Accession Number : AD0765938

Title :   The Decay of an Annual Cover of Sea Ice,

Corporate Author : MCGILL UNIV MONTREAL (QUEBEC) DEPT OF PHYSICS

Personal Author(s) : Langleben,M. P.

Report Date : 25 OCT 1971

Pagination or Media Count : 9

Abstract : The report discusses the melting of sea ice during the Arctic summer by thermal interaction with the surrounding water and derives an expression which indicates that the proportion of open water increases exponentially with time until total ice-free conditions result. The equation predicts that the time required for complete decay of the ice cover after initial break-up is greater than one month and more likely as long as two months for representative values of incident shortwave radiation and initial ice thickness upon break-up. It is unlikely that above-freezing temperatures persist for this length of time. To explain the observed complete disintegration of the annual ice cover in many sheltered areas of the Arctic, a modified model of the thermal decay process has been introduced and takes into account the influence of radiation absorbed by the ice. Considerable reduction in the time required for complete decay, generally by about a factor of 2 if an albedo of 0.4 is assumed for the ice surface, is obtained. (Modified author abstract)

Descriptors :   (*SEA ICE, MELTING), (*ARCTIC REGIONS, SEA ICE), THERMAL RADIATION, INTERACTIONS, THICKNESS, MATHEMATICAL PREDICTION, FREEZING

Subject Categories : Snow, Ice and Permafrost

Distribution Statement : APPROVED FOR PUBLIC RELEASE