View source for Tropical climate

{{Short description|Major climate group in Köppen classification}}
[[File:Koppen-Geiger_Map_v2_A_1991–2020.svg|thumb|upright=1.6|Locations where tropical climates occur, with subtypes listed, abbreviations in the [[Köppen climate classification]] in parentheses, and the [[equator]] highlighted:
{{legend|#0000FE|[[Tropical rainforest climate]] ('''Af'''),}}
{{legend|#0077FF|[[Tropical monsoon climate]] ('''Am'''),}}
{{legend|#46A9FA|[[Tropical savanna climate]] (Dry summer: '''As''', dry winter: '''Aw''').}}]]

'''Tropical climate''' is the first of the five major climate groups in the [[Köppen climate classification]] identified with the letter '''A'''. Tropical climates are defined by a monthly average temperature of {{convert|18|°C|°F|abbr=on}} or higher in the coolest month, featuring hot temperatures and high humidity all year-round. Annual precipitation is often abundant in tropical climates, and shows a seasonal rhythm but may have seasonal dryness to varying degrees. There are normally only two seasons in tropical climates, a wet (rainy/[[monsoon]]) season and a dry season. The annual temperature range in tropical climates is normally very small. Sunlight is intense in these climates.

There are three basic types of tropical climates within the tropical climate group: [[tropical rainforest climate]] ('''Af'''), [[tropical monsoon climate]] ('''Am''') and [[Tropical savanna climate|tropical savanna or tropical wet and dry climate]] ('''Aw''' for dry winters, and '''As''' for dry summers), which are classified and distinguished by the precipitation levels of the driest month in those regions.<ref>{{Cite web |date=2011-01-21 |title=tropics |url=http://www.nationalgeographic.org/encyclopedia/tropics/ |access-date=2022-04-26 |website=National Geographic Society |language=en}}</ref>

== Köppen climate classification ==
The [[Köppen climate classification]] is the most widely used climate classification system.<ref>{{cite web | url=https://bigladdersoftware.com/epx/docs/9-4/auxiliary-programs/k-ppen-climate-classification.html#:~:text=The%20modified%20K%C3%B6ppen%20Climate%20Classification,averages%20of%20temperature%20and%20precipitation | title=Köppen Climate Classification: Auxiliary Programs — EnergyPlus 9.4 }}</ref> It defines a tropical climate as a region where the mean temperature of the coldest month is greater than or equal to {{convert|18|°C|°F|abbr=on}} and does not fit into the criteria for B-group climates, classifying them as an A-group (tropical climate group).<ref name=":0">{{Cite journal|last1=Kottek|first1=Markus|last2=Grieser|first2=Jürgen|last3=Beck|first3=Christoph|last4=Rudolf|first4=Bruno|last5=Rubel|first5=Franz|date=2006-07-10|title=World Map of the Köppen-Geiger climate classification updated|journal=Meteorologische Zeitschrift|volume=15|issue=3|pages=259–263|doi=10.1127/0941-2948/2006/0130|bibcode=2006MetZe..15..259K|issn=0941-2948|url=https://opus.bibliothek.uni-augsburg.de/opus4/frontdoor/index/index/docId/40083 |bibcode-access=free |doi-access=free |url-status=live |archive-url=https://web.archive.org/web/20240124111757/https://opus.bibliothek.uni-augsburg.de/opus4/frontdoor/index/index/docId/40083 |archive-date= Jan 24, 2024 }}</ref> A-group regions are usually found in the [[tropics]], below 23.5 latitude in both the southern and northern hemisphere; they include areas around the Equator, Central America, North-central portions of South America, central Africa, southern portions of Asia and parts of North Australia and the Pacific Ocean islands.<ref>{{Cite web|url=http://koeppen-geiger.vu-wien.ac.at|title=World maps of Köppen-Geiger climate classification |website=koeppen-geiger.vu-wien.ac.at |url-status=dead |archive-url= https://web.archive.org/web/20240208021903/http://koeppen-geiger.vu-wien.ac.at/ |archive-date= Feb 8, 2024 }}</ref>

