Radiative transfer simulations link boreal forest structure and shortwave albedo

Vegetation cover and land-use changes induced by human activities have changed the global surface albedo, or the extent to which incoming solar radiation is reflected back to the atmosphere. Forest albedo is a critical variable affecting the Earth's climate, and is still among the main uncertainties of the radiation budget in climate modelling. A synthesis of current research results clearly indicates a need for more reliable quantitative predictions of the effect of forest structure on the global albedo. This paper reports a case study on the application of a forest radiative transfer model in shortwave albedo simulations: we simulate the blue-sky and black-sky albedos of coniferous stands in Finland, and link forest albedo to stand structure and management practices. Our results indicate that boreal forest albedo decreases as the stands become older and as their standing stock increases, and that regular thinning procedures reduce stand summer albedo of coniferous forests.