Weekly Polar-Gridded Aquarius Products and their Applications over the Cryosphere

Abstract:

Passive and active microwave observations at 1.413 GHz (L band) from the Aquarius/SAC-D mission offer new capabilities to study and to monitor the Earth's polar regions. To facilitate the access and use of the Aquarius data over the polar regions, and to move forward our understanding of the L-band observations of ice sheet, sea ice, frozen soil, and high-latitude oceans, three weekly polar-gridded products were produced. Aquarius data recorded at northern and southern latitudes higher than 50 degrees were averaged and gridded into weekly products of: a) Brightness Temperature (TB); b) Normalized Radar Cross Section (NRCS); and c) Sea Surface Salinity (SSS). Additionally, each grid cell contains sea ice fraction and the standard deviation of TB, NRCS, and SSS along with the number of footprint observations/retrievals obtained during the seven-day cycle. These products are distributed on the version 2.0 of the Equal-Area Scalable Earth (EASE2.0) grid, with a grid cell resolution of 36 km. Since July 2014, the US National Snow and Ice Data Center archives and distributes the products, starting in August 2011 with the first Aquarius observations. The data sets are updated on a monthly basis following the release schedule of the Level 2 data sets. We present these products, which may be used to analyze the spatio-temporal variations of the deep penetration L-band observations over the Greenland and Antarctic ice sheets, sea ice in both hemispheres, and soil freeze/thaw cycles.