Sea-Ice Melt-Pond Fraction as Determined from Low Level Aerial Photographs

Abstract

Surface melt features on Arctic sea ice contribute greatly to variations in surface energy absorption and exchange. This factor, when coupled with the spatial variability of melt-pond fractional coverage emphasizes the importance of calculating the rate at which the snow cover to melt-pond proportional area changes. The small area of many melt features, especially in the early spring, demand high resolution imagery to accurately determine melt-pond coverage. This study utilizes a time series of low level photographic infrared images collected from a tethered balloon to quantify the change in melt-pond fractional cover during the spring transitional period. The data were gathered as a component of the Seasonal Sea Ice Monitoring and Modelling Site (SIMMS) field experiment for 1995, conducted near Resolute, NWT, in the Canadian Arctic Archipelago. Analysis of the imagery indicates a linear growth rate of melt-pond coverage to a maximum ponding of just over 50%. Incorporation of microclimatic variables collected during SIMMS'95 reveals triggers to the onset of pond development. It is important to develop methods to characterize the evolution of melt-feature area as thermodynamic sea-ice models have shown sensitivity to variables associated with surface ponding.