Antarctica holds the distinction of being the coldest, windiest, and driest continent on Earth, a landmass defined by its extremes. Determining how cold Antarctica gets at night is complex because the continent is vast, and temperatures vary dramatically by location and season. The most extreme cold occurs in the high-altitude interior, where long periods without sunlight allow temperatures to plummet far below what is experienced anywhere else on the planet.
Record Low Temperatures
The lowest air temperature ever directly measured on Earth was recorded at the Russian Vostok Station, deep in the interior of East Antarctica. On July 21, 1983, the air temperature registered \(-89.2^{\circ}\text{C}\) (\(-128.6^{\circ}\text{F}\)). This measurement was taken using a ground-based thermometer, which is the official standard for record air temperature. For comparison, average winter temperatures on the high central plateau often hover below \(-60^{\circ}\text{C}\) (\(-76^{\circ}\text{F}\)).
Even colder temperatures have been detected, though not by a traditional thermometer. Satellite observations identified areas on the East Antarctic Plateau where the surface snow temperature regularly drops to about \(-98^{\circ}\text{C}\) (\(-144^{\circ}\text{F}\)). This “skin temperature” implies an estimated air temperature just above the surface of roughly \(-94^{\circ}\text{C}\) (\(-137^{\circ}\text{F}\)). The combination of extreme cold and wind creates a lower “felt temperature” due to the wind chill effect. Wind chill measures the rate of heat loss from exposed skin, which can make a \(-40^{\circ}\text{C}\) day feel like \(-70^{\circ}\text{C}\) or colder when the wind picks up, rapidly increasing the risk of frostbite.
Geographic Differences in Cold
Temperatures across Antarctica are not uniform, varying greatly between the high inland plateau and the coast. The interior, such as the area around the South Pole and Vostok, features the most consistently low temperatures due to its high elevation and remoteness from the ocean. Here, winter monthly means routinely fall below \(-60^{\circ}\text{C}\). The high altitude and continental isolation allow for maximum radiative cooling, which drives these temperature extremes.
Conversely, the coastal regions experience a more moderate climate. Along the coast, winter monthly mean temperatures typically range from \(-10^{\circ}\text{C}\) to \(-30^{\circ}\text{C}\). The Antarctic Peninsula, which juts northward into the Southern Ocean, has the most moderate climate, with temperatures sometimes briefly rising toward freezing even in winter. The surrounding ocean acts as a heat sink, moderating the extreme cold, a factor absent in the high interior.
Why Antarctica is So Cold
Several physical factors combine to make Antarctica the coldest place on Earth. The primary factor is the continent’s high average elevation, which sits at approximately 2,500 meters (8,200 feet) above sea level. Air naturally cools as it rises, meaning the vast, high-altitude ice sheet starts colder than sea-level locations.
The massive ice sheet itself also contributes to the extreme cold through the albedo effect. Snow and ice are highly reflective, and the white surface reflects up to 85% of incoming solar radiation back into space. This reflection prevents the sun’s energy from being absorbed and converted into heat, limiting warming during the summer months.
The air over the continent is extremely dry, effectively classifying Antarctica as a polar desert. This lack of moisture means there is very little water vapor to trap heat, allowing warmth to quickly radiate away into the atmosphere. The cold, dense air that forms over the plateau often flows downhill toward the coast, creating powerful, localized katabatic winds. These winds exacerbate the cold near the coast and prevent warmer, maritime air from penetrating the interior.
The Concept of Antarctic Night
The term “night” in Antarctica must be understood in the context of the continent’s unique polar geography. For locations south of the Antarctic Circle, the winter season brings polar night, where the sun remains below the horizon for months at a time. In the deepest interior, such as at the South Pole, this means a period of continuous darkness lasting approximately six months.
The coldest temperatures are achieved during this prolonged sunless period, not a standard 24-hour night cycle. The continuous absence of solar heating allows the surface and the air above it to cool unchecked for an extended duration, leading to record lows. This extended period of darkness, combined with the other physical factors, is the reason Antarctica’s temperatures are so much more extreme than those in the Arctic.