Levels of the main greenhouse gas in the atmosphere have risen to new highs in 2010 despite an economic slowdown in many nations that braked industrial output, data showed on Monday.

Carbon dioxide, measured at Norway’s Zeppelin station on the Arctic Svalbard archipelago, rose to a median 393.71 parts per million of the atmosphere in the first two weeks of March from 393.17 in the same period of 2009, extending years of gains.