Antarctica is the highest, driest, coldest and windiest continent on earth. The lowest temperature yet recorded by ground measurements for the Antarctic Region, and for the whole world, was -89.2°C at Vostok station on 21 July 1983. But how warm does it get? That was the question posed last year to the World Meteorological Organization (WMO), the United Nations funded body that oversees meteorology and weather observations worldwide. A New Zealand scientist was part of an international group of experts who have identified the highest temperatures ever recorded in Antarctica.

Sunshine over the Antarctic Peninsula, which is one of the fastest warming regions on Earth. But how warm exactly does it get? (Photo: Katja Riedel)
Sunshine over the Antarctic Peninsula, which is one of the fastest warming regions on Earth. But how warm exactly does it get? (Photo: Katja Riedel)

Professor James Renwick from Victoria’s School of Geography, Environment and Earth Sciences is part of a World Meteorological Organisation Commission for Climatology (CCl) expert committee, which monitors weather and climate extremes around the globe. This committee announced recently new records for the highest temperatures recorded in the Antarctic Region, as part of continuing efforts to expand a database of extreme weather and climate conditions.

The highest temperature for the Antarctica Region (all land and ice south of 60 degrees south) of 19.8°C was observed on 30 January 1982 on Signy Island. The highest temperature for the Antarctic continent (the main continental landmass and adjoining islands) is 17.5°C, recorded on 24 March 2015 near the Argentine Base Esperanza at the northern tip of the Antarctic Peninsula. The highest temperature for the Antarctic Plateau (at or above 2,500 metres) was the observation of -7°C made on 28 December 1980 at an Automatic Weather Station site D-80 inland of the Adélie Coast.

Locations of the three high-temperature extreme stations (Signy, Esperanza, and D-80) are show. The area of the Antarctic region refers to all lands and ice south of 60°S. Also depicted is the 2500-meter elevation contour. (Credit: WMO)
Locations of the three high-temperature extreme stations (Signy, Esperanza, and D-80) are show. The area of the Antarctic region refers to all lands and ice south of 60°S. Also depicted is the 2500-meter elevation contour. (Credit: WMO)

Professor Renwick said the verification of these Antarctic extremes helps increase understanding about the Antarctic’s climate. “Knowledge and verification of such extremes is important in the study of weather patterns, naturally occurring climate variability and human-induced climate change at global and regional scales. All research on how the climate is changing is built upon high-quality records of weather and climate observations.” “These newly defined records give the international community a benchmark for comparison with future observations in a changing climate.”

The CCl committee consisted of polar science and climate experts from Argentina, Spain, Morocco, New Zealand, the United Kingdom and the United States. Full details of the assessment can be found in the online issue of Eos: Earth and Space Science News of the American Geophysical Union.

Source: Victoria University of Wellington