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Polar ecology is the relationship between plants and animals in a polar environment. Polar environments are in the Arctic and Antarctic regions. Arctic regions are in the Northern Hemisphere , and it contains land and the islands that surrounds it.
Arctic vegetation is largely controlled by the mean temperature in July, the warmest month. Arctic vegetation occurs in the tundra climate, where trees cannot grow.Tundra climate has two boundaries: the snow line, where permanent year-round snow and ice are on the ground, and the tree line, where the climate becomes warm enough for trees to grow. [7]
Nothofagus fusca, New Zealand. Antarctic flora are a distinct community of vascular plants which evolved millions of years ago on the supercontinent of Gondwana.Presently, species of Antarctica flora reside on several now separated areas of the Southern Hemisphere, including southern South America, southernmost Africa, New Zealand, Australia, and New Caledonia.
Visualization of the ice and snow covering Earth's northern and southern polar regions Northern Hemisphere permafrost (permanently frozen ground) in purple. The polar regions, also called the frigid zones or polar zones, of Earth are Earth's polar ice caps, the regions of the planet that surround its geographical poles (the North and South Poles), lying within the polar circles.
By contrast, salt-water frost flowers are more common -- especially in cold, polar regions. [3] [5] Sea ice is often broken apart by winds, tides and currents, leading to open water ‘leads’ that are exposed to extremely cold air temperatures. When these leads freeze over, forming thin ice, frost flowers often form in dense concentrations.
However, ocean currents also flow thousands of meters below the surface. These deep-ocean currents are driven by differences in the water's density, which is controlled by temperature (thermo) and salinity (haline). This process is known as thermohaline circulation. In the Earth's polar regions ocean water gets very cold, forming sea ice.
The Arctic region is a unique area among Earth's ecosystems. The cultures in the region and the Arctic indigenous peoples have adapted to its cold and extreme conditions. Life in the Arctic includes zooplankton and phytoplankton, fish and marine mammals, birds, land animals, plants, and human societies. [3] Arctic land is bordered by the subarctic.
Polar bear in Manitoba, Canada. November 2004. Polar seas is a collective term for the Arctic Ocean (about 4-5 percent of Earth's oceans) and the southern part of the Southern Ocean (south of Antarctic Convergence, about 10 percent of Earth's oceans). In the coldest years, sea ice can cover around 13 percent of the Earth's total surface at its ...