Thermal conductivity of porous ice in hailstone shells

• Published in: Journal of Glaciology
• Main Authors: Zheng, Guoguang, List, Roland
• Format: Article in Journal/Newspaper
• Language: English
• Published: Cambridge University Press (CUP) 1996
• Subjects: Earth-Surface Processes; Journal of Glaciology
• Online Access: http://dx.doi.org/10.1017/s0022143000004056; https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143000004056

Abstract The thermal conductivity and diffusivity of porous ice accreted on spherical and spheroidal hailstone models were measured over a density range of 620–915 kg m −3 . By scanning the evolving surface temperature distributions during cooling in a cold airflow the thermal conductivity was varied in iterative fashion until the internal heat flux produced the correct surface temperature distribution. The results indicate a linear dependence of the thermal conductivity, k i , and diffusivity, α i , on density. For example, lowering the density by 10% lowers k i by 15%. Within the range of cloud conditions, the density variations affect the thermal parameters more than temperature does. The results also indicate a continuous decrease of the thermal conductivity from bulk ice via consolidated porous ice to loosely packed snow.