Impact of a dynamic snow load on radar altimeter sea ice thickness retrievals
Abstract
Satellite radar altimeter data are now widely used to produce estimates of sea ice thickness across the Arctic Ocean. However, these estimates rely to varying degrees on the use of a snow climatology in the conversion of sea ice freeboard to thickness. The application of a climatological snow load is currently the largest source of error in the ice thickness estimates that we produce at the UK Centre for Polar Observation and Modelling (CPOM) from CryoSat-2 data. To reduce this uncertainty, we have developed a dynamic snow load for application with our sea ice processor that enables us to account for inter-annual and spatial variations in the snow cover. The dynamic snow load model is initialised using precipitation and evaporation data from reanalysis, and developed with a dependence on sea ice concentration, drift, and atmospheric temperature. When applied to CryoSat-2 sea ice observations, the dynamic snow load results in a decrease in ice thickness compared with climatological estimates in regions of seasonal ice cover such as Baffin Bay and the Siberian Shelf Seas. This demonstrates the ability of CryoSat-2 to measure ice thickness over thinner (<0.5 m) ice regimes than previously thought. Here we summarise the development of our dynamic snow load, assess its impact on Arctic-wide sea ice thickness estimates, and evaluate these ice thicknesses using data from NASA'S Operation Icebridge. We will also comment on future developments of the snow load model.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2017
- Bibcode:
- 2017AGUFM.C51A0952T
- Keywords:
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- 0758 Remote sensing;
- CRYOSPHERE;
- 0799 General or miscellaneous;
- CRYOSPHERE;
- 1240 Satellite geodesy: results;
- GEODESY AND GRAVITY;
- 1241 Satellite geodesy: technical issues;
- GEODESY AND GRAVITY