A 3D map of englacial attenuation rate from radar reflections at Law Dome, East Antarctica

The East Antarctic Ice Sheet (EAIS) is the largest source of potential sea-level rise, containing some 19 m of sea-level equivalent. One of the well-investigated regions in East Antarctica is Law Dome, which is a small independent ice cap situated to the west of Totten Ice Shelf. The ice cap is slow-moving, has a low melt-rate at the surface and moderate wind speeds, making it a useful study site for our investigations. Radar data from Investigating the Cryospheric Evolution of the Central Antarctic Plate (ICECAP) project has good coverage over this area. A new method is proposed for the estimation of attenuation rate from radar data which is mathematically modeled as a constrained regularised l2 minimization problem. In the proposed method, only radar data is required and the englacial reflectors are automatically detected from the radar data itself. A final product of 3D attenuation rates and 3D samples count is provided for the research community in this data set. | This attenuation rate data set is obtained by detecting internal reflectors and estimating attenuation within ice using radar data from Investigating the Cryospheric Evolution of the Central Antarctic Plate (ICECAP ) project (https://nsidc.org/data/IR1HI1B/versions/1 and https://nsidc.org/data/IR2HI1B/versions/1) at Law Dome, East Antarctica. The englacial layers are detected with a minimum 60 m spacing between the layers and the attenuation rate is estimated using a mathematical model of constrained optimization. After the estimation of the radar attenuation, the data is post-processed to enhance the quality of the data. In the post-processing step, a 3D grid of 1 km x 1km x 60 m dimension is developed. As the flight lines in the original data provide dense coverage so each grid cell contains many samples (the median is selected among these samples). A second 3D grid is also generated which contains the values that how many samples are contributing to the corresponding grid cell of attenuation rate.