Ajay Kumar: Created a new article

2023-08-29T05:43:44Z

Created a new article

New page

{{short description|Climate with precipitation below potential evapotranspiration}}
[[File:BS climate.png|thumb|upright=1.75|Regions with semi-arid climates
{{legend|#F5A301|[[#Hot semi-arid climates|BSh]]}}
{{legend|#FFDB63|[[#Cold semi-arid climates|BSk]]}}]]
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 [[Evapotranspiration#Potential evapotranspiration|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 [[biome]]s.

==Defining attributes of semi-arid climates==
A more precise definition is given by the [[Köppen climate classification]], which treats [[steppe]] climates (''BSk'' and ''BSh'') as intermediates between [[desert climate]]s (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 [[grass]]es or [[shrub]]s as they usually cannot support forests.
[[File:Les Falaises de Bandiagara.jpg|thumb|[[Sahel]] region of [[Mali]]]]

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):
*multiply by 20 the average annual temperature in degrees Celsius and then
**add 280 if at least 70% of the total precipitation falls in the summer half of the year (April–September in the northern hemisphere, October–March in the southern hemisphere)
**add 140 if 30–70% of the total precipitation falls in the summer half of the year
**add nothing if less than 30% of the total precipitation falls in the summer half of the year

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 or semi-arid climate).<ref name="Hydrology and Earth System Sciences">{{cite web|last1=Peel|first1=M. C.|last2=Finlayson|first2=B. L.|last3=McMahon|first3=T. A.|title=Updated world map of the Koppen-Geiger climate classification|url=http://www.hydrol-earth-syst-sci.net/11/1633/2007/hess-11-1633-2007.pdf|website=hydrol-earth-syst-sci.net|publisher=Hydrology and Earth System Sciences|access-date=May 8, 2017|location=University of Melbourne|pages=1633–1644|date=March 1, 2007}}</ref>

Furthermore, to delineate hot semi-arid climates from cold semi-arid climates, a mean annual temperature of {{cvt|18|C|1}} 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.

==Hot semi-arid climates==
{{Redirect|BSh||BSH (disambiguation){{!}}BSH}}
[[File:Koppen-Geiger Map BSh present.svg|thumb|upright=1.7|Regions with hot semi-arid climates]]

Hot semi-arid climates (type "BSh") tend to be located in the 20s and 30s latitudes of the [[tropics]] and [[subtropics]], typically in proximity to regions with a [[tropical savanna climate|tropical savanna]], [[Mediterranean climate|Mediterranean]], and [[Hot desert climate|hot desert]] climates. These climates tend to have hot, or sometimes extremely hot, summers and warm to cool winters, with some to minimal precipitation. Hot semi-arid climates are most commonly found around the fringes of subtropical deserts.

Hot semi-arid climates are most commonly found in [[Africa]], [[Australia]], and [[South Asia]]. In Australia, a large portion of the [[Outback]] surrounding the central desert regions lies within the hot semi-arid climate region.<ref>[http://www.bom.gov.au/cgi-bin/climate/cgi_bin_scripts/clim_classification.cgi Bureau of Meteorology – climate classification maps]{{dead link|date=November 2016 |bot=InternetArchiveBot |fix-attempted=yes }}</ref>{{Clarify|date=September 2013}} In South Asia, both [[India]] and parts of [[Pakistan]] experience the seasonal effects of [[monsoon]]s and feature short but well-defined [[wet season]]s, but are not sufficiently wet overall to qualify as either a [[tropical savanna climate|tropical savanna]] or a [[humid subtropical climate|humid subtropical]] climate.

