The desert climate or arid climate (in the

Köppen climate classification The Köppen climate classification divides Earth climates into five main climate groups, with each group being divided based on patterns of seasonal precipitation and temperature. The five main groups are ''A'' (tropical), ''B'' (arid), ''C'' (te ...

''BWh'' and ''BWk'') is a

dry climate Aridity is the condition of geographical regions which make up approximately 43% of total global available land area, characterized by low annual precipitation, increased temperatures, and limited water availability.Perez-Aguilar, L. Y., Plata ...

sub-type in which there is a severe excess of

evaporation Evaporation is a type of vaporization that occurs on the Interface (chemistry), surface of a liquid as it changes into the gas phase. A high concentration of the evaporating substance in the surrounding gas significantly slows down evapora ...

over

precipitation In meteorology, precipitation is any product of the condensation of atmospheric water vapor that falls from clouds due to gravitational pull. The main forms of precipitation include drizzle, rain, rain and snow mixed ("sleet" in Commonwe ...

. The typically bald, rocky, or sandy surfaces in desert climates are dry and hold little moisture, quickly evaporating the already little rainfall they receive. Covering 14.2% of Earth's land area, hot deserts are the second-most common type of climate on Earth after the

Polar climate The polar climate regions are characterized by a lack of warm summers but with varying winters. Every month a polar climate has an average temperature of less than . Regions with a polar climate cover more than 20% of the Earth's area. Most of ...

. There are two variations of a

desert A desert is a landscape where little precipitation occurs and, consequently, living conditions create unique biomes and ecosystems. The lack of vegetation exposes the unprotected surface of the ground to denudation. About one-third of the la ...

climate according to the

: a hot desert climate (''BWh''), and a cold desert climate (''BWk''). To delineate "hot desert climates" from "cold desert climates", a mean annual temperature of is used as an isotherm so that a location with a ''BW'' type climate with the appropriate temperature above this isotherm is classified as "hot arid subtype" (''BWh''), and a location with the appropriate temperature below the isotherm is classified as "cold arid subtype" (''BWk''). Most desert/arid climates receive between of rainfall annually, although some of the most consistently hot areas of

Central Australia Central Australia, also sometimes referred to as the Red Centre, is an inexactly defined region associated with the geographic centre of Australia. In its narrowest sense it describes a region that is limited to the town of Alice Springs and ...

, the

Sahel The Sahel region (; ), or Sahelian acacia savanna, is a Biogeography, biogeographical region in Africa. It is the Ecotone, transition zone between the more humid Sudanian savannas to its south and the drier Sahara to the north. The Sahel has a ...

and Guajira Peninsula can be, due to extreme potential evapotranspiration, classed as arid with the annual rainfall as high as .

Precipitation

Although no part of Earth is known for certain to be rainless, in the

Atacama Desert The Atacama Desert () is a desert plateau located on the Pacific Ocean, Pacific coast of South America, in the north of Chile. Stretching over a strip of land west of the Andes Mountains, it covers an area of , which increases to if the barre ...

of northern Chile, the average annual rainfall over 17 years was only . Some locations in the

Sahara Desert The Sahara (, ) is a desert spanning across North Africa. With an area of , it is the largest hot desert in the world and the list of deserts by area, third-largest desert overall, smaller only than the deserts of Antarctica and the northern Ar ...

such as

Kufra Kufra () is a basinBertarelli (1929), p. 514. and oasis group in the Kufra District of southeastern Cyrenaica in Libya. At the end of the 19th century, Kufra became the centre and holy place of the Senussi order. It also played a minor role in ...

Libya Libya, officially the State of Libya, is a country in the Maghreb region of North Africa. It borders the Mediterranean Sea to the north, Egypt to Egypt–Libya border, the east, Sudan to Libya–Sudan border, the southeast, Chad to Chad–L ...