In Group A, there are three types of this climate: the [[Tropical rainforest climate|tropical rainforest climate (Af)]], [[Tropical monsoon climate|tropical monsoon climate (Am)]] and [[Tropical savanna climate|tropical wet and dry or savanna climate (Aw or As)]]. All of the three climates are classified by their P<sub>dry</sub> (short for precipitation of the driest month). Tropical rainforest climate's P<sub>dry</sub> should be greater than or equal {{convert|60|mm|in|abbr=on}}. Tropical monsoon climate's P<sub>dry</sub> should be in the range from <math>(100 - \tfrac{mean\ annual\ precipitation\ in\ mm}{25})</math> to 60&nbsp;mm. Tropical wet and dry or savanna climate's P<sub>dry</sub> should be less than <math>(100 - \tfrac{mean\ annual\ precipitation\ in\ mm}{25})</math>.<ref name=":0" />
[[File:Koppen-Geiger_Map_v2_Af_1991–2020.svg|alt=Tropical rainforest climate Region|left|thumb|upright=1.2|Tropical rainforest climate region]]{{Inline block|[[File:Koppen-Geiger_Map_v2_Am_1991–2020.svg|left|thumb|upright=1.2|Tropical monsoon climate region]]}}{{Inline block|[[File:Koppen-Geiger_Map_v2_Aw_1991–2020.svg|left|thumb|upright=1.2|Tropical savanna climate]]}}

== Tropical climate biome ==
[[File:Tamshiyacu Tahuayo Regional Conservation Area Iquitos Amazon Rainforest Peru.jpg|upright=1.25|thumb|Amazon rainforest near Iquitos, Perú.]]
Tropical climates normally have only two seasons, a wet season and a dry season. Depending on the location of the region, the wet and dry seasons can have varying duration. Annual temperature changes in the tropics are small. Due to the high temperatures and abundant rainfall, much of the plant life grows throughout the year. High temperature and humidity is the most suitable environment for [[epiphyte]]s to grow.<ref>{{Cite web |title=epiphyte {{!}} Definition, Adaptations, Examples, & Facts |url=https://www.britannica.com/plant/epiphyte |access-date=2022-04-26 |website=Britannica |language=en}}</ref> In many tropical climates, vegetation grows in layers: [[shrub]]s under tall trees, bushes under shrubs and [[grasses]] under bushes. Tropical plants are rich in resources, including coffee, cocoa and oil palm.<ref>{{Cite web|url=https://www.blueplanetbiomes.org/rainforest.php|title= Rainforest Biome|website=Blue Planet Biomes |first1=Michael |last1=G. |date=2001 |access-date=2020-04-03}}</ref><ref>{{Cite web|url=https://www.blueplanetbiomes.org/savanna.php|title= Savanna Biome|website=Blue Planet Biomes |access-date=2020-04-03}}</ref> Listed below are the types of vegetation unique to each of the three climates that make up the tropical climate biome.

=== Natural vegetation ===
Tropical rainforest vegetation including: [[Bengal bamboo]], [[bougainvillea]], [[curare]], [[Coconut|coconut tree]], [[durian]] and [[banana]].

Tropical monsoon vegetation including: [[teak]], [[Deodar cedar|deodar]], [[rosewood]], [[sandalwood]] and [[bamboo]].

Tropical wet and dry or savanna vegetation including: [[Senegalia senegal|acacia senegal]], [[Cenchrus purpureus|elephant grass]], [[Eucalyptus marginata|jarrah tree]], [[Eucalyptus|gum tree eucalyptus]] and [[Vachellia drepanolobium|whistling thorn]].

