Abstract:

Some mass balance characteristics on small dome of Collins Ice Cap were analyzed according to a full year measurement data of mass balance on small dome of the ice cap in 1991/1992.The small dome belongs to the type of glacial mass supplied in cold season,periods of accumulation and ablation were distinguished clearly.Although the range of the height of small dome is not large,the melting period at terminal was two months longer than that at the top; Amount of ablation in warm season decreased rapidly with increase of the height.Affected mainly by the undulation of glacial surface, accumulation in cold season varied remarkably.Mass balance at SDS section in 1991/1992 was a weak positive balance year with a mass balance difference of 163 mm,altitude of equilibrium line was 140m,which was 20m lower than that of dynamic equilibrium line.Mass balance characteristics showed larger mass balance gradient,lower mass balance level and smaller stability coefficient,which reflected the distinctive property of glacial mass balance under the condition of subpolar maritime climate.