Blowing snow in East Antarctica: comparison of ground-based and space-borne retrievals

• Main Authors: Gossart, Alexandra, Palm, Stephen P., Souverijns, Niels, Lenaerts, Jan T. M., Gorodetskaya, Irina V., Lhermitte, Stef, Lipzig, Nicole P. M.
• Format: Text
• Language: English
• Published: 2019
• Subjects: East Antarctica; Neumayer; Antarc*; Antarctica
• Online Access: https://doi.org/10.5194/tc-2019-25; https://tc.copernicus.org/preprints/tc-2019-25/

Continuous measurements of blowing snow are scarce, both in time and space. Satellites now provide the opportunity to derive blowing snow occurrences, transport and sublimation rates over Antarctica. However, little ground truth is available to validate these retrievals. The recent application of ceilometers for detection of blowing snow frequencies provides an opportunity to validate the satellite retrievals of blowing snow frequencies at the Princess Elisabeth and Neumayer stations, East Antarctica for the 2011–2016 time period. A routine to detect blowing snow occurrence from remote sensing ceilometers has been developed at those locations. Thanks to their ground-based location, ceilometers are able to detect blowing snow events in the presence of clouds and precipitation, which can be missed by the satellite, since optically thick clouds impede the penetration of the signal. This is important, since ≈ 90 % of blowing snow happens under cloudy conditions at Neumayer and Princess Elisabeth station and represent 30 % of all cloudy conditions at both stations. Although both detection methods have their limitations, 10 % (4 %) of the measurements at Princess Elisabeth (and Neumayer) are identified as blowing snow by the satellite but not by the ceilometer, likely due to differences in sensors, limitation of the surface identification by the satellite, or the spatial inhomogeneity of the blowing snow event. While the satellite blowing snow retrieval is a useful product, further investigation is needed to reduce the uncertainties on blowing snow frequencies associated with clouds.