Super-size deposits of frozen carbon threat to climate change

The vast amount of carbon stored in the arctic and boreal regions of the world is more than double that previously estimated, according to a study published this week.

The amount of carbon in frozen soils, sediments and river deltas (permafrost) raises new concerns over the role of the northern regions as future sources of greenhouse gases.

“We now estimate the deposits contain over 1.5 trillion tons of frozen carbon, about twice as much carbon as contained in the atmosphere”, said Dr. Charles Tarnocai, Agriculture and Agri-Food Canada, Ottawa, and lead author

…Carbon deposits frozen thousands of years ago can easily break down when permafrost thaws releasing greenhouse gases to the atmosphere, according to another recent study by some of the same authors.

“Radioactive carbon dating shows that most of the carbon dioxide currently emitted by thawing soils in Alaska was formed and frozen thousands of years ago. The carbon dating demonstrates how easily carbon decomposes when soils thaw under warmer conditions,” said Professor Ted Schuur, University of Florida and co-author of the paper.

EurekAlert