, record an even drier of rainfall annually. The official weather station in

Death Valley Death Valley is a desert valley in Eastern California, in the northern Mojave Desert, bordering the Great Basin Desert. It is thought to be the Highest temperature recorded on Earth, hottest place on Earth during summer. Death Valley's Badwat ...

, United States reports annually, but in 40 months between 1931 and 1934 a total of just of rainfall was measured. To determine whether a location has an arid climate, the precipitation threshold is determined. The precipitation threshold (in millimetres) involves first multiplying the average annual temperature in °C by 20, then adding 280 if 70% or more of the total precipitation is in the high-sun summer half of the year (April through September in the

Northern Hemisphere The Northern Hemisphere is the half of Earth that is north of the equator. For other planets in the Solar System, north is defined by humans as being in the same celestial sphere, celestial hemisphere relative to the invariable plane of the Solar ...

, or October through March in the Southern), or 140 if 30–70% of the total precipitation is received during the applicable period, or 0 if less than 30% of the total precipitation is so received there. If the area's annual precipitation is less than half the threshold (50%), it is classified as a ''BW'' (desert climate), while 50–100% of the threshold results in a

semi-arid A semi-arid climate, semi-desert climate, or steppe climate is a aridity, dry climate sub-type. It is located on regions that receive precipitation below Evapotranspiration#Potential evapotranspiration, potential evapotranspiration, but not as l ...

climate.

Hot desert climates

Hot desert climates (''BWh'') are typically found under the

subtropical ridge The horse latitudes are the latitudes about 30 degrees north and south of the Equator. They are characterized by sunny skies, calm winds, and very little precipitation. They are also known as subtropical ridges or highs. It is a high-pressur ...

in the lower middle latitudes or the

subtropics The subtropical zones or subtropics are geographical and climate zones immediately to the north and south of the tropics. Geographically part of the temperate zones of both hemispheres, they cover the middle latitudes from to approximately ...

, often between 20° and 33° north and south latitudes. In these locations, stable descending air and high pressure aloft clear clouds and create hot, arid conditions with intense sunshine. Hot desert climates are found across vast areas of

North Africa North Africa (sometimes Northern Africa) is a region encompassing the northern portion of the African continent. There is no singularly accepted scope for the region. However, it is sometimes defined as stretching from the Atlantic shores of t ...

West Asia West Asia (also called Western Asia or Southwest Asia) is the westernmost region of Asia. As defined by most academics, UN bodies and other institutions, the subregion consists of Anatolia, the Arabian Peninsula, Iran, Mesopotamia, the Armenian ...

, northwestern parts of the

Indian Subcontinent The Indian subcontinent is a physiographic region of Asia below the Himalayas which projects into the Indian Ocean between the Bay of Bengal to the east and the Arabian Sea to the west. It is now divided between Bangladesh, India, and Pakista ...

, southwestern Africa, interior Australia, the

Southwestern United States The Southwestern United States, also known as the American Southwest or simply the Southwest, is a geographic and cultural list of regions of the United States, region of the United States that includes Arizona and New Mexico, along with adjacen ...

, northern

Mexico Mexico, officially the United Mexican States, is a country in North America. It is the northernmost country in Latin America, and borders the United States to the north, and Guatemala and Belize to the southeast; while having maritime boundar ...

, sections of southeastern

Spain Spain, or the Kingdom of Spain, is a country in Southern Europe, Southern and Western Europe with territories in North Africa. Featuring the Punta de Tarifa, southernmost point of continental Europe, it is the largest country in Southern Eur ...

, the coast of

Peru Peru, officially the Republic of Peru, is a country in western South America. It is bordered in the north by Ecuador and Colombia, in the east by Brazil, in the southeast by Bolivia, in the south by Chile, and in the south and west by the Pac ...

and

Chile Chile, officially the Republic of Chile, is a country in western South America. It is the southernmost country in the world and the closest to Antarctica, stretching along a narrow strip of land between the Andes, Andes Mountains and the Paci ...

and parts of the Brazilian sertão. This makes hot deserts present in every continent except Antarctica. At the time of high sun (summer), scorching, desiccating heat prevails. Hot-month average temperatures are normally between , and midday readings of are common. The world's absolute heat records, over , are generally in the hot deserts, where the heat potential can be the highest on the planet. This includes the record of in

, which is currently considered the

highest temperature recorded on Earth The highest temperature recorded on Earth has been measured in three major ways: air, ground, and via satellite observation. Air measurements are used as the standard measurement due to persistent issues with unreliable ground and satellite rea ...

