Subtropics

The subtropics are the geographical and climatical zone of the Earth immediately north and south of the tropical zone, which is bounded by the Tropic of Cancer and the Tropic of Capricorn, at latitudes 23.5°N and 23.5°S. The term "subtropical" describes the climatic region found adjacent to the tropics, usually between 23.5 and 40 degrees of latitude in both hemispheres.

Contents 1 Definition 2 Characteristics 3 Varieties by Köppen climate classification 3.1 Subtropical highland variety (Cwb) 3.2 Mediterranean climate 3.3 Humid subtropical climate 3.4 Subtropical semi-desert/desert climate[7] 4 Subtropical areas 5 Subtropical flora and landscapes 6 Charts of selected cities with varieties of the subtropical climates 6.1 Subtropical highland variety 6.2 Mediterranean climate 6.3 Humid subtropical climate 6.4 Subtropical semi-desert/desert climate 7 See also 8 References 9 External links

Definition

According to climatologist Glenn G. Trewartha, a subtropical region should have at least eight months with a mean temperature of 10 °C (50.0 °F) or above. His revision of the Köppen climate classification assigns to such areas the letter C, while others zones encompassed in the original Köppen group C class would be considered part of group.

American climatologist John F. Griffiths in his book Applied climatology described the subtropical zone as having a coldest month of between 6 °C (42.8 °F) and 18 °C (64.4 °F) and assigning to this group the letter B, while the original B group of Köppen taxonomy would be spread over the various temperature-based groups.

German climatologists Carl Troll and Karlheinz Paffen defined warmgemäßigte Zonen ("Warm temperate zones") plain and hilly lands having an average temperature of the coldest month between 2 °C (35.6 °F) and 13 °C (55.4 °F) in Northern Hemisphere and between 6 °C (42.8 °F) and 13 °C (55.4 °F) in Southern Hemisphere, excluding oceanic and continental climates. According to Troll-Paffen climate classification, generally exist one a large subtropical zone^[1] named Warmgemäßigt-subtropisches Zonenklima (en: warm-temperate subtropical zone) divided into seven smaller areas.^[2]

According to E. Neef climate classification subtropical zone divided into two parts: Winterregenklima der Westseiten (en: Rainy winters of the west sides) and Subtropisches Ostseitenklima (en: Eastern subtropical climate).^[3]

According to Wilhelm Lauer & Peter Frankenberg climate classification subtropical zone divided into three parts: hoch-continental (high-continental), kontinental (continental) and maritim (maritime).^[4]

According to Siegmund/Frankenberg climate classification, subtropical is one of six climate zones in the world.^[5]

Characteristics

In subtropical climates the winters are relatively warm-mild, but not as hot as the summer season. These climates rarely—if ever—see frost or snow and plants such as palm, citrus and many broadleaf evergreens flourish, in contrast to the hardier deciduous and coniferous trees which dominate midlatitude climates. As one moves toward the tropical side the slight winter cool season disappears altogether, while at the poleward threshold of the subtropics the winters become much cooler.

Rainfall patterns vary widely throughout the subtropics including hot deserts, savannas, monsoon forests, humid forests and the warmer parts of the Mediterranean climate zone. Subtropical regions include most of California and southern Europe (Mediterranean or dry-summer subtropical climate), the low deserts of the Southwest USA (hot arid type), the Gulf Coast and most of Florida (humid subtropical climate), northern India (monsoon), southeast China (humid), the middle part of South America (varied), much of Australia (varied) and coastal South Africa.

Varieties by Köppen climate classification

Subtropical highland variety (Cwb)

The Subtropical Highland variety (Köppen climate classification: Cwb) of the oceanic climate exists in elevated portions of the world that are either within the tropics or subtropics, though it is typically found in mountainous locations in some tropical countries. Despite the latitude, due to the higher altitudes of these regions, it tends to share characteristics with oceanic climates, though it also tends to experience noticeably drier weather during the "low-sun" season.

In locations outside the tropics, other than the drying trend in the winter, Subtropical Highland climates tend to be essentially identical to an oceanic climate, complete with mild summers, noticeably cooler winters and in some instances, some snowfall. In the tropics, a Subtropical Highland climate tends to feature spring-like weather year-round. Temperatures here remain relatively constant throughout the year and snowfall is seldom seen. Areas with this climate feature monthly averages below 22 °C (72 °F) but above −3 °C (27 °F) (or 0 °C (32 °F) using American standards). At least one month's average temperature is below 18 °C (64 °F). Without the elevation, many of these regions would likely feature either tropical or humid subtropical climates. These regions usually carry a Cwb or Cfb designation. .

