The subtropics (sometimes also referred to as the warm temperate zone ) belong to the climatic zones of the earth . They lie in the geographical latitude between the tropics in the equatorial direction and the temperate zones in the direction of the poles , approximately between 25 and 40 degrees north or south latitude. These areas typically have tropical summers and non-tropical winters. They can be divided into dry, winter damp and always damp subtropics.
It is difficult to define the subtropics more precisely, as this zone is the most heterogeneous and fragmented of all climatic zones. Both moist laurel forest areas with mostly over 1,000 mm of annual precipitation and annual mean temperatures of 13 to 17 ° C (with many exceptions up or down to severe frost), winter-damp and summer-dry Mediterranean climates with 300 to 1,000 mm of precipitation (with many exceptions) and 12 to 18 ° C, as well as extremely dry hot deserts with almost 0 to 200 mm of precipitation and average temperatures of over 20 ° C with maxima of up to 50 ° C are counted among the subtropics. Folkwin Geiger mentions only two things in common:
- Clearly pronounced thermal seasons with an average annual amplitude between 5 and 22 degrees
- With winter monthly temperatures of up to +4 ° C, frosts can occur almost everywhere, but these usually only occur on cloud-free winter nights and do not fall below −6 ° C
The dry subtropics have a growing season of 5 to 6 (7) months. The biodiversity of the plants is relatively low. There is a desert and steppe vegetation. Thorn bush plants are often found.
In some publications, only the Mediterranean climate is referred to as a warm temperate climate and assigned to the middle latitudes .
There is a 6 to 10 (11) month growing season. A specific type of formation dominates, the hard-leaf vegetation , which is characterized for the Mediterranean areas of the Mediterranean Sea and California by evergreen oak species such as holm oak , cork oak and Kermes oak as well as the semi- evergreen Macedonian oak . In Australia, two types of eucalyptus, Jarrah ( Eucalyptus marginata ) and Marri ( Eucalyptus calophylla ), are widespread in Mediterranean regions. In California there are many softwoods, among which the sequoia tree is of particular interest. In many areas the landscape is completely forestless due to early overexploitation . The forests of southwest Australia, the Cape region of South Africa, California and the Mediterranean are among the 25 most species-rich on earth due to their high endemic abundance .
East side climate
The maximum precipitation is in the summer half of the year.
There is a year-round vegetation period and a species-rich laurel forest with numerous lianas , but fewer epiphytes than in tropical forests. In Australia, typically eucalyptus forests. In the Caucasus , Afghanistan , northern Iran and eastern US species-rich deciduous forests with a high proportion of tertiary species. In south-east China, a global center of biodiversity, many original genera that otherwise became extinct have been preserved.
When considering mountain levels , the lowest level ( collin-planar level ) of subtropical mountains is sometimes called the subtropical level. In addition, it happens especially with botanists that the second ( montane level ) tropical mountains are also called subtropical . This can lead to confusion. Correctly, this altitude level of the tropics should be called supratropic .
- TU Berlin, Institute for Ecology, LV Kehl - Flora and vegetation of the (winter-humid) subtropics
- Comparison of the winter rainy climate on the west side and the subtropical east side climate ( Memento from May 2, 2015 in the Internet Archive )
- This designation is misleading: Some authors only use it for the Mediterranean climate, some for the cool-temperate climate and also the warm-temperate rainy climates according to Köppen / Geiger are in the cool-temperate zone.
- Heinz Nolzen (Ed.): Handbook of Geography Lessons. Vol. 12/2, Geozonen, Aulis Verlag Deubner & Co. KG, Cologne 1995, ISBN 978-3-7614-1619-8 , pp. 27, 115-116.
- Georg Grabherr: Color Atlas of Ecosystems of the Earth . Ulmer, Stuttgart 1997. ISBN 3-8001-3489-6 , pp. 140, 179, 222.
- Burkhard Hofmeister: The moderate latitudes: especially the cool temperate woodlands. Westermann, Braunschweig 1985, ISBN 978-3-89057-313-7 , p. 14.
- Identifiers of the most important climatic zones in Europe , zum.de, educational media on the Internet, accessed on October 26, 2015.
- Michael Richter (author), Wolf Dieter Blümel et al. (Ed.): Vegetation zones of the earth. 1st edition, Klett-Perthes, Gotha and Stuttgart 2001, ISBN 3-623-00859-1 . P. 300.