Credit: ©istockphoto/Terrance Emerson

Research suggests that biofuel use can lower greenhouse-gas emissions compared with conventional fossil fuels and contribute to the mitigation of global climate change. Now, a study shows that biofuels can also cool the local climate, if planted on land traditionally used for growing agricultural crops.

Matei Georgescu from the Center for Environmental Fluid Dynamics, Arizona State University, Tempe, USA and co-workers show that large-scale plantations of perennial biofuel crops, such as the grass Miscanthus, can directly cool the local climate by increasing evapotranspiration and albedo — a measure of surface reflectivity1. Georgescu and colleagues modified the surface-vegetation properties in a regional climate model to represent that of perennial biofuel crops and analysed the potential outcome for the climate. Their model results indicate that the combined effects of altered evapotranspiration and albedo would result in cooling throughout the central US of nearly 0.9 °C.

This cooling could partially compensate for the expected warming from greenhouse-gas emissions over the next few decades, note the authors.