This type of climate exists in parts of east, south and south-eastern Africa, some mountainous areas across southern Europe, sections of mountainous Latin America, some mountainous areas across Southeast Asia, higher elevations of the southern Appalachians, and parts of the Himalayas. It also occurs in a few areas of Australia, although average high temperatures during summers there tend to be higher and the climate drier than is typical of Subtropical Highland Climates, with maximums sometimes exceeding 40 °C (104 °F).^[6]

Mediterranean climate

The Mediterranean climate (Köppen climate classification: Csa) is a particular variety of the subtropical climate found around the Mediterranean Sea, the largest area where this climate type is found, but it also prevails in much of California, in parts of Western and South Australia, in southwestern South Africa, in isolated regions of Central Asia, and in parts of central Chile.

The climate is characterized by warm to hot, dry summers and mild to cool, wet winters. Mediterranean climate zones are associated with the five large subtropical high pressure cells of the oceans, the Azores High, South Atlantic High, North Pacific High, South Pacific High, and the Indian Ocean High which cause the dry summers.

Humid subtropical climate

The humid subtropical climate is a subtropical climate type characterized by hot, humid summers and warm to cool winters. The average annual precipitation may either be evenly distributed throughout the year (Köppen climate classification: Cfa) or marked by a dry season or drying trend during winter (Köppen climate classification: Cwa).

Humid subtropical climates lie on the southeast side of all continents, generally between latitudes 25° and 40° north and south. However, in Europe, it extends above latitude 45° N, covering regions such as the Po Valley of Italy, which includes Venice, the Toulouse region of France, and along the Black Sea coast. In East Asia, the influence of the Siberian anticyclone depresses winter temperatures, pushing the southern boundary of this regime to around China's Hainan Island, at latitude 20° N.

In subtropical climates the winters are relatively warm-mild, but not hot as the summer season. These climates rarely—if ever—see frost or snow. As one moves toward the tropical side the slight winter cool season disappears altogether, while at the poleward threshold of the subtropics the winters become much cooler.

Subtropical semi-desert/desert climate^[7]

Subtropical areas

Examples of subtropical cities and areas around the world include (see map above for more details):

In Africa

• North Africa: Algiers, Algeria; Alexandria, Egypt; Casablanca, Morocco; Tripoli, Libya; Tunis, Tunisia;
• Southern Africa: Cape Town, Durban and East London; Maseru, Lesotho and Natal, South Africa.
• The part of Atlantic Ocean, areas on the islands of Europe around the coast of Africa: Las Palmas, Spain; Funchal, Portugal.

In the Americas

• United States: Atlanta, Georgia; Austin, Texas;Brownsville, Texas; Birmingham, Alabama; Charleston, South Carolina, Charlotte, North Carolina; Columbia, South Carolina; Dallas, Texas; Houston, Texas; Jacksonville, Florida; Las Vegas, Nevada; Los Angeles, California; Little Rock, Arkansas; Memphis, Tennessee; Nashville, Tennessee;St. George, Utah; New Orleans, Louisiana; Norfolk, Virginia; Phoenix, Arizona; Raleigh, North Carolina; Richmond, Virginia; Sacramento, California; San Antonio, Texas; San Diego, California; San Jose, California; San Francisco Bay Area; Savannah, Georgia; Tampa, Florida; Tucson, Arizona; with Washington, D.C., Charleston, West Virginia, Philadelphia, Pennsylvania, Cincinnati, Ohio, New York City, and Cape Cod, Massachusetts barely making qualifications on the northern extent.

• Mexico: Monterrey, Hermosillo, Cd. Juárez, Tijuana, Mexicali.
• Brazil: São Paulo, Santa Catarina, Rio Grande do Sul, Paraná, Mato Grosso do Sul.
• South America: Buenos Aires, Argentina; Montevideo, Uruguay; Santiago, Chile; Valparaíso, Chile; Lima, Perú; and Asunción, Paraguay.

In Eurasia

• Azerbaijan: Baku
• Mainland China: Nanjing, Shanghai, Hangzhou, Hefei, Nanchang, Fuzhou, Xiamen, Shenzhen, Guangzhou, Nanning, Changsha, Wuhan, Chongqing, Chengdu ^[8]
• Hong Kong
• Macau
• Taiwan: Taipei; Kaohsiung (borders on a true tropical climate)
• Japan: Shikoku, Kyūshū, Okinawa, Honshū
• European Union: Inland areas around the Mediterranean including a major part of the Iberian Peninsula, Apennine Peninsula and Balkan Peninsula. Major metropolises (urban area above 1 million people): Madrid; Barcelona; Milan; Athens; Lisbon; Rome; Naples; Porto; Marseilles; Turin; Valencia; Nice. Other places: Malta and Gibraltar.
• Georgia: Batumi, Sukhumi.
• India: Amritsar, and New Delhi.
• Pakistan: Islamabad, Peshawar, Muzaffarabad, Quetta, Mardan
• Russia: Sochi, Tuapse, Gelendzhik.
• Philippines: Baguio, Batanes.
• Turkey: Adana, Antalya, İzmir, Mersin.
• Middle East: Coastal Iran, Persian Gulf; Baghdad, Iraq; Israel; Northern Saudi Arabia; Beirut, Lebanon and Latakia, Syria.
• Ukraine: Yalta, Sevastopol, Simferopol barely making qualifications on the northern extent.
• Vietnam: Hanoi, Hai Phong, Da Lat.

