Index of aridity

From Glossary of Meteorology



index of aridity

A measure of the precipitation effectiveness or aridity of a region, proposed by De Martonne (1925), given by the following relationship:
ams2001glos-Ie4
where P (cm) is the annual precipitation and T (°C) the annual mean temperature.

De Martonne, E. 1925. Traité de Géographie Physique. Paris.


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