Accuracy assessment of MODIS daily snow albedo retrievals with in situ measurements in Karasu basin, Turkey

Abstract

Over the ablation period of 2004, daily snow albedo values retrieved from the moderate-resolution imaging spectroradiometer (MODIS) Terra were compared with ground-based albedo measurements. Two data sets are used for this study. The first data set is from two automatic weather stations (AWS) located at fixed points in Karasu basin in eastern Turkey. This provided the temporal assessment of MODIS daily snow albedo values. The second data set, consisting of 19 observation points randomly distributed around one of the AWS sites, enables the spatial variability assessment of MODIS albedo retrievals. Both MODIS and in situ albedo observations were aggregated in a geographic information system for further analysis. Generally, MODIS albedo values were within 10% of the in situ values. Reductions in albedo values were observed both in MODIS and field observations as snow depth decreased and snow water equivalent increased. Copyright (c) 2006 John Wiley & Sons, Ltd.