In Oceania

• Australia: New South Wales (though not most of the Tablelands and Highland regions), parts of Queensland, Western Australia, South Australia, and Victoria.
• New Zealand: The northern part of North Island, restricted to the Northland Region.

Subtropical flora and landscapes

Charts of selected cities with varieties of the subtropical climates

Subtropical highland variety

Mexico City
Climate chart (explanation)
J F M A M J J A S O N D     11   21 6     4.3   23 7     10   26 9     26   27 11     56   27 12     135   25 12     175   23 12     169   23 12     145   22 12     67   22 10     12   22 8     6   21 7 Average max. and min. temperatures in °C Precipitation totals in mm Source: WMO
Imperial conversion J F M A M J J A S O N D     0.4   70 42     0.2   73 45     0.4   78 49     1   80 51     2.2   80 53     5.3   76 54     6.9   73 53     6.7   74 53     5.7   72 53     2.6   72 50     0.5   71 46     0.2   69 44 Average max. and min. temperatures in °F Precipitation totals in inches

Bogotá
Climate chart (explanation)
J F M A M J J A S O N D     33   20 9     43   20 10     66   20 10     111   19 10     94   19 10     57   18 10     41   18 10     49   18 10     73   19 10     115   19 10     88   19 10     54   19 10 Average max. and min. temperatures in °C Precipitation totals in mm Source: HKO
Imperial conversion J F M A M J J A S O N D     1.3   67 49     1.7   67 50     2.6   67 50     4.4   67 50     3.7   66 50     2.2   65 50     1.6   65 50     1.9   65 50     2.9   66 50     4.5   66 50     3.5   66 50     2.1   67 50 Average max. and min. temperatures in °F Precipitation totals in inches

Antananarivo
Climate chart (explanation)
J F M A M J J A S O N D     270   28 17     257   26 17     183   25 16     51   25 15     20   23 13     7.2   21 11     11   20 10     15   21 10     9.5   23 11     67   25 13     171   26 15     304   26 16 Average max. and min. temperatures in °C Precipitation totals in mm Source: WMO
Imperial conversion J F M A M J J A S O N D     11   82 62     10   79 62     7.2   78 61     2   77 59     0.8   73 55     0.3   70 51     0.4   68 51     0.6   69 51     0.4   73 52     2.6   77 56     6.7   79 59     12   78 61 Average max. and min. temperatures in °F Precipitation totals in inches

Mediterranean climate

Barcelona
Climate chart (explanation)
J F M A M J J A S O N D     41   14 5     29   15 5     42   16 7     49   18 9     59   21 12     42   24 16     20   28 19     61   28 19     85   26 17     91   22 13     58   17 8     51   15 6 Average max. and min. temperatures in °C Precipitation totals in mm Source: WMO[9]
Imperial conversion J F M A M J J A S O N D     1.6   56 40     1.1   58 42     1.7   61 44     1.9   64 47     2.3   69 54     1.7   76 60     0.8   82 65     2.4   82 67     3.3   78 62     3.6   71 55     2.3   63 47     2   58 42 Average max. and min. temperatures in °F Precipitation totals in inches

Los Angeles
Climate chart (explanation)
J F M A M J J A S O N D     85   20 9     94   21 10     80   21 11     21   23 12     7.9   24 14     1.5   26 16     0.3   29 18     3.3   29 19     8.1   29 18     9.4   26 16     27   23 11     49   20 9 Average max. and min. temperatures in °C Precipitation totals in mm Source: NOAA
Imperial conversion J F M A M J J A S O N D     3.3   68 49     3.7   70 50     3.1   70 52     0.8   73 54     0.3   74 58     0.1   80 61     0   84 65     0.1   85 66     0.3   83 65     0.4   79 60     1.1   73 53     1.9   69 48 Average max. and min. temperatures in °F Precipitation totals in inches

Cape Town
Climate chart (explanation)
J F M A M J J A S O N D     15   26 16     17   27 16     20   25 14     41   23 12     69   20 9     93   18 8     82   18 7     77   18 8     40   19 9     30   21 11     14   24 13     17   25 15 Average max. and min. temperatures in °C Precipitation totals in mm Source: HKO
Imperial conversion J F M A M J J A S O N D     0.6   79 60     0.7   80 60     0.8   78 58     1.6   73 53     2.7   69 49     3.7   65 46     3.2   64 45     3   64 46     1.6   67 48     1.2   70 51     0.6   74 56     0.7   77 59 Average max. and min. temperatures in °F Precipitation totals in inches

