Measurements and Improved Parameterization of the Thermal Conductivity and Heat Flow through First-Year Sea Ice

University Of Alaska Fairbanks Campus, Fairbanks AK

Investigators

Abstract

This study will derive the thermal conductivity of first-year antarctic sea ice as a function of ice microstructure, temperature, temperature gradients, salinity, and other environmental parameters. Measurements will be carried out by freezing thermistor arrays into the fast ice of McMurdo Sound. The thermal conductivity of sea ice determines the magnitude of the heat flow through the ice, and hence the exchange of heat between the ocean and atmosphere, for a given ice temperature gradient. General circulation models (GCMs) and large-scale sea-ice models currently include overly simplistic parameterizations of the ice thermal conductivity, developed several decades ago, that are likely to contribute significantly to errors in estimating ice production rates. The results from this work will feed into improved parameterizations of sea ice parameters for collaboration with the Sea-Ice Model Intercomparison Project (SIMIP2) Team established under the auspices of the World Climate Research Program. The research will advance and improve: (1) our understanding of processes and parameters controlling heat transfer and thermal conductivity of first-year sea ice, (2) measurement techniques for the derivation of thermal conductivity and heat flow data from thermistor arrays, (3) our understanding of sea-ice processes and heat flow through the ice cover in the McMurdo Sound region, (4) parameterizations of thermal conductivity for use in large-scale and high-resolution one-dimensional simulations, and (5) the representation of first-year ice antarctic and arctic thermal properties in GCMs.