up:: [[PDC-ADV - Permaculture Design for Climate Resilience]] tags:: #source/course #on/permaculture #on/climate_change people:: [[Andrew Millison]] # PDC-ADV M2 - Climate Classification Systems [Climate Classification Systems – Permaculture Design: Tools for Climate Resilience](https://open.oregonstate.education/permaculturedesign/chapter/climate-classification-systems/) The [[Koppen-Geiger]] climate classification system, developed in 1884 by Wladimir Koppen and later revised by Rudolph Geiger in 1961, is a widely used tool for categorizing climate zones based on *temperature, precipitation, and the seasonality* of the [[Precipitation]]. It divides Earth's climate into *five major types (A, B, C, D, E) primarily defined by temperature*, except for B, which is defined by precipitation. The second and third letters in the code represent precipitation seasonality and heat levels, respectively. However, the system's limitations are evident in cases like the [[Temperate Mediterranean Climate]], where locations with different characteristics fall under the same classification. The Koppen-Trewartha system, developed by Glenn Thomas Trewartha, emerged as an improvement in 1966 and 1980, offering more defined climate zones, especially in mid-latitudes. Trewartha's system categorizes climate into six types (A-F) based on temperature or precipitation, providing more detailed distinctions. *Trewartha's maps are considered more reflective of ecosystem variations, but Koppen-Geiger remains more widespread in usage*. The [[Thornthwaite Climate Classification System]], devised by climatologist Charles Warren Thornthwaite in the 1930s and 1940s, it deals more with moisture and uses a mathematical equation considering *precipitation, evaporation, and water demands by plants*. Thornthwaite's map, less commonly used, shows distinctions in the Eastern half of the U.S., following elevation changes and the Appalachian Mountain chain. **Koppen-Geiger Climate Classification System:** - Developed in 1884 by Wladimir Koppen, later revised by Rudolph Geiger in 1961. - Widely used for categorizing climate zones based on temperature and precipitation. - Divides Earth's climate into five major types (A, B, C, D, E). - Second letter represents precipitation seasonality; third letter represents heat levels. **Koppen-Trewartha Climate Classification System:** - Developed by Glenn Thomas Trewartha, improving on Koppen-Geiger. - Six climate types (A-F) based on temperature or precipitation. - Provides more detailed distinctions, especially in mid-latitudes. - Trewartha's maps are reflective of ecosystem variations. **Thornthwaite Climate Classification System:** - Devised by Charles Warren Thornthwaite in the 1930s and 1940s. - Uses a mathematical equation based on precipitation, evaporation, and water demands by plants. - Less commonly used, distinguishes Eastern half of the U.S. based on elevation changes. Climate classification maps are general and should be complemented by site-specific factors. Recognizing the limitations of each system is crucial for a detailed understanding of climate conditions. #### Resources * [Climate Classification Systems – Permaculture Design: Tools for Climate Resilience](https://open.oregonstate.education/permaculturedesign/chapter/climate-classification-systems/) * [Collection of detailed Koppen Geiger maps from around the world](https://commons.wikimedia.org/wiki/User:Redtitan#K%C3%B6ppen_climate_maps_of_the_United_States,_states)