Abstract
The most comprehensive large-scale characterization of the global sea ice cover so far has been provided by satellite passive microwave data. The energy exchange between ocean and atmosphere over ice-covered areas is largely influenced by the occurrence of openings in the ice pack and of newly and young ice. Thus, accurate retrieval of thin sea ice areas and their ice concentrations from these data is quite important. NASA Team Thin Ice algorithm was proposed for mapping the distribution of new, young and first-year sea ice and calculating ice concentrations in seasonal sea ice zones by Cavalieri (1994). In this paper, a new algorithm is proposed for mapping the global thin sea ice area in freezing season. It utilizes two sea ice concentrations and two mixed ratios of sea ice types derived from NASA Team Standard algorithm (using global tie points) and NASA Team Thin Ice algorithm (using thin ice tie points). The brightness temperatures of 100% sea ice concentrations are calculated using the sea ice concentrations and the mixed ratios of sea ice types from the two algorithms respectively. The thin sea ice area is detected by comparing the brightness temperatures of 100% sea ice concentrations derived from the both algorithms.
