Sea Ice Characterization using Polarimetric GNSS-R from the SMAP-R Dataset

Sea ice is an important element in the climate change. Sea ice has been consistently reduced over summer months, causing the reduction of the reflective layer and facilitating the warming of the oceans. Monitoring sea ice layer parameters, such as extent, concentration, thickness and type, is very important towards understanding what is the impact of the sea ice variations into the climate change. The sensitivity of pseudo-polarimetric Global Navigation Satellite System - Reflectometry (GNSS-R) to the changes in the cryosphere is currently being investigated thanks to the availability of such measurements enabled by the Soil Moisture Active Passive (SMAP) mission's radar working on receive mode. The SMAP radar is now a bistatic radar instrument that measures the GPS signal after it reflects off the Earth surface in linear polarizations, both horizontal (H) and vertical (V). This configuration is known as hybrid compact polarimetry (HCP), and SMAP reflectometer (SMAP-R) is the first satellite instrument to implement it. SMAP-R polarimetric GNSS-R measurements add value for sea ice investigations.

We will present SMAP-R based retrieval algorithms for sea ice extent, concentration and sea ice type over the Arctic Sea during year 2018. We will use SMAP-R HCP GNSS-R measurements to compute Stokes parameters and child-Stokes parameters and link those to the mentioned sea ice geophysical parameters. Our retrievals will be validated against data products from other sensors, such as the National Snow and Ice Data Center (NSIDC) sea ice concentration product and the European Organization for the Exploitation of Meteorological Satellites (EUMETSAT) Ocean and Sea Ice Satellite Application Facilities (OSI SAF) sea ice type and sea ice extent products.