Polar firn properties in Greenland and Antarctica and related effects on microwave brightness temperatures

Abstract GHz brightness temperatures and snow radar echo peaks in measurements performed in Greenland in 2017. Based on these insights, a new analytical partially coherent model is implemented to explain the microwave brightness temperatures using the three-scale description of the firn. Short- and long-scale firn processes are modeled as a 3D continuous random medium with finite vertical and horizontal correlation lengths as opposed to past 1D randomly layered medium descriptions. Refrozen layers are described as deterministic sheets with planar interfaces, with the