Rain follows logging in the Amazon? Results from CAM3–CLM3

Abstract

The impact of logging on precipitation in the Amazon region is investigated based on numerical experiments using the community atmosphere model version 3 coupled with the community land surface model version 3 (CAM3–CLM3). Three different representations of logging are examined, ranging from selective logging, to partial deforestation, to clear cut. Precipitation increases in response to modest selective logging, and decreases as the severity of logging progresses to partial deforestation and clear cut. Further experiments indicate that the increase of precipitation is mostly due to the decrease of surface albedo following selective logging, resulting from a low contrast between bare soil albedo and vegetation optical properties (i.e., leaf reflectance) in CLM3. This study demonstrates the complexity of representing land cover changes in climate models, and underlines the importance of accuracy in albedo measurement from satellite remote sensing.