Nature 475, 489–492 (2011)

Arctic tundra soils can contain thick deposits of organic material, often hundreds to thousands of years old, which store large quantities of carbon. Fire frequency and extent is increasing as the climate warms, making quantification of the magnitude of carbon released by these fires an important research goal.

Michelle Mack, of the Department of Biology at the University of Florida, and co-workers measured the carbon loss from a 2007 Alaskan wildfire — the largest on record for Arctic tundra. Based on these measurements they estimated the magnitude of ecosystem carbon released to the atmosphere across the entire 1,039 km2 fire scar.

Results indicate that about 2.1 Tg of carbon was lost to the atmosphere by the fire — a quantity similar to the net amount of carbon sequestered each year across the entire Arctic tundra. These results show the importance of fire disturbance on the carbon balance of the tundra, demonstrating a mechanism of climate change amplification.