Reuters: Arctic permafrost that is thawing due to global warming is releasing greenhouse gases, further compounding the problem of climate change, according to a study released on Thursday. As the permafrost thaws, changes in the way its soil microbes function and the soil carbon decomposes add to the emissions of carbon dioxide and methane into the atmosphere, according to the study by U.S. and Chinese scientists. Carbon dioxide and methane are the main greenhouse gases that trap heat and contribute to...