Editing Polar climate (section)

{{Short description|Climate classification}}
[[File:Koppen-Geiger_Map_v2_E_1991–2020.svg|thumb|upright=1.8|Areas of polar climate according to  the [[Köppen climate classification]]:
{{legend|#E2E2E2|[[Tundra climate]] ''(ET)''}}
{{legend|#565656|[[Ice cap climate]] ''(EF)''}}]]
[[Image:Oblique rays 04 Pengo.svg|thumb|upright=1.25|Solar radiation has a lower intensity in polar regions because the angle at which it hits the earth is not as direct as at the equator. Another effect is that sunlight has to go through more atmosphere to reach the ground.<ref>{{cite web|url=http://www.hko.gov.hk/education/edu06nature/ele_srad_e.htm|title=Why is the equator very hot and the poles very cold?|last=Yung|first=Chung-hoi|publisher=Hong Kong Observatory|access-date=2010-12-02|archive-date=2018-06-14|archive-url=https://web.archive.org/web/20180614094310/http://www.hko.gov.hk/education/edu06nature/ele_srad_e.htm|url-status=dead}}</ref>]]

The '''polar climate''' regions are characterized by a lack of warm [[summer]]s but with varying [[winter]]s. Every month a polar climate has an average temperature of less than {{convert|10|C|F}}. Regions with a polar climate cover more than 20% of the Earth's area. Most of these regions are far from the [[equator]] and near the [[Polar regions of Earth|poles]], and in this case, winter days are extremely short and summer days are extremely long (they could last for the entirety of each season or longer). A polar climate consists of cool summers and very cold winters (or, in the case of ice cap climates, no real summer at all), which results in treeless [[tundra]]s, [[glacier]]s, or a permanent or semi-permanent layer of [[ice]]. It is identified with the letter '''E''' in the [[Köppen climate classification]].