1. Surface Melting Drives Fluctuations in Airborne Radar Penetration in West Central Greenland
- Author
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Otosaka, Ines, Shepherd, A., Casal, Tania, coccia, alex, Davidson, Malcolm, Di Bella, Alessandro, Fettweis, X.R., Forsberg, René, Helm, Veit, Hogg, Anna E., Hvidegaard, Sine, Lemos, A., Macedo, Karlus, Kuipers Munneke, P., Parrinello, Tommaso, Simonsen, Sebastian B., Skourup, Henriette, Sørensen, Louise Sandberg, Sub Dynamics Meteorology, Marine and Atmospheric Research, Sub Dynamics Meteorology, and Marine and Atmospheric Research
- Subjects
010504 meteorology & atmospheric sciences ,Greenland ,Greenland ice sheet ,firn ,010502 geochemistry & geophysics ,01 natural sciences ,law.invention ,law ,altimetry ,Cryosphere ,Altimeter ,Radar ,Geomorphology ,0105 earth and related environmental sciences ,geography ,geography.geographical_feature_category ,Scattering ,Firn ,Penetration (firestop) ,ice sheet ,Geophysics ,13. Climate action ,General Earth and Planetary Sciences ,Ice sheet ,Geology ,radar - Abstract
Greenland Ice Sheet surface melting has increased since the 1990s, affecting the rheology and scattering properties of the near‐surface firn. We combine firn cores and modelled firn densities with seven years of CryoVEx airborne Ku‐band (13.5 GHz) radar profiles to quantify the impact of melting on microwave radar penetration in West‐Central Greenland. Although annual layers are present in the Ku‐band radar profiles to depths up to 15 m below the ice sheet surface, fluctuations in summer melting strongly affect the degree of radar penetration. The extreme melting in 2012, for example, caused an abrupt 6.2 ± 2.4 m decrease in Ku‐band radar penetration. Nevertheless, retracking the radar echoes mitigates this effect, producing surface heights that agree to within 13.9 cm of coincident airborne laser measurements. We also examine two years of Ka‐band (34.5 GHz) airborne radar data and show that the degree of penetration is half that of coincident Ku‐band.
- Published
- 2020