Land Use and Climate Change

Although the presence of greenhouse gases in the atmosphere is the best known impact of human activity on climate change, variations in land use and surface cover may be of equal importance. In his Perspective, Pielke discusses results reported in the same issue by Feddema et al. in which changes in land cover--for example, from agricultural development--were included in climate simulations. One result of the simulation is that conversion of forest to agriculture in the model in the Amazon region leads to local temperature increases comparable to that simulated as being due to the radiative effect of the addition of carbon dioxide into the atmosphere. According to Pielke, the calculations suggest that all…