Humid subtropical climate

Hong Kong
Climate chart (explanation)
J F M A M J J A S O N D     25   19 14     52   19 14     71   22 17     189   25 21     330   28 24     388   30 26     374   31 27     445   31 26     288   30 26     152   28 23     35   24 19     35   20 16 Average max. and min. temperatures in °C Precipitation totals in mm Source: HKO
Imperial conversion J F M A M J J A S O N D     1   65 57     2   65 58     2.8   71 62     7.4   77 69     13   83 75     15   87 79     15   88 80     18   88 80     11   86 78     6   82 74     1.4   75 67     1.4   69 60 Average max. and min. temperatures in °F Precipitation totals in inches

São Paulo
Climate chart (explanation)
J F M A M J J A S O N D     239   27 19     217   28 19     160   27 18     76   25 16     74   23 14     56   22 12     44   22 12     39   23 13     81   24 14     124   25 15     146   26 17     201   26 18 Average max. and min. temperatures in °C Precipitation totals in mm Source: HKO
Imperial conversion J F M A M J J A S O N D     9.4   81 66     8.5   82 66     6.3   81 65     3   77 61     2.9   73 57     2.2   71 54     1.7   71 53     1.5   74 55     3.2   75 57     4.9   77 60     5.7   79 62     7.9   79 64 Average max. and min. temperatures in °F Precipitation totals in inches

Brisbane
Climate chart (explanation)
J F M A M J J A S O N D     114   30 21     130   30 21     94   29 20     60   27 17     64   24 14     56   22 12     22   22 10     42   23 11     33   26 14     84   27 16     111   28 19     158   29 20 Average max. and min. temperatures in °C Precipitation totals in mm Source: BoM
Imperial conversion J F M A M J J A S O N D     4.5   87 71     5.1   86 71     3.7   84 68     2.4   81 63     2.5   76 56     2.2   72 53     0.9   71 50     1.6   74 51     1.3   78 57     3.3   80 61     4.4   82 65     6.2   85 69 Average max. and min. temperatures in °F Precipitation totals in inches

Subtropical semi-desert/desert climate

Zaragoza
Climate chart (explanation)
J F M A M J J A S O N D     22   10 2     20   13 4     20   17 5     35   19 7     44   23 11     31   28 15     18   32 18     17   31 18     27   27 15     30   21 10     30   14 6     23   11 4 Average max. and min. temperatures in °C Precipitation totals in mm Source: Agencia Estatal de Meteorología
Imperial conversion J F M A M J J A S O N D     0.9   51 36     0.8   56 38     0.8   62 41     1.4   66 45     1.7   74 52     1.2   82 59     0.7   89 64     0.7   88 64     1.1   80 58     1.2   69 51     1.2   58 42     0.9   51 38 Average max. and min. temperatures in °F Precipitation totals in inches

Cairo
Climate chart (explanation)
J F M A M J J A S O N D     5   19 9     3.8   20 10     3.8   24 12     1.1   28 15     0.5   32 18     0.1   34 20     0   35 22     0   34 22     0   33 21     0.7   29 17     3.8   25 14     5.9   20 10 Average max. and min. temperatures in °C Precipitation totals in mm Source: WMO
Imperial conversion J F M A M J J A S O N D     0.2   66 48     0.1   69 49     0.1   74 53     0   83 58     0   90 64     0   93 68     0   94 72     0   94 72     0   91 69     0   85 63     0.1   77 57     0.2   69 51 Average max. and min. temperatures in °F Precipitation totals in inches

Lima
Climate chart (explanation)
J F M A M J J A S O N D     0.9   26 19     0.3   27 19     4.9   26 19     0   24 18     0.1   22 16     0.3   20 15     0.3   19 15     0.3   18 15     5.4   19 15     0.2   20 15     0   22 16     0.3   24 18 Average max. and min. temperatures in °C Precipitation totals in mm Source: WMO
Imperial conversion J F M A M J J A S O N D     0   78 66     0   80 67     0.2   79 67     0   76 64     0   71 61     0   67 60     0   66 59     0   65 58     0.2   66 58     0   68 59     0   71 62     0   75 64 Average max. and min. temperatures in °F Precipitation totals in inches

See also

• Humid subtropical climate
• Mediterranean climate
• Mediterranean forests, woodlands, and scrub
• Geographical zone

References

External links

• Study Shows Ocean “Deserts” are Expanding from NOAA, March 5, 2008
• Expanding tropics 'a threat to millions' from The Independent, 3 December 2007