DOINews: New Science Shows Carbon Storage Potential of U.S. Lands

U.S. Geological Survey scientists have found that the lower 48 states in the U.S. presently store 73 billion metric tons of carbon in soils and 17 billion metric tons in forests. This is equivalent to more than 50 years of America's current CO2 emissions from burning fossil fuels.

The national assessment of biologic carbon sequestration estimates there is the potential to store an additional 3-7 billion metric tons of carbon in forests, if agricultural lands were to be used for planting forests. This potential is equivalent to 2 to 4 years of America's current CO2 emissions from burning fossil fuels.

America's forests and soils currently absorb about 30 percent (0.5 billion metric tons of carbon) of the nation's fossil fuel emissions per year (1.6 billion metric tons of carbon). Enhancing the carbon storage capacity of America's and the world's ecosystems is an important tool to reduce carbon emissions and help ecosystems adapt to changing climate conditions.

“The tools the USGS is developing—and the technologies behind those tools—will be of great use to communities around the world that are making management decisions on carbon storage,” said USGS Director Marcia McNutt. “The USGS is conducting a national assessment of biologic carbon sequestration, as well as an assessment of ecosystem carbon and greenhouse gas fluxes, which will help determine how we can reduce atmospheric CO2 levels while preserving other ecological functions.”

To determine how much more carbon could be stored in forests and soils, USGS scientists analyzed maps that represent historical vegetation cover before human alterations, as well as maps of vegetation that might occur if there were no natural disturbances, such as fires, pests and drought. These maps were compared to maps of current vegetation and carbon storage.

The next phase of this work will assess the additional amount of carbon stored in Alaska's ecosystems, including its soils and forests.