Hot semi-arid climates can be also found in parts of [[North America]], such as most of northern [[Mexico]], the [[ABC islands (Leeward Antilles)|ABC Islands]], the [[rain shadow]]s of [[Hispaniola]]'s mountain ranges in the [[Dominican Republic]] and [[Haiti]], parts of the [[Southwestern United States]], and sections of [[South America]] such as the ''[[sertão]]'', the [[Gran Chaco]], and the poleward side of the arid deserts, where they typically feature a [[Mediterranean climate|Mediterranean]] precipitation pattern, with generally rainless summers and wetter winters. They are also found in few areas of [[Europe]] surrounding the [[Mediterranean Basin]]. In Europe, BSh climates are primarily found in southeastern [[Spain]],<ref name=" GOBIERNO DE ESPAÑA">{{cite web|title=ATLAS CLIMÁTICO IBÉRICO|url=http://www.aemet.es/documentos/es/conocermas/recursos_en_linea/publicaciones_y_estudios/publicaciones/Atlas-climatologico/Atlas.pdf|website=administracion.gob.es/|publisher=Instituto de Meteorologia de Portugal|access-date=May 8, 2017}}</ref><ref name=spainclimate>{{Cite journal |date=2012 |title=Climate Atlas of the Archipelagos of the Canary Islands, Madeira and the Azores |url=https://www.aemet.es/documentos/es/conocermas/recursos_en_linea/publicaciones_y_estudios/publicaciones/2Atlas_climatologico/Atlas_Clima_Macaronesia___Baja.pdf |website=aemet.es |doi=10.31978/281-12-006-X|hdl=20.500.11765/398 }}</ref> various parts of south [[Greece]],<ref name="Climate Atlas of Greece (Hellenic National Meteorological Service)">{{cite web | url=http://www.hnms.gr:80/hnms/greek/pdf/Climate_Atlas_Of_Greece.pdf | archive-url=https://web.archive.org/web/20170921184739/http://www.hnms.gr:80/hnms/greek/pdf/Climate_Atlas_Of_Greece.pdf | url-status=dead | archive-date=21 September 2017 | title=Climate Atlas of Greece | publisher=Hellenic National Meteorological Service | access-date=30 December 2019}}</ref> <ref name="Monthly Bulletins">{{cite web | url=https://www.meteo.gr/Monthly_Bulletins.cfm | title=Monthly Bulletins | publisher=[[National Observatory of Athens]] | accessdate=9 April 2023}}</ref> and marginal areas of [[Portugal]] and [[Cyprus]].

==Cold semi-arid climates==
{{Redirect|BSk||BSK (disambiguation){{!}}BSK}}
[[File:Koppen-Geiger Map BSk present.svg|thumb|upright=1.7|Regions with cold semi-arid climates]]

Cold semi-arid climates (type "BSk") tend to be located in elevated portions of [[temperate zones]], typically bordering a [[humid continental climate]] or a [[Mediterranean climate]]. They are also typically found in continental interiors some distance from large bodies of water. Cold semi-arid climates usually feature warm to hot dry summers, though their summers are typically not quite as hot as those of hot semi-arid climates. Unlike hot semi-arid climates, areas with cold semi-arid climates tend to have cold and possibly freezing winters. These areas usually see some [[snowfall]] during the winter, though snowfall is much lower than at locations at similar latitudes with more humid climates.

Areas featuring cold semi-arid climates tend to have higher elevations than areas with hot semi-arid climates, and tend to feature major temperature swings between day and night, sometimes by as much as 20 °C (36 °F) or more. These large [[diurnal temperature variation]]s are seldom seen in hot semi-arid climates. Cold semi-arid climates at higher latitudes tend to have dry winters and wetter summers, while cold semi-arid climates at lower latitudes tend to have precipitation patterns more akin to [[subtropical climate]]s, with dry summers, relatively wet winters, and even wetter springs and autumns.

Cold semi-arid climates are most commonly found in East Asia, the Middle East, including other parts of Asia, and Western North America. However, they can also be found in Northern Africa, South Africa, Europe (Central parts of Spain, Crimea, Greece, and North Macedonia), sections of South America and sections of interior southern Australia (e.g. [[Kalgoorlie]] and [[Mildura]]) and southern New Zealand ([[Alexandra, New Zealand|Alexandra]]).

