Accession Number:

ADA275162

Title:

On the Temperature Distribution Near a Cold Surface

Descriptive Note:

Corporate Author:

COLD REGIONS RESEARCH AND ENGINEERING LAB HANOVER NH

Personal Author(s):

Report Date:

1993-10-01

Pagination or Media Count:

29.0

Abstract:

Temperature profiles were taken during the 1991-92 season at an experimental site on CRRELs grounds however, they were rather limited because of the unusual lack of snowfall and the location of the site, which was small and had elevated sides especially in the direction of the prevailing wind. Nevertheless, some unusual features have been observed for the first time. The profiles show the existence of a double-reversal in temperature structure close to the snow surface when the snow temperature is much lower than its melting point, in contrast to a persistent raised maximum temperature over a melting snowpack. This indicates that the micro-heat transport process is complicated by the presence of a non-isothermal lower boundary. Over frozen or partially frozen ground without snow, and with air temperature either above or below the melting point of ice, a thin, nearly isothermal air layer on the order of 2 to 3 cm in thickness at varying heights was observed for the first time. With very few exceptions, in general, the temperature decreases as height increases, but the extent is less pronounced over a snow cover where conditions are nearly isothermal than over cold ground. On the basis of limited measurements, the overall temperature gradient over the bare ground is about twice that over snow- covered ground. Cold surfaces, Ice, Snow, Frozen ground, Micrometerology, Temperature profiles.

Subject Categories:

  • Snow, Ice and Permafrost
  • Thermodynamics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE