ABSTRACT

This chapter examines soil carbon (C) in permafrost-dominated boreal forests and summarizes the estimates for climate change in the northern latitudes, the projected reduction in permafrost area for North America, and estimates of the rate of permafrost loss and consequent increase in the active layer. It examines the timescale of these changes, the sensitivity of permafrost soils, and the fate of sequestered carbon to interannual changes in air temperatures. The thickness of the active layer has likely increased across much of the North American high latitudes. The boreal forests and peatlands, because of their large carbon stores, are expected to face the largest impact and earliest effects of climate change. In turn, this region will have the largest feedback to the global system. Potential climate-change effects are substantial. Temperature change will increase the northward migration of tree line into the arctic tundra and the distribution of deciduous forest to the south.