Greenhouse Gases Rise to Record Levels in Atmosphere, WMO Says

Concentrations in the atmosphere of the three main gases blamed for global warming all rose in 2011 to their highest since records began, the United Nations said.

Carbon dioxide, responsible for about 80 percent of the global warming effect of greenhouse gases, gained 0.51 percent to 390.9 parts per million molecules of air, the UN’s World Meteorological Organization said today in an e-mailed bulletin. The methane concentration increased 0.28 percent and the nitrous oxide level rose 0.31 percent.