Arctic tundra heating rapidly, releasing greenhouse gases
By David Ljunggren OTTAWA (Reuters) – Regions of Arctic tundra around the world are heating up very rapidly, releasing more greenhouse gases than predicted and boosting the process of global warming, a leading expert said on Wednesday. Professor Greg Henry of the University of British Columbia also said higher temperatures meant larger plants were starting to spread across the tundra, which is usually covered by small shrubs, grasses and lichen. The thicker plant cover means the region is getting darker and absorbing more heat. He said tundra covers about 15 percent of the world’s surface and makes up around 30 percent of Canadian territory. Henry, who has been working in the Arctic since the early 1980s, said he had measured “a very substantial change” in the tundra over the last three decades, citing greater emissions and plant growth. Since 1970, he said, temperatures in the tundra region had risen by 1 degree Celsius per decade — equal to the highest rates of warming found anywhere on the planet. “We’re finding that the tundra is actually giving off a lot more nitrous oxide and methane than anyone had thought before,” Henry told reporters on a conference call from Resolute in the northern Canadian territory of Nunavut. … Some scientists also fear that as the permafrost in the Arctic melts, it will release vast amounts of carbon and methane into the atmosphere.