{{Climate chart|[[Biak|Biak, Indonesia]]|31=180|24=29|25=240|26=25|27=29|28=220|29=25|30=29|32=25|22=250|33=30|34=190|35=25|36=29|37=230|clear=none|float=right|23=25|21=28|25|10=250|29|250|25|28|240|25|29|11=25|20=25|12=29|13=200|14=25|15=29|16=250|17=25|18=29|19=230|source=<ref>{{cite web | url=http://www.weatherbase.com/weather/weather.php3?s=6579&refer=&units=metric | title=Biak, Indonesia Travel Weather Averages (Weatherbase) }}</ref>}}

== Tropical rainforest climate ==
The Köppen classification identifies [[tropical rainforest climate]]s (Zone Af: f = "feucht", German for moist) as usually having north and south latitudinal ranges of just 5-10 degrees from the equator.<ref>{{Cite web|url=http://www.nationalgeographic.org/encyclopedia/koppen-climate-classification-system/|title=Köppen Climate Classification System|date=2019-10-24|website=National Geographic Society|language=en|access-date=2020-04-02}}</ref><ref name=":1">{{Cite book|last1=McKnight|first1=Tom L. (Tom Lee)|url=http://archive.org/details/physicalgeographmckn|title=Physical geography : a landscape appreciation|last2=Hess|first2=Darrel|date=2000|publisher=Upper Saddle River, N.J. : Prentice Hall|others=Internet Archive}}</ref> Tropical rainforest climates have high temperatures: the yearly average temperature is normally between {{convert|21|and|30|C|F}}.<ref name=":2">{{Cite web|url=https://php.radford.edu/~swoodwar/biomes/?page_id=100|title=Tropical Rainforest {{!}} Biomes of the World|language=en-US|access-date=2020-04-02}}</ref><ref name=":3">{{Cite web|url=https://www.thesustainabilitycouncil.org/tropical-rainforest-biome.html|title=Tropical Rainforest Biome - Tropical Moist Climates (Af) {{!}} The Tropical Climate {{!}} The Köppen Climate Classification System {{!}} Resources|website=ISC-Audubon|language=en-gb|access-date=2020-04-02}}</ref> The precipitation can reach over 100 inches a year.<ref name=":2" /><ref name=":3" /> The seasons are evenly distributed throughout the year, and there is almost no drought period here.<ref name=":1" /> Regions that contain tropical rainforest climate mainly include the upper Amazon basin of South America, the Northern Zaire (Congo) basin of Africa, and the islands of the East Indies.<ref name=":1" />

The tropical rainforest climate differs from other subtypes of tropical climates as it has more kinds of trees due to its [[precipitation]].<ref name=":3" /> The large number of trees contribute back to the [[humidity]] of the climate because of the transpiration, which is the process of water [[Evaporation|evaporated]] from the surface of living plants to the atmosphere. The warmth and abundant precipitation heavily contributes to the diversity and characteristics of vegetations under the tropical rainforest climate.<ref name=":2" /> The vegetations develop a vertical stratification and various growth forms to receive enough sunlight, which is unusual under other types of climate.<ref name=":2" />

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== Tropical monsoon climate ==
{{Climate chart|[[Miami]]|31=143.3|24=31.7|25=192.5|26=24.4|27=31.0|28=193.8|29=22.3|30=29.2|32=19.3|22=144.8|33=26.9|34=67.6|35=16.4|36=24.8|37=46.5|clear=none|float=right|23=24.8|21=31.7|15.1|10=60.7|24.0|51.1|15.8|24.7|52.8|17.9|26.2|11=19.9|20=24.6|12=28.0|13=72.4|14=22.3|15=29.6|16=157.7|17=23.9|18=30.9|19=237.0|source=[https://worldweather.wmo.int/en/city.html?cityId=267]}}
The Köppen classification tool identifies tropical monsoon climate as having small annual temperature ranges, high temperatures, and plentiful precipitation. This climate also has a short dry season which almost always occurs in the winter.<ref>{{Cite web|url=https://www.britannica.com/science/tropical-monsoon-and-trade-wind-littoral-climate|title=Tropical monsoon and trade-wind littoral climate {{!}} meteorology|website=Encyclopedia Britannica|language=en|access-date=2020-04-03}}</ref> The tropical monsoon climate is often found within countries in the south and southeast Asia region between the latitude of 10 degrees north and the Tropic of Cancer. It can also be found in West Africa and South America. The annual temperature of regions under tropical monsoon climate is also stable.

