Spectral and integrated albedo (photosynthetically active radiation and total) of the forested landscape surrounding the SMEAR-Estonia research station is estimated using airborne measurements of reflectance spectra and MODIS land products. Airborne reflectance measurements were carried out during the stable period of phenology in the middle of growing season in 2006-2015. MODIS Collection 5 products are available since autumn 2006. The directional canopy reflectance models FRT and ACRM are used for the integration of directional reflected radiance over hemisphere. Spectral black sky albedo is found for 18 visible-near infrared spectral bands which correspond to the Mode 3 bands of the Proba/CHRIS imaging spectrometer. Year-to-year variations of albedo are small, therefore, the mean albedo values are provided which could be used in the studies of energy fluxes and net primary production at the test site. MODIS estimates of albedo are systematically higher and more variable than estimates using airborne spectral measurements.

Keywords: Forest albedo, MODIS albedo product, Airborne measurements.