Cold cap

From Glossary of Meteorology



cold cap

As defined by A. Supan (1879), a region of the earth within which the mean temperature of the warmest month is less than 10°C. This limiting condition closely approximates the temperature at the arctic tree line, and was later adopted by W. Köppen (1918) as his boundary between the polar climates and tree climates.

Supan also defined temperate belt and hot belt in his early form of climatic classification.

Supan, A. 1879. Die Temperaturzonen der Erde. Petermanns Geog. Mitt.. 25. 349–358.

Köppen, W. P. 1918. Klassification der Klimate nach Temperatur, Niederschlag und Jahreslauf. Petermanns Geog. Mitt.. 64. 193–203; 243–248.


Copyright 2022 American Meteorological Society (AMS). For permission to reuse any portion of this work, please contact permissions@ametsoc.org. Any use of material in this work that is determined to be “fair use” under Section 107 of the U.S. Copyright Act (17 U.S. Code § 107) or that satisfies the conditions specified in Section 108 of the U.S.Copyright Act (17 USC § 108) does not require AMS’s permission. Republication, systematic reproduction, posting in electronic form, such as on a website or in a searchable database, or other uses of this material, except as exempted by the above statement, require written permission or a license from AMS. Additional details are provided in the AMS Copyright Policy statement.