The [[tropical monsoon climate]] has the following main characteristic. The average annual temperature is around {{convert|27.05|°C}} and has an average annual temperature range of about {{convert|3.6|C-change|0|abbr=on}}.<ref name=":4">{{Cite web|url=https://www.earthonlinemedia.com/ebooks/tpe_3e/climate_systems/tropical_monsoon_1.html |title=Tropical Monsoon Climate |website=www.earthonlinemedia.com|access-date=2020-04-02}}</ref> Distinction between wet and drought seasons, the tropical monsoon climate is different from other tropical climates because of its uneven precipitation throughout the year.

There are three main seasons of tropical monsoon climate: the cool dry season is from fall to late winter, the hot dry season is in the spring and the rainy or [[monsoon]] season is near or during the summer months.<ref>{{Cite web|url=https://www.yourarticlelibrary.com/geography/climate-geography/seasons-of-tropical-monsoon-climate/77692|title=Seasons of Tropical Monsoon Climate|date=2016-03-08|website=Your Article Library|language=en-US|access-date=2020-04-02}}</ref>

The tropical monsoon forest mainly consists of three layered structures. The first layer is the surface layer which is a very dense layer of shrubs and grasses. The second layer is the [[Understory|understory layer]] with trees about 15 meters tall. The top layer is called the [[Canopy (biology)|canopy tree layer]] which has trees from 25 to 40 meters tall and those trees grow closely while above is the emergent layer with sporadic trees taller than 35 meters.<ref>{{Cite web |date=2015-01-23 |title=Rainforest layers |url=https://www.rainforestjournal.com/rainforest-layers/ |access-date=2022-04-26 |website=www.rainforestjournal.com |language=en-US}}</ref>

== Tropical savanna or wet and dry climate ==

[[Tropical savanna climate]]s, or tropical wet and dry climates, are mainly located between the 10° and 25° north-south latitudes, and often occur at the outer margins of the tropics. Typical regions include central Africa, parts of South America, as well as northern and eastern Australia.<ref>{{Cite web|url=https://www.worldatlas.com/articles/what-are-the-characteristics-of-a-tropical-savanna-type-of-climate.html|title=What Are The Characteristics Of A Tropical Savanna Type Of Climate?|website=WorldAtlas|date=22 January 2018 |language=en|access-date=2020-04-03}}</ref> The temperature range of savanna climate is between {{convert|20|and|30|C|F}}. In summer, the temperature is between 25&nbsp;°C and 30&nbsp;°C, while in winter the temperature is between 20&nbsp;°C and 30&nbsp;°C, but still stays above an 18&nbsp;°C mean.<ref>{{Cite web|url=https://www.blueplanetbiomes.org/savanna_climate.php|title=Blue Planet Biomes - Savanna Climate|website=www.blueplanetbiomes.org|access-date=2020-04-03}}</ref> The annual precipitation is between 700 and 1000&nbsp;mm. The driest months are generally in the winter and they have less than 60&nbsp;mm of rainfall (often much less).<ref>{{Cite web |title=The grassland biome |url=https://ucmp.berkeley.edu/exhibits/biomes/grasslands.php |access-date=2022-04-26 |website=ucmp.berkeley.edu}}</ref>

Regions under the savanna climate usually have lands covered with flat grassland vegetation with areas of woodlands. Those grassland biomes cover almost 20% of the Earth's surface.<ref>{{Cite web|url=https://www.conserve-energy-future.com/savanna-biome.php|title=Savanna Biome: Location, Climate, Temperature, Plants and Animals|date=2018-08-26|website=Conserve Energy Future|language=en-US|access-date=2020-04-03}}</ref> The grassland vegetation types include Rhodes grass, red oats grass, star grass and lemongrass.<ref>{{Cite web|url=https://kids.nceas.ucsb.edu/biomes/savanna.html|title=KDE Santa Barbara|website=kids.nceas.ucsb.edu|access-date=2020-04-03}}</ref>

==See also==
* [[Humid subtropical climate]]
* [[Megathermal]]
* [[Subtropics]]

== References ==
{{Reflist}}

{{Köppen}}
{{Seasons}}

{{Authority control}}

[[Category:Climate]]