Cloud filtering with MERIS and AATSR for melt pond detection on Arctic sea ice

Melt ponds cover up to 50% of Arctic summer sea ice and strongly affect the local radiative balance. However, they are currently poorly represented in circulation models. One of the reasons is the lack of reliable large-scale observations. A challenge encountered during melt pond retrieval from optical satellite observations is the filtering of cloud which in the visible range of spectrum look similarly bright as the sea ice surface. Here we demonstrate the influence of undetected cloud on the melt pond retrieval and suggest a masking procedure based on a Bayesian classifier trained using coincident infrared observations of AATSR. The AATSR swath only covers the central half of the MERIS swath but the masking procedure extends the filtering scheme to the outer parts of the MERIS swath so that the full swath can be used for melt pond retrieval.