This is an excerpt from EERE Network News, a weekly electronic newsletter.

April 30, 2008

Researchers Note Rising Levels of Atmospheric Greenhouse Gases

The National Oceanic and Atmospheric Administration (NOAA) reported on April 23 that the levels of carbon dioxide and methane in Earth's atmosphere increased significantly in 2007. Global levels of carbon dioxide in the atmosphere increased by 0.6%, or 19 billion tons. More troubling is a 27-million-ton increase in methane, which hasn't increased since 1998. NOAA researchers attribute the methane increase to rapid industrialization in Asia and rising emissions from wetlands in the Arctic and tropics, but they're not quite sure which sources are causing the sudden increase. But so far, the effect remains relatively small: even accounting for methane being 25 times more powerful as a greenhouse gas than carbon dioxide, last year's rise in methane levels would be equal to about 675 million tons of carbon dioxide. Last year's rise in carbon dioxide levels was 28 times larger. See the NOAA press release.