The Impact of Climate Change on Canadian Peatlands

Abstract

Peatlands cover 12% (1.136 million km2) of the land area of Canada, with perennially frozen peatlands covering 37% of this area and peatlands of the Boreal and Subarctic regions covering 97%. In total, these peatlands contain approximately 147 Gt of soil organic carbon, which is about 56% of the organic carbon stored in all Canadian soils. Climate change predictions suggest that the average annual air temperature in northern Canada will increase 3–5°C by the end of this century. A peatland sensitivity model was used to determine the effect of climate warming on these peatlands. This model predicts that approximately 60% of the area and 56% of the organic carbon mass in all Canadian peatlands will be severely to extremely severely affected by climate change. Although peatlands were affected by climate change in the past, the changes occurred at a slower rate than is predicted for the current change of climate. This accelerated rate of climate change will result in serious degradation of perennially frozen peatlands in the Subarctic and Boreal regions and severe drying of peatlands in the southern portions of the Boreal Region. As a result of these changes, large amounts of carbon in the forms of carbon dioxide (CO2) and methane (CH4) will be released into the atmosphere from these peatlands. This will further accelerate climate warming.