Climate in Antarctica
The current climate in Antarctica and the Southern Ocean results from links and interactions between the inland ice sheet, the sea, sea ice, and the atmosphere, and their responses to climate drivers, past and present.
The climate in Antarctica is colder than in any other place on earth. The lowest temperature ever measured on earth, ‑89.2°C, was registered at Vostok in the interior of the Antarctic continent. Temperatures in inland Antarctica rarely rise to 0°C even in summer. Winter temperatures vary, but rarely exceed ‑30°C and sometimes drop to a frigid ‑70°C. The Antarctic Peninsula – what might be called the “tropical” part of Antarctica – has a relatively warm, maritime climate and along its coasts, the temperature stays just under 0°C for most of the year. The continent itself can be considered a desert; up on the Antarctic Plateau annual precipitation is just 25 to 50 mm. Very dry indeed.
The rotating air masses high above Antarctica entrain low pressure zones that circulate at the boundary between ocean and ice. Cold air sweeps down from the central plateau toward the ocean, particularly in spring and autumn. The wind can easily reach gale force speed, and in places where the wind flows through narrow valleys, it can attain a speed of 90 m/s (325 km/h).
Studies of the climatic history of Antarctica lay the foundation for understanding today’s climate and climate change. They enable us to understand the processes that led to our current interglacial period, and to define the magnitude of natural climatic variability on a geological time-scale. This allows us to judge when the climate change we currently see exceeds the natural variability. Studies of ancient climate also tell us that climate change is normal, and that changes can be surprising. At the same time, the research reveals that conditions created by humans in all likelihood cause changes in addition to the natural ones.