Sea-Ice and Snow-Cover Data Availability, Needs and Problems

Abstract

Various types of sea-ice and snow-cover data are required for operational purposes in real time, for engineering assessments of associated hazards and for regional to global-scale modeling of the climate system. Data on the primary characteristics of ice and snow (extent, depth or thickness, and ice concentration) are becoming available to meet many present types of modeling requirement but secondary properties such as snow-water content, ridging intensity, open-water fraction and ice drift are less readily available.Data for these major variables of snow and ice cover are considered with respect to problems encountered in obtaining and using digital information necessary for modern computer analyses. Such problems include the limitations of the basic observations (observational or sensor accuracy), the spatial and temporal resolution of different data sets, varying national practices of observing and reporting, and the problems of meshing data collected by different means and having spatial differences and temporal changes of observation time, site location, sensor system and resolution, etc. The relative reliability and climatic “information content” of some historical data sets are briefly examined and available digital data sets on modern global ice- and snow-cover conditions are described.