==Charts of selected cities==
{{climate chart
|[[Patos]], [[Paraíba]], [[Brazil]]
|21.7|32|66
|21.7|31.7|139
|21.8|31.2|213
|21.7|30.1|177
|21.4|28.7|55
|20.6|27.4|28
|19.7|27|12
|19.5|27.6|3
|20.3|29.5|1
|20.8|31|4
|21.1|31.7|8
|21.4|32|22
|source=<ref>[http://www.inmet.gov.br/projetos/rede/pesquisa/gera_serie_txt_mensal.php?&mRelEstacao=82791&btnProcesso=serie&mRelDtInicio=01/01/1961&mRelDtFim=31/12/2013&mAtributos=,,,,,,,,,1,,,,,,, Climate of Patos] Access on January 16th, 2016.</ref>
|float=left
}}
{{climate chart
|[[Kalgoorlie]], [[Australia]]
|18.3|33.6|27.2
|17.9|32.1|32.4
|16.1|29.5|25.0
|12.8|25.3|20.0
|8.7|20.7|24.8
|6.3|17.6|27.1
|5.1|16.8|24.2
|5.7|18.7|21.2
|8.1|22.4|13.5
|11.3|26.0|15.7
|14.2|29.1|18.9
|16.7|32.1|16.3
|source=<ref>[http://www.bom.gov.au/climate/averages/tables/cw_012038_All.shtml] Access on August 14, 2021.</ref>
|float=left
|clear=none
}}
{{climate chart
|[[Jaipur]] (Sanganer), [[India]]
|4|19|8
|7|22|12
|12|29|6
|17|34|4
|21|38|16
|23|38|66
|22|31|216
|20|29|231
|19|30|80
|15|30|23
|9|25|3
|5|20|3
|source=[https://web.archive.org/web/20110721162913/http://www.mausam.gov.in/WEBIMD/ClimatologicalAction.do?function=getStationDetails&actionParam=1&param=2&station=Jaipur(Sanganer) India Weather On Web]
|float=left
|clear=none
}}
{{climate chart
|[[Niamey]], [[Niger]]
|16.1|32.5|0
|19.0|35.7|0
|22.9|39.1|3.9
|26.5|40.9|5.7
|27.7|40.2|34.7
|25.7|37.2|68.8
|24.1|34.0|154.3
|23.2|33.0|170.8
|23.6|34.4|92.2
|24.2|37.8|9.7
|19.5|36.2|0.7
|16.7|33.3|0
| source = [[Deutscher Wetterdienst]]<ref>
{{cite web
| url = http://www.dwd.de/DWD/klima/beratung/ak/ak_610520_kt.pdf
| title = Klimatafel von Niamey (Aéro) / Niger
| publisher = Federal Ministry of Transport and Digital Infrastructure
| access-date = 14 June 2016}}
</ref>
|float=left
|clear=none
}}
{{climate chart
|[[Murcia]], [[Spain]]
|4.7|16.6|25
|5.9|18.4|28
|7.7|20.9|30
|9.7|23.3|27
|13.3|26.6|32
|17.4|31.0|20
|20.3|34.0|5
|20.9|34.2|10
|18.0|30.4|27
|13.9|25.6|44
|8.9|20.3|32
|5.8|17.2|21
|source = [[Agencia Estatal de Meteorología]]<ref>{{cite web
|url=http://www.aemet.es/es/elclima/datosclimatologicos/valoresclimatologicos?l=7228&k=mur
|title=Valores Climatológicos Normales. Murcia - Alcantarilla
|publisher=Aemet.es
|access-date=2013-09-08
|url-status=dead
|archive-url=https://web.archive.org/web/20091214172509/http://www.aemet.es/es/elclima/datosclimatologicos/valoresclimatologicos?l=7228&k=mur
|archive-date=2009-12-14
}}</ref>
|float=left
|clear=none
}}
{{climate chart
|[[Reno, Nevada]], [[United States]]
|-3.7|7.6|26.2
|-1.7|10.6|25.9
|0.8|14.4|19.3
|3.2|17.7|11.9
|7.5|23.1|12.4
|11.1|28.5|13
|14.3|33.4|4.6
|13.2|32.6|5.8
|9.2|27.8|8.9
|3.8|20.7|13
|-0.8|12.8|20.8
|-3.9|7.6|26.2
| source = [[NOAA]]<ref>
{{cite web
| url = http://www.nws.noaa.gov/climate/xmacis.php?wfo=rev
| title = NowData – NOAA Online Weather Data
| publisher = [[National Oceanic and Atmospheric Administration]]
| access-date = June 6, 2015}}</ref>
|float=left
|clear=none
}}
{{clear}}

==See also==
* [[Continental climate]]
* [[Dry climate]]
* [[Desert climate]]
* [[Dust Bowl]] (an era of devastating dust storms, mostly in the 1930s, in semi-arid areas on the Great Plains of the United States and Prairies of Canada)
* [[Goyder's Line]] (a boundary marking the limit of semi-arid climates in the Australian state of South Australia)
* [[Köppen climate classification]]
* [[Palliser's Triangle]] (semi-arid area of Canada)
* [[Ustic|Ustic (Soil Moisture Regime)]]
* [[Wave height]]

==References==
{{reflist}}

==External links==

{{Koppen}}

[[Category:Grasslands]]
[[Category:Köppen climate types]]
[[Category:Plains]]
[[Category:Prairies]]

Semi-arid climate - Revision history

Ajay Kumar: Created a new article