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In physical geography, tundra (/ ˈ t ʌ n d r ə, ˈ t ʊ n-/) is a type of biome where tree growth is hindered by frigid temperatures and short growing seasons. There are three regions and associated types of tundra: Arctic , [ 2 ] Alpine , [ 2 ] and Antarctic .
Nearly all of Antarctica is covered by a sheet of ice that is, on average, at least 1,500 m (5,000 ft) thick. Antarctica contains 90% of the world's ice and more than 70% of its fresh water. If all the land-ice covering Antarctica were to melt—around 30 × 10 ^ 6 km 3 (7.2 × 10 ^ 6 cu mi) of ice—the seas would rise by over 60 m (200 ft). [22]
East Antarctica is colder than its western counterpart because of its higher elevation. Weather fronts rarely penetrate far into the continent, leaving the centre cold and dry, with moderate wind speeds. Heavy snowfalls are common on the coastal portion of Antarctica, where snowfalls of up to 1.22 m (48 in) in 48 hours have been recorded.
The climate generally covers areas at high altitudes and polar regions (60–90° north and south latitude), such as Antarctica and some of the northernmost islands of Canada and Russia. Most of Greenland is under the influence of an ice cap climate, although the coasts are prone to more influence from the sea, providing more tundra climates.
A tundra climate is characterized by having at least one month whose average temperature is above 0 °C (32 °F), while an ice cap climate has no months averaging above 0 °C (32 °F). [2] In a tundra climate, even coniferous trees cannot grow, but other specialized plants such as the arctic poppy can grow. In an ice cap climate, no plants can ...
Most of the interior of Antarctica is polar desert, despite the thick ice cover. Conversely, the McMurdo Dry Valleys of Antarctica , although they have had no ice for thousands of years due to katabatic wind but contain ephemeral streams and hypersaline lakes characteristic of extreme non-polar deserts, are not necessarily polar desert.
With detailed weather station and satellite data dating back only about 40 years, scientists wondered whether these events meant Antarctica had reached a tipping point, or a point of accelerated ...
Antarctica may have up to 17,000 species; [106] while 90% of the ocean around Antarctica is deeper than 1,000 m (3,281 ft), only 30% of the benthic-sample locations were taken at that depth. [107] On the Antarctic continental shelves , bethnic-zone biomass may increase due to oceanic warming, which is likely to be of most benefit to seaweed .