low precipitation, significant year-to-year variability in rainfall, high evaporation rates, and intense solar radiation. Type B climates are further divided into arid (BW) and semiarid (BS) subtypes. These can be further specified as warm (h) or cold (k), indicating temperature conditions. For example, the tropical and subtropical steppe climate is denoted as BSh, while the mid-latitude steppe is BSk.123

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Köppen climate classification
Type B climates
Arid and semiarid climates cover about a quarter of Earth’s land surface, mostly between 50° N and 50° S, but they are mainly found in the 15–30° latitude belt in both hemispheres. They exhibit low precipitation, great variability in precipitation from year…
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Arid and semiarid climates cover about a quarter of Earth’s land surface, mostly between 50° N and 50° S, but they are mainly found in the 15–30° latitude belt in both hemispheres. They exhibit low precipitation, great variability in precipitation from year…
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climate classification
Empirical classifications
Type B designates climates in which the controlling factor on vegetation is dryness (rather than coldness). Aridity is not a matter of precipitation alone but is defined by the relationship between the precipitation input to the soil in which the plants grow and the evaporative…
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Type B designates climates in which the controlling factor on vegetation is dryness (rather than coldness). Aridity is not a matter of precipitation alone but is defined by the relationship between the precipitation input to the soil in which the plants grow and the evaporative…
Read More