A New Methodology for Estimating Snow Depth over Arctic Sea Ice
Abstract
Only satellite remote sensing can provide the pan-Arctic view required to fully understand changes to the Earth's sea ice fields. At present, important observational gaps remain which limit both our interpretation of remote-sensing data and our understanding of the Arctic climate system. Snow on sea ice represents both a major source of uncertainty in sea ice concentration and thickness retrievals from satellite data, and a poorly resolved quantity of climactic importance. We hereby introduce the Dual-altimeter Snow Thickness product, (DuST) a new methodology which makes use of coincident satellite altimeter data to derive snow depth at high spatial and temporal resolution. In an initial stage, the difference between the measured freeboards from each altimeter is used to derive a penetration factor for each satellite, i.e. a measurement of the degree to which each radar penetrates the snow (Armitage and Ridout, 2015). Once this has been defined, the difference between the radar penetration factors can be calibrated with a coincident snow depth measurement of high accuracy - in this study we use OIB data - and snow thickness can then be extrapolated over the dual-satellite range. In the initial employment of the DuST methodology here presented, freeboards derived from AltiKa's Ka-band pulse-limited radar altimeter are compared with those from CryoSat-2's SIRAL. Initial validation efforts using data from Arctic ice mass balance buoys suggest promising results from the DuST method.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2016
- Bibcode:
- 2016AGUFM.C13E..08L
- Keywords:
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- 0758 Remote sensing;
- CRYOSPHEREDE: 0799 General or miscellaneous;
- CRYOSPHEREDE: 1240 Satellite geodesy: results;
- GEODESY AND GRAVITYDE: 1241 Satellite geodesy: technical issues;
- GEODESY AND GRAVITY