Integration of albedo effects caused by land use change into the climate balance: Should we still account in greenhouse gas units?

Due to impacts of albedo on climate change, benefits of afforestation/reforestation regimes are under debate. In this paper we investigate how to incorporate albedo changes in a carbon accounting tool to show the net effect of land use change on the climate. Using a study area in southern Europe, albedo and carbon sequestration modelling results are linked to determine the combined radiative forcing balance. The results show that under specific circumstances afforestation/reforestation measures may not automatically have positive impacts in a global warming context because the cooling effect of most of the carbon sequestered is neutralized by the warming effect of albedo changes. However, sensitivity analyses lead to the conclusion that improved albedo data from satellite images (MODIS) could influence and enhance outputs significantly. The paper points out that accounting based exclusively on GHG units does not, in the case of land use change, reflect the entire picture. It is highly recommended that in future global warming impacts of land use systems and biogenic products (e.g. solid biomass, liquid biofuels) should be studied using life cycle assessments (LCA) and should include these additional—non-GHG effects—on climate change.