CryoVEx2014: Observations of Arctic Snow and Sea Ice Properties for Validation of Cryosat and Icebridge Retrievals

Abstract:

The European Space Agency’s (ESA) CryoSat mission and NASA’s airborne Operation IceBridge observe large-scale, regional and temporal changes of sea ice thickness in the Arctic by means of radar and laser altimetry. Unfortunately, snow thickness variability and scaling issues at all scales from meters to hundreds of kilometers remain some of the main sources of error for altimetric sea ice thickness retrievals. To address this gap, extensive coincident airborne and in-situ ice and snow measurements were performed as part of the CryoSat Validation Experiment in March and April 2014 (CryoVEx 2014). In-situ ice and snow thickness measurements were performed at four locations representative of various Arctic ice and snow conditions. Two sites were located in first year ice near Barrow, Alaska; one was in the Canadian Beaufort Sea’s thin multiyear ice; and one was in thick multiyear ice situated north of Greenland. All four sites were overflown by a number of aircraft equipped with various ice and snow thickness sensors that captured ice and snow property variations. At our field sites, ice thickness, surface roughness, and snow thickness measurements were performed along 2 km transects. Centered on these transects were 60 m x 400 m intensive snow measurement grids with 5 m x 5 m point spacings and nested 60 m x 100 m grids with 1 m x 1 m point spacings. These snow thickness measurements were acquired to study the two-dimensional variability and to provide information on scales comparable to or exceeding the footprint sizes of airborne snow thickness radars operated by NASA and ESA. Here we present results of these snow and ice thickness measurements to shed light on the large- and small-scale spatial variability of these properties across the Arctic. In addition, we present first results from initial comparisons with the airborne and satellite snow and ice thickness retrievals.