Integration of SMOS and ENVISAT ASAR data for sea ice change study

Observations of nearly 30 years show that Arctic sea ice is changing rapidly since the 21st century. The coverage as well as the thickness of sea ice decreased year by year, indicating that the ice condition is getting lighter. The Northeast passage is the connection of the North Atlantic and North Pacific. The Northeast passage is expected to be open as a trading channel in the near future, which will shorten the journey, greatly reducing the transport costs from East Asia to northern Europe. The suitable navigation time of Northeast passage varies greatly year by year, which is mainly dominated by the sea ice conditions among Russia's New Siberian Island, severnaya zemlya and mainland. In this study, we choose the ocean surface area near New Siberian Island and Vilkitskogo Strait near severnaya zemlya as study area. The sea ice thickness data in the area (from October 15th to March 31st of the second year, 2010-2012) inverted from SMOS (Soil Moisture and Ocean Salinity) brightness temperature are used to study the sea ice thickness change in the 3 years. ENVISAT ASAR data (2010-2012) were used to validate the accuracy of sea ice thickness inverted by brightness temperature of SMOS data, and also to study the spatio-temporal dynamic of sea ice. Preliminary results showed that: 1) The sea ice thickness has decreased in the area around New Siberian Island from 2012 to 2012, while the sea ice thickness of Vilkitskogo Strait near severnaya zemlya changes less. 2)As the most critical factor affectting navigation,sea ice thickness is of significant seasonal change. The freezing time in October is postponing. 3) The sea ice thickness data inverted by brightness temperature of SMOS data are more accurate in winter.