Cool rainforests store more carbon

visto en washingtonpost.com

By Juliet Eilperin

Cool rainforests store more carbon per acre than tropical rainforests, according to a new book that synthesizes the work of 30 international scientists, a finding that could shift the way policymakers approach climate policy.

"Temperate and Boreal Rainforests of the World: Ecology and Conservation," published by Island Press, documents that in 2007 the 250 million acres of temperate and high-latitude forests stored 196 gigatons of carbon--the equivalent of six times the amount of carbon dioxide humans emit each year by burning fossil fuels.

With the world's climate negotiators poised to meet in United Nations-sponsored talks in Cancun at the end of the month, the book's editor said policymakers need to focus on "the world's forgotten rainforests." Conservation groups and world leaders have traditionally devoted their efforts to preserving tropical forests as carbon sinks, because in addition to curbing warming they host an array of species and give developing countries a financial incentive for cutting greenhouse gas emissions.

Tropical rainforests get between 60 and 160 inches of rain a year; temperate and boreal forests receive between 40 and 100 inches of rain annually but stay much cooler, with average annual temperatures of between 43 and 52 degrees Fahrenheit. Cool rainforests are found in 10 regions of the world, including America's Pacific Northwest; inland British Columbia and parts of Idaho and Montana; Eastern Russia and Southern Siberia; and Chile and Argentina.

"In some regions, like portions of Europe, nearly all rainforests are gone while others are headed in that direction if we don't act soon," said Dominick DellaSala, chief scientist and president of the Geos Institute in Ashland, Ore. "Decades of logging has created a national ecological debt crisis that is being passed on to future generations from which we are borrowing on their biological inheritance."

These temperate and boreal forests store carbon in the massive trunks of their trees, as well as in their dense soil and foliage. Old-growth temperate forests such as some in the U.S. and Australia, DellaSalla said, store more carbon per acre than any other kind of forest in the world. Ten percent of the world's temperate forests are in the Pacific Northwest and Alaska, while another 25 percent are along the coastline of Canada's British Columbia.

America's cool rainforests are just a fraction of their historic size: between 15-20 percent of old-growth rainforests remain in the Pacific Northwest, and less than 4 percent of the region's coastal redwoods still exist.