Permafrost and Periglacial Processes

Decadal changes in permafrost distribution on the Qinghai-Tibet Plateau (QTP) over the past 50 years (1960–2009) were simulated with a response model that uses data from a digital elevation model, mean annual air temperature (MAAT) and the vertical lapse rate of temperature. Compared with published maps of permafrost distribution, the accuracy of the simulated results is about 85 per cent. The simulation results show: (1) with the continuously rising MAAT over the past 50 years, the simulated areas of permafrost on the QTP have continuously decreased; (2) through areal statistics, the simulated areas of permafrost were 1.60 × 106 km2, 1.49 × 106 km2, 1.45 × 106 km2, 1.36 × 106 km2 and 1.27 × 106 km2, respectively, in the 1960s, 1970s, 1980s, 1990s and 2000s; and (3) the rate of permafrost loss has accelerated since the 1980s, and the total area of degraded permafrost is about 3.3 × 105 km2, which accounts for about one-fifth of the total area of permafrost in the 1960s. Copyright © 2012 John Wiley & Sons, Ltd.