Summary: | Elevation-change-rate estimates from the two missions have been corrected for firn-air content changes. For grounded ice, they have been corrected for changes in the elevation of the bedrock under the ice sheet, and for floating ice, the hydrostatic relation has been used to convert elevation changes to thickness changes. We provide a set of grids that contains fully corrected but unsmoothed gridded data, from which our calculations of drainage-by-drainage mass change were derived, and a second set of smoothed grids that are intended for display purposes only. Each set of grids provides ice-sheet surface height and thickness change rate in meters of ice per year (m/yr). Full details of the processing and analysis of these data are provided in Smith et al., (2020, Science). Two sets of files are provided in geotif format: one unfiltered set, which are suitable for mass-balance integrations, and a filtered set that have been smoothed for display, which match figures 2 and 3 in Smith et. al, 2020. These data represent ice-column thickness-change-rate estimates based on data from NASA's ICESat and ICESat-2 satellites. These data aided the first estimates of ice-sheet mass change from these two missions, spanning the 16 years from 2003 to 2019, taking advantage of the high vertical and horizontal resolution of the two satellites' laser altimeters. NASA grant numbers: NNX15AE15G, NNX15AC80G, NNX16AM01G, NNX17AI03G. NASA Cryospheric Sciences and MEaSUREs programs.
|