America's Forest Carbon Sink Is Shrinking, Government Report Says

America's forests seem likely to scrub much less carbon dioxide out of the atmosphere in the future compared to the last few decades, according to a government report submitted last week to the United Nations.

Although the timing and extent of the shift is hard to pin down, the expected change could make it harder for the United States to meet its commitments to control CO2, the principal greenhouse gas that is warming the planet.

In recent years, the nation's forests have been growing.  The density of their trees has increased as growth exceeded harvests, and there have been small annual increases in the area of forested land.  But the beneficial trends are expected to slow, and ultimately to reverse, the report warned.

"In the long term, U.S. forest carbon stocks are likely to accumulate at a slower rate, and eventually may decline as a result of forestland conversion and changes in growth related to climate change and other disturbances," the report said.

"U.S. forests are unlikely to continue historical trends of sequestering additional carbon stocks in the future under current policy conditions," it added.

America's Forest Carbon Sink Is Shrinking, Government Report Says