U.S. researchers say satellite data shows arctic sea ice is melting at a rate that could reach a record low in percentage of coverage by the end of the month. With about four weeks still remaining in the melt season, sea ice coverage is likely to fall below the previous record low seen in 2007, the U.S. National Snow and Ice Data Center reported. Arctic sea ice extent was 1.97 million square miles on August 13, 1.04 million square miles below the 1979 to 2000 average coverage for the date, researchers said. The average rate of ice loss since late June has been rapid at just over 38,000 square miles per day, the center reported, with ongoing melting expected through mid- to late September. Ice data was obtained by Cryosat, a radar satellite launched in 2010 and operated by the European Space Agency to monitor changes in the thickness and shape of polar ice.