Semi-arid climate
A semi-arid climate, semi-desert climate, or steppe climate is a dry climate sub-type. It is located on regions that receive precipitation below potential evapotranspiration, but not as low as a desert climate. There are different kinds of semi-arid climates, depending on variables such as temperature, and they give rise to different biomes.
A more precise definition is given by the Köppen climate classification, which treats steppe climates (BSh and BSk) as intermediates between desert climates (BW) and humid climates (A, C, D) in ecological characteristics and agricultural potential. Semi-arid climates tend to support short, thorny or scrubby vegetation and are usually dominated by either grasses or shrubs as they usually cannot support forests.
To determine if a location has a semi-arid climate, the precipitation threshold must first be determined. The method used to find the precipitation threshold (in millimeters):
If the area's annual precipitation in millimeters is less than the threshold but more than half or 50% the threshold, it is classified as a BS (steppe, semi-desert, or semi-arid climate).[1]
Furthermore, to delineate hot semi-arid climates from cold semi-arid climates, a mean annual temperature of 18 °C (64.4 °F) is used as an isotherm. A location with a BS-type climate is classified as hot semi-arid (BSh) if its mean temperature is above this isotherm, and cold semi-arid (BSk) if not.