Aircraft measurements of up- and downward irradiances over Arctic sea ice during the ACLOUD campaign@en

During the ACLOUD (Arctic CLoud Observations Using airborne measurements during polar Day ) campaign in May / June 2017 spectral up- and downward irradiances were measured over the Arctic sea ice using the Spectral Modular Airborne Radiation measurement sysTem (SMART-Albedometer). The data set gives time series of irradiances measured along the flight path for three different wavelengths (555 nm, 645 nm, and 1640 nm) on different days and for different illumination conditions. The surface albedo can be directly calculated from the up- and downward irradiances. From these data set a temporal change of the sea ice albedo and a dependence on the illumination condition can be observed.