Editing Subtropics (section)

== Definition ==
{{See also|List of locations with a subtropical climate}}

The tropics have been ''historically'' defined as lying between the [[Tropic of Cancer]] and [[Tropic of Capricorn]], at latitudes {{Circle of latitude|Tropical|Convert}} north and south, respectively.<ref>{{cite book|chapter-url=http://www.eolss.net/Sample-Chapters/C01/E4-03-04-03.pdf|title=Principal Weather Systems in Subtropical and Tropical Zones|author=I. G. Sitnikov|volume=1|chapter=1|publisher=[[Encyclopedia of Life Support Systems]]}}</ref> According to the American Meteorological Society, the poleward fringe of the subtropics is at latitudes approximately [[35th parallel north|35° north]] and [[35th parallel south|south]], respectively.<ref>{{cite web|access-date=24 March 2013|author=Glossary of Meteorology|date=25 April 2012|publisher=[[American Meteorological Society]]|title=Subtropics|url=http://glossary.ametsoc.org/wiki/Subtropics}}</ref>

[[File: East Battery Street Charleston Aug2010.jpg|thumb|Houses in subtropical Charleston, South Carolina, along [[The Battery (Charleston)|The Battery]]]]

Several methods have been used to define the subtropical climate depending on the climate system used.{{citation needed|date=June 2023}}

The most well known<ref>{{Cite web |last=Arise |first=Lotus |date=2021-01-27 |title=Trewartha Climatic Classification - UPSC (Climatology) |url=https://lotusarise.com/trewartha-climatic-classification-upsc/ |access-date=2022-03-26 |language=en-US}}</ref> is the [[Trewartha climate classification]], which defines a subtropical region as one that has at least eight months with a mean temperature greater than {{convert|10|°C|°F|1}} and at least one month with a mean temperature under {{convert|18|°C|°F|1}}.<ref>Belda et al. Climate classification revisited: from Köppen to Trewartha. In: Climate Research Vol. 59: 1–13, 2014.</ref>

German climatologists Carl Troll and Karlheinz Paffen defined ''warm temperate zones'' as plain and hilly lands having an average temperature of the coldest month between {{convert|2|°C|°F|1}} and {{convert|13|°C|°F|1}} in the [[Northern Hemisphere]] and between {{convert|6|°C|°F|1}} and {{convert|13|°C|°F|1}} in the [[Southern Hemisphere]], excluding [[oceanic climate|oceanic]] and [[continental climate]]s.  According to the Troll-Paffen climate classification, there generally exists one large subtropical zone named the warm-temperate subtropical zone,<ref>[http://web.tiscali.it/linnets/Troll-Paffen.jpg Climatic map by Istituto Geografico De Agostini, according to Troll-Paffen climate classification] {{webarchive|url=https://web.archive.org/web/20121004052732/http://web.tiscali.it/linnets/Troll-Paffen.jpg |date=4 October 2012 }}</ref> which is subdivided into seven smaller areas.<ref>[http://www.klimadiagramme.de/Frame/troll.html Die Klimaklassifikation nach Troll / Paffen] – klimadiagramme.de</ref>

According to the E. Neef climate classification, the subtropical zone is divided into two parts: ''rainy winters of the west sides'' and ''eastern subtropical climate''.<ref>[http://www.klimadiagramme.de/Frame/neef.html Die Klimaklassifikation nach E. Neef] – klimadiagramme.de</ref>  According to the Wilhelm Lauer & Peter Frankenberg climate classification, the subtropical zone is divided into three parts: ''high-continental'', ''continental'', and ''maritime''.<ref>[http://www.manuel-friedrich.de/ab/GEO033.pdf Wilhelm Lauer & Peter Frankenberg climate classification]</ref>  According to the Siegmund/Frankenberg climate classification, subtropical is one of six climate zones in the world.<ref>[http://www.ph-heidelberg.de/geographie/forschung-und-entwicklung/klimakarte-der-erde.html ''Die Klimatypen der Erde''] – Pädagogische Hochschule in [[Heidelberg]]</ref>

[[Leslie Holdridge]] defined the subtropical climates as having a mean annual [[biotemperature]] between the frost line or critical temperature line, 16&nbsp;°C to 18&nbsp;°C (depending on locations in the world), and 24&nbsp;°C.<ref>[http://reddcr.go.cr/sites/default/files/centro-de-documentacion/holdridge_1966_-_life_zone_ecology.pdf ''LIFE ZONE ECOLOGY by L. R. Holdridge'']</ref> The frost line separates the warm temperate region from the subtropical region. It represents the dividing line between two major physiological groups of evolved plants. Most of the plants are sensitive to low temperatures on the warmer side of the line. They can be killed back by frosts as they have not evolved to withstand periods of cold. On the colder temperate side of the line, the total flora is adapted to survive periods of variable lengths of low temperatures, whether as seeds in the case of the annuals or as perennial plants that can withstand the cold. The 16&nbsp;°C–18&nbsp;°C segment is often "simplified" as 17&nbsp;°C <math display="inline">\bigl(2^{(\log_{2}12\ +\ 0.5)}\ ^\circ\! \mathrm{C} \approx16.97\ ^\circ\! \mathrm{C}\bigr)</math>.<ref>[https://www.researchgate.net/figure/The-original-life-zone-chart-of-Holdridge-4_fig2_264499178 ''The climate of Carpathian Region in the 20th century based on the original and modified Holdridge life zone system'']</ref>

The Holdridge subtropical climates straddle more or less the warmest subtropical climates and the less warm tropical climates as defined by the Köppen-Geiger or Trewartha climate classifications.{{citation needed|date=June 2023}}

However, [[Wladimir Köppen]] has distinguished the hot or subtropical and tropical (semi-)arid climates (''BWh'' or ''BSh'') having an average annual temperature greater than or equal to {{convert|18|°C|°F|1}} from the cold or temperate (semi-)arid climates (''BWk'' or ''BSk'') whose annual temperature average is lower.<ref>{{Cite web | url=https://www.worldatlas.com/articles/what-is-a-desert-climate.html |title = What is a Desert Climate?| date=November 2017 }}</ref> This definition, though restricted to dry regions, is almost similar to Holdridge's.