Simulating global and local surface temperature changes due to Holocene anthropogenic land cover change



Surface albedo changes from anthropogenic land cover change (ALCC) represent the second largest negative radiative forcing behind aerosol during the industrial era. Using a new reconstruction of ALCC during the Holocene era by Kaplan et al. (2011), we quantify the local and global temperature response induced by Holocene ALCC in the Community Climate System Model, version 4. We find that Holocene ALCC causes a global cooling of 0.17°C due to the biogeophysical effects of land-atmosphere exchange of momentum, moisture, and radiative and heat fluxes. On the global scale, the biogeochemical effects of Holocene ALCC from carbon emissions dominate the biogeophysical effects by causing 0.9°C global warming. The net effects of Holocene ALCC amount to a global warming of 0.73°C during the preindustrial era, which is comparable to the ~0.8°C warming during industrial times. On local to regional scales, such as parts of Europe, North America, and Asia, the biogeophysical effects of Holocene ALCC are significant and comparable to the biogeochemical effect.