The thick, wet forests of the Pacific Northwest are the carbon storage powerhouses of the U.S. -- in fact, they store more than 1-1/2 times as much carbon as the entire amount of carbon dioxide burned in fossil fuels throughout the country each year, a new study shows.

Two analysts for the Wilderness Society looked at data compiled by the U.S. Forest Service and identified 10 national forests, from the Tongass in southeast Alaska to the Siskiyou in southern Oregon, that together store about 9.8 billion metric tons of carbon on a total of 19 million acres.

By absorbing carbon dioxide, forests accumulate and store carbon in trees, roots and soil -- a valuable depository for greenhouse gases that, if released into the atmosphere, might contribute to climate change.

"To get a better idea of how much carbon this really is, we could compare it to the CO2 equivalent contained in the fossil fuels burned n the U.S. each year, about 5.8 billion metric tons," said Ann Ingerson, an economist for the Wilderness Society who co-authored the analysis with Mike Anderson, a senior resource analyst at the organization.