An examination of the relation between the spring period evolution of the scattering coefficient (σ) and radiative fluxes over Jandfast sea-ice

In this work we examine the seasonal co-evolution of: the microwave scattering coefficient (σ°) as observed with ERS-l; the radiative components of the surface energy balance; and the physical and electrical properties of the snow/ sea-ice system. We conduct three sets of hypothesis tests designed to illuminate specific aspects of this co-evolution. In Hypothesis Set I we contrasted components of the observed radiation balance between multiyear (MYI) and first-year (FYI) ice sites. We found that the surface skin temperature (Ts) and the longwave flux (L*) could be considered statistically indistinguishable between MYI and FYI for conditions experienced during the 1993 Seasonal Sea Ice Monitoring and Modelling Site (SIMMS'93) experiment. The shortwave flux (K*) and net allwave flux (Q*) were however statistically distinguishable between the MYI and FYI sites. In Hypothesis Set 2 we investigated the nature of the seasonal evolution in σ° for six dilTerent ice sites (three multiyear and three first-year types). We showed that multiyear ice forms have a particular pattern in their seasonal behaviour of a" which is distinct from the seasonal pattern of σ° for first-year forms and that the time series of a" could be used in ice type discrimination. In Hypothesis Set 3 we conducted a multivariate analysis to explore the relationship between components of the radiation balance and the seasonal evolution of σ°, We found that of all the radiation variables tested, K* explained a statistically significant portion of the observed seasonal variation in a? at the FYI site but not at the MYI site.