Antarctic sea ice reaches record low, a sign of climate change impacts. Scientists outline possible causes.
Analysis of the latest satellite imagery shows that sea ice around Antarctica has reached a 40-year low. According to the National Snow and Ice Data Center at the University of Colorado Boulder, as of February 22, the ice cover around the Antarctic coast was approximately 1.94 million square kilometers, breaking the previous record low of 2.11 million square kilometers set in early March 2017. Antarctic sea ice reaches a new low; warming oceans are only one factor. Marilyn N. Raphael, a geography professor at the University of California, Los Angeles, who studies Antarctic sea ice, said warming ocean temperatures may be one factor, "but we will be working hard in the coming months to identify other factors." Antarctic sea ice extent varies significantly from year to year, but has averaged very small increases since satellite observations began in the late 1970s. In contrast, the Arctic, which is warming three times faster than other regions, has seen its sea ice extent decrease by more than 10% per decade during the same period. The two regions face starkly different situations. The North Pole and the Polar Circle cover the Arctic Ocean and are surrounded by land. In the Southern Hemisphere, the South Pole and the Arctic Circle are covered by the Antarctic continent and surrounded by the Southern Ocean. Although the rapid warming of the Arctic is the main reason for the shrinking of local sea ice, the impact of climate change on Antarctic sea ice is not so clear. Is global warming causing the reduction of Antarctic sea ice? Scholars: The relationship between the two is not yet clear.