Climate Change Due to Anthropogenic Surface Albedo Modification

摘要

Using a statistical dynamic climate model with more realistic surface albedo changes than used in previous experiments, we have conducted a numerical experiment combining desertification of the Sahara and deforestation of the tropical rain forest. Over an area of 9 x 10 exp 6 km exp 2 at 20 exp 0 N the desert albedo was increased from 0.16 to 0.35 and over 7 x 10 exp 6 km exp 2 at the equator and 10 exp 0 S the rain forest albedo was increased from 0.07 to 0.16. While the most significant direct climatic responses were observed in the modified zones, high northern latitudes exhibited the greatest cooling through activation of the ice-albedo feedback process. In contrast to Sagan et al., this experiment suggests that anthropogenic modification of surface albedo over the past few thousand years has had an impact on global climate which is likely quite small and probably undetectable. (ERA citation 05:016554)