Intercomparison of surface heat transfer near the Arctic marginal ice zone for multiple reanalyses: A case study of September 2009

Abstract

This study evaluated surface heat fluxes in reanalyses (ERAInterim, JCDAS, and NCEP/NCAR) at the marginal ice zone during September 2009, a month in which intensive radiosonde soundings were performed during an Arctic cruise by the Japanese R/V Mirai. Two surface conditions are compared: very new ice cover during a period of low temperature and ice-free conditions. ERA-Interim reproduces the observed temperature profiles well because the turbulent heat fluxes are realistic, due to the explicit treatment of the ice concentration. With the relatively simplified treatment in JCDAS, the temperature is significantly underestimated (overestimated) in the quasi-ice-covered (ice-free) area. Although NCEP/NCAR has characteristics between ERA-Interim and JCDAS, the satellite-derived sea surface temperature (SST) distribution near the ice edge efficiently controls the heat fluxes.