. Some deserts in the

tropics The tropics are the regions of Earth surrounding the equator, where the sun may shine directly overhead. This contrasts with the temperate or polar regions of Earth, where the Sun can never be directly overhead. This is because of Earth's ax ...

consistently experience very high temperatures all year long, even during wintertime. These locations feature some of the highest annual average temperatures recorded on Earth, exceeding , up to nearly in Dallol, Ethiopia. This last feature is seen in sections of Africa and

Arabia The Arabian Peninsula (, , or , , ) or Arabia, is a peninsula in West Asia, situated north-east of Africa on the Arabian plate. At , comparable in size to India, the Arabian Peninsula is the largest peninsula in the world. Geographically, the ...

. During colder periods of the year, night-time temperatures can drop to freezing or below due to the exceptional radiation loss under the clear skies. However, temperatures rarely drop far below freezing under the hot subtype. Hot desert climates can be found in the deserts of

such as the wide

, the

Libyan Desert The Libyan Desert (not to be confused with the Libyan Sahara) is a geographical region filling the northeastern Sahara Desert, from eastern Libya to the Western Desert (Egypt), Western Desert of Egypt and far northwestern Sudan. On medieval m ...

or the

Nubian Desert The Nubian Desert ( ) is in the eastern region of the Sahara, Sahara Desert, spanning approximately 400,000 km2 of northeastern Sudan and northern Eritrea, between the Nile and the Red Sea. The arid region is rugged and rocky and contains s ...

; deserts of the

Horn of Africa The Horn of Africa (HoA), also known as the Somali Peninsula, is a large peninsula and geopolitical region in East Africa.Robert Stock, ''Africa South of the Sahara, Second Edition: A Geographical Interpretation'', (The Guilford Press; 2004), ...

such as the

Danakil Desert The Danakil Desert (or Afar Desert) is a desert in northeast Ethiopia, southern Eritrea, and northwestern Djibouti. Situated in the Afar Triangle, it stretches across of Desert climate, arid terrain. It is inhabited by a few Afar people, Afar, w ...

or the Grand Bara Desert; deserts of

Southern Africa Southern Africa is the southernmost region of Africa. No definition is agreed upon, but some groupings include the United Nations geoscheme for Africa, United Nations geoscheme, the intergovernmental Southern African Development Community, and ...

such as the

Namib Desert The Namib ( ; ) is a coastal desert in Southern Africa. According to the broadest definition, the Namib stretches for more than along the Atlantic coasts of Angola, Namibia, and northwest South Africa, extending southward from the Carunjamba Ri ...

or the

Kalahari Desert The Kalahari Desert is a large semiarid climate, semiarid sandy savanna in Southern Africa covering including much of Botswana as well as parts of Namibia and South Africa. It is not to be confused with the Angolan, Namibian, and South African ...

; deserts of

such as the Arabian Desert, or the

Syrian Desert The Syrian Desert ( ''Bādiyat Ash-Shām''), also known as the North Arabian Desert, the Jordanian steppe, or the Badiya, is a region of desert, semi-desert, and steppe, covering about of West Asia, including parts of northern Saudi Arabia, ea ...

; deserts of

South Asia South Asia is the southern Subregion#Asia, subregion of Asia that is defined in both geographical and Ethnicity, ethnic-Culture, cultural terms. South Asia, with a population of 2.04 billion, contains a quarter (25%) of the world's populatio ...

such as Dasht-e Lut and

Dasht-e Kavir Dasht-e Kavir ( in classical Persian, from ''khwar'' (low), and ''dasht'' (plain, flatland)) or the Kavir Desert, also known as Kavir-e Namak or the Great Salt Desert, is a large desert lying in the middle of the Iranian Plateau. It is about ...

of Iran or the

Thar Desert The Thar Desert (), also known as the Great Indian Desert, is an arid region in the north-western part of the Indian subcontinent that covers an area of in India and Pakistan. It is the world's 18th-largest desert, and the world's 9th-large ...

of India and Pakistan; deserts of the United States and Mexico such as the

Mojave Desert The Mojave Desert (; ; ) is a desert in the rain shadow of the southern Sierra Nevada mountains and Transverse Ranges in the Southwestern United States. Named for the Indigenous peoples of the Americas, indigenous Mohave people, it is located pr ...

, the

Sonoran Desert The Sonoran Desert () is a hot desert and ecoregion in North America that covers the northwestern Mexican states of Sonora, Baja California, and Baja California Sur, as well as part of the Southwestern United States (in Arizona and California). It ...

or the Chihuahuan Desert; deserts of Australia such as the

Simpson Desert The Simpson Desert is a large area of dry, red sandy plain and dunes in the Northern Territory, South Australia and Queensland in central Australia. It is the fourth-largest Deserts of Australia, Australian desert, with an area of . The Wangka ...

or the

Great Victoria Desert The Great Victoria Desert is a sparsely populated desert ecoregion and Interim Biogeographic Regionalisation for Australia, interim Australian bioregion in Western Australia and South Australia. History In 1875, British-born Australian explore ...

and many other regions. In

Europe Europe is a continent located entirely in the Northern Hemisphere and mostly in the Eastern Hemisphere. It is bordered by the Arctic Ocean to the north, the Atlantic Ocean to the west, the Mediterranean Sea to the south, and Asia to the east ...

, the hot desert climate can only be found on southeastern coast of

as well as small inland parts of southeastern, especially parts of the

Tabernas Desert The Tabernas Desert () is a desert located within Spain's south-eastern province of Almería. It is in the interior, about north of the provincial capital Almería, in the Tabernas municipality in Andalusia. It is the only desert in Europe, ...

Hot deserts are lands of extremes: most of them are among the hottest, the driest, and the sunniest places on Earth because of nearly constant high pressure; the almost permanent removal of low-pressure systems, dynamic fronts, and atmospheric disturbances; sinking air motion; dry atmosphere near the surface and aloft; the exacerbated exposure to the sun where solar angles are always high makes this desert inhospitable to most species.

Cold desert climates

Cold desert climates (''BWk'') usually feature hot (or warm in a few instances), dry summers, though summers are not typically as hot as hot desert climates. Unlike hot desert climates, cold desert climates tend to feature cold, dry winters. Snow tends to be rare in regions with this climate. The

Gobi Desert The Gobi Desert (, , ; ) is a large, cold desert and grassland region in North China and southern Mongolia. It is the sixth-largest desert in the world. The name of the desert comes from the Mongolian word ''gobi'', used to refer to all of th ...

in northern China and Mongolia is one example of a cold desert. Though hot in the summer, it shares the freezing winters of the rest of Inner Asia. Summers in South America's

are mild, with only slight temperature variations between seasons. Cold desert climates are typically found at higher altitudes than hot desert climates and are usually drier than hot desert climates. Cold desert climates are typically located in temperate zones in the 30s and 40s latitudes, usually in the leeward

rain shadow A rain shadow is an area of significantly reduced rainfall behind a mountainous region, on the side facing away from prevailing winds, known as its leeward side. Evaporated moisture from body of water, bodies of water (such as oceans and larg ...

of high mountains, restricting precipitation from the westerly winds. An example of this is the

Patagonian Desert The Patagonian Desert, also known as the Patagonian Steppe, is the largest desert in Argentina and is the list of deserts by area, eighth-largest desert in the world by area, occupying approx. 673,000 square kilometres (260,000 mi2). It is l ...

in Argentina, bounded by the Andes ranges to its west. In the case of Central Asia, mountains restrict precipitation from the eastern monsoon. The Kyzyl Kum, Taklamakan and Katpana Desert deserts of

Central Asia Central Asia is a region of Asia consisting of Kazakhstan, Kyrgyzstan, Tajikistan, Turkmenistan, and Uzbekistan. The countries as a group are also colloquially referred to as the "-stans" as all have names ending with the Persian language, Pers ...

are other significant examples of ''BWk'' climates. The

Ladakh Ladakh () is a region administered by India as a union territory and constitutes an eastern portion of the larger Kashmir region that has been the subject of a Kashmir#Kashmir dispute, dispute between India and Pakistan since 1947 and India an ...

region and the city of

Leh Leh () is a city in Indian-administered Ladakh in the Kashmir#Kashmir_dispute, disputed Kashmir region. The application of the term "administered" to the various regions of Kashmir and a mention of the Kashmir dispute is supported by the WP:TE ...

in the Great Himalayas in India also have a cold desert climate. In North America, the cold desert climate occurs in the drier parts of the

Great Basin Desert The Great Basin Desert is part of the Great Basin between the Sierra Nevada and the Wasatch Range in the western United States. The desert is a geographical region that largely overlaps the Great Basin shrub steppe defined by the World Wildlife ...

and the

Bighorn Basin The Bighorn Basin is a plateau region and intermontane basin, approximately 100 miles (160 km) wide, in north-central Wyoming in the United States. It is bounded by the Absaroka Range on the west, the Pryor Mountains on the north, the Bigho ...

in Big Horn and Washakie County in

Wyoming Wyoming ( ) is a landlocked U.S. state, state in the Mountain states, Mountain West subregion of the Western United States, Western United States. It borders Montana to the north and northwest, South Dakota and Nebraska to the east, Idaho t ...

. The Hautes Plaines, located in the northeastern section of

Morocco Morocco, officially the Kingdom of Morocco, is a country in the Maghreb region of North Africa. It has coastlines on the Mediterranean Sea to the north and the Atlantic Ocean to the west, and has land borders with Algeria to Algeria–Morocc ...

and in

Algeria Algeria, officially the People's Democratic Republic of Algeria, is a country in the Maghreb region of North Africa. It is bordered to Algeria–Tunisia border, the northeast by Tunisia; to Algeria–Libya border, the east by Libya; to Alger ...

, is another prominent example of a cold desert climate. In

, this climate only occurs in some inland parts of southeastern Spain, such as in Lorca. Polar climate desert areas in the Arctic and Antarctic regions receive very little precipitation during the year owing to the cold, dry air freezing most precipitation. Polar desert climates have desert-like features that occur in cold desert climates, including intermittent streams, hypersaline lakes, and extremely barren terrain in unglaciated areas such as the

McMurdo Dry Valleys The McMurdo Dry Valleys are a row of largely Antarctic oasis, snow-free valleys in Antarctica, located within Victoria Land west of McMurdo Sound. The Dry Valleys experience extremely low humidity and surrounding mountains prevent the flow of ...

of Antarctica. These areas are generally classified as having

polar climate The polar climate regions are characterized by a lack of warm summers but with varying winters. Every month a polar climate has an average temperature of less than . Regions with a polar climate cover more than 20% of the Earth's area. Most of ...

s because they have average summer temperatures below even if they have some characteristics of extreme non-polar deserts.

Climate charts

Hot deserts

Cold deserts

References

External links

Desert climate summary

{{Authority control Climate of Africa Climate of Asia Climate of Australia Climate of North America Climate of South America

climate Climate is the long-term weather pattern in a region, typically averaged over 30 years. More rigorously, it is the mean and variability of meteorological variables over a time spanning from months to millions of years. Some of the meteoro ...

+Climate Köppen climate types

Precipitation

Hot desert climates

Cold desert climates

Climate charts

Hot deserts

Cold deserts

See also

References

External links