Melt ponds on sea ice in the Canadian Archipelago 1. Variability in morphological and radiative properties

The morphological and radiative properties of melt ponds on first-year sea ice (FYI) were investigated during the summer of 1997 in the Canadian Archi pelago as part of the Collaborative-Interdisciplinary Cryospheric Experimen t (C-ICE) near Resolute Bay, Nunavut. In this paper we (1) describe a class ification technique used to identify surface cover types from airborne vide ography during the melt pond season, (2) use the classification results to examine the fractional coverage of surface types and morphological characte ristics of melt ponds, and (3) provide an estimate of the integrated shortw ave albedo of this surface. Cluster analysis on the videography data identi fied four distinct surface cover types during the summer melt season: snow, saturated snow, light-colored melt ponds, and dark-colored melt ponds. Mel t pond coverage was found to be highly variable over our study area. We fou nd that pond sizes tended to be twice as large in areas of high melt pond d ensity compared to ponds in areas of low pond density owing to their interc onnective nature, Video data also identified an elongated melt pond morphol ogy pattern over the smoothest FYI within our study region. A derived estim ate of the integrated shortwave albedo was strongly related to the fraction al cover of snow on the surface (R-2 = 0.86). An analysis of combined fract ional coverage of light and dark melt ponds from two aerial survey dates (J ulian Days 181 and 184) revealed an aerial increase in melt ponds of simila r to 10.3%.