Polar climates, found near the Earth's North and South Poles, are characterized by consistently cold temperatures and the absence of warm summers. Covering over 20% of Earth's surface, these regions have average monthly temperatures below 10°C (50°F) year-round. In polar climates, summer temperatures are cool, and winters are extremely cold. Some areas, such as those with ice cap climates, experience no true summer at all. This leads to landscapes dominated by treeless tundra, glaciers, or permanent ice layers. The polar regions are distinct: the Arctic surrounds the North Pole, while Antarctica encompasses the South Pole. These areas receive less direct sunlight than other parts of the world, due to the shallow angle at which sunlight strikes. As a result, the energy is spread over a larger surface area, leading to lower temperatures. In the Arctic, summer temperatures average around 0°C (32°F), while winter temperatures can plunge to approximately −40°C (−40°F). Antarctica is even colder, with summer temperatures averaging −28.2°C (−18.8°F) and winter temperatures dropping to around −60°C (−76°F).
Polar climate subtypes and weather patterns
Polar climates are categorized into two main types: tundra (ET) and ice cap (EF) climates. Tundra climates experience at least one month with an average temperature above freezing (0°C or 32°F), which allows specialized plants to grow, although coniferous trees cannot thrive there. Conversely, ice cap climates maintain temperatures below freezing throughout the year, resulting in no plant life and continuous ice accumulation. Alpine climates, found at high altitudes, share similarities with tundra or ice cap climates but are distinguished primarily by elevation rather than latitude. Besides their cold temperatures, polar regions are also classified as deserts due to their extremely low humidity. The dry air limits cloud formation and precipitation, with some areas receiving less than 25 cm (10 inches) of moisture annually. Snowfall often does not melt due to persistently low temperatures, leading to the gradual accumulation of ice over millennia. This accumulated ice can form glaciers, which flow very slowly due to their massive size. Ice sheets, large glaciers exceeding 50,000 square kilometers (19,300 square miles), are found in Antarctica and Greenland. Historically, much of the Earth was covered by such ice sheets; today, Antarctica hosts the largest ice sheet, spanning over 14 million square kilometers (5.4 million square miles), while Greenland’s ice sheet is smaller. Ice caps, which cover areas less than 50,000 square kilometers (19,300 square miles) and typically have a dome shape, are smaller than ice sheets. Both ice sheets and ice caps consist of freshwater that has compacted over time. Sea ice, formed from the freezing of ocean water, is a thin layer that can reach up to 30 meters (98 feet) thick in some polar regions. This ice can persist year-round, covering about 15% of the world's oceans during certain periods.
Ice cap climate
An ice cap climate, classified under the Köppen climate system as EF, is characterized by consistently frigid conditions where no monthly average temperature rises above 0°C (32°F). This climate is predominantly found in high-altitude regions and polar zones, including Antarctica, Greenland, and some of the northernmost islands in Canada, Russia, and Norway's Svalbard Archipelago. In regions with an ice cap climate, the temperature remains too cold for ice or snow to melt, leading to the formation of permanent ice sheets. These ice sheets are immense, often miles thick, and slowly flow into surrounding waters. Continuous freezing temperatures result in minimal precipitation—primarily snow—making the surface largely devoid of vegetation. In contrast to tundra climates, which have a brief summer thaw and some plant life, ice caps remain perpetually icy with no vegetation. Antarctica and Greenland are the primary locations for ice cap climates. In the Arctic, Greenland is the only large landmass with an ice cap climate, although smaller islands near the Arctic Ocean also feature permanent ice caps. The Arctic Ocean’s influence moderates temperatures, preventing the extreme cold seen in Antarctica, where high-speed winds isolate the continent from warmer air masses. Ice cap climates also occur on high mountains around the world, including the Andes, Himalayas, Rockies, Caucasus, and Alps. Surface life in ice cap climates is sparse due to the harsh conditions. Vegetation is nearly nonexistent, though some mosses and lichens may appear in slightly warmer fringes. Animal life is limited but notable; for instance, polar bears are found in the Arctic, while Antarctica is home to penguins. Subglacial lakes, such as Lake Vostok in Antarctica, lie beneath the ice sheets, and while their ecosystems remain largely unexplored, scientists are keenly interested in potential microbial life.
Tundra climate
The tundra climate is a type of polar climate found in high latitudes and elevated mountain regions. According to the Köppen climate classification, it is labeled as ET. This climate type features at least one month where temperatures rise enough to melt snow (0°C or 32°F), but no month with an average temperature above 10°C (50°F). When this climate occurs at high elevations, it is referred to as an alpine climate. The ET category includes a range of precipitation patterns, but tundra climates are typically characterized by low rainfall and snowfall due to the chilly atmosphere's limited water vapor. Despite this, tundra areas often have soggy terrain, like swamps and bogs, due to minimal evaporation. Tundra vegetation is more influenced by local temperatures than by precipitation levels. As the third coldest climate type according to the Köppen system, tundra climates are generally colder than temperate climates but not as extreme as some subarctic climates. There is also a variant with milder winters found in places such as Iceland, the Aleutian Islands, and subantarctic islands.
Concerns
Global warming is having a particularly intense impact on the polar regions. Over the past three decades, Arctic temperatures have increased at roughly double the global average rate. This rapid warming could lead to the complete loss of summer sea ice in the Arctic by 2035. Similarly, Antarctica is experiencing significant ice sheet melting, even in its coldest areas. Ice and snow reflect sunlight, helping to cool the planet. As they melt, less heat is reflected, contributing to global temperature rises. Additionally, melting ice leads to rising sea levels and the release of methane from thawing permafrost. Methane is a potent greenhouse gas that exacerbates global warming. Thus, although the polar regions may seem distant, their changes have profound global implications, influencing climate patterns and conditions worldwide.
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Which feature is commonly associated with polar climates?
