EDMONTON, Alberta, March 15 (UPI) -- Canadian researchers say the impact of peatlands on prehistoric climate change has been overestimated but they could affect the current global warming trend.
University of Alberta researchers say northern peatlands, a boggy mixture of dead organic material and water covering more than 1.5 million square miles, sequester carbon in the form of carbon dioxide from the atmosphere. As old peat is buried and begins to decompose it emits large amounts of methane, a potent greenhouse gas, a university release said Tuesday.
The largest northern peatlands are located in the subarctic regions of Canada and Russia.
University researchers studied radiocarbon dates of ancient peatlands to examine how they first colonized northern regions at the end of the last ice age, a period of rapid global warming. Atmospheric carbon dioxide and methane rose dramatically 10,000 years ago at the end of the last ice age, and scientists believed that northern peatlands were a large, if not the principle, source of the dramatic increase in atmospheric methane.
But the research showed peatlands did not colonize the north until 500 to 1,000 years after the abrupt increases in atmospheric methane, suggesting other sources, such as tropical wetlands, were the main cause.
The researchers said their findings show how easily huge, complex areas of the planet and their effect on climate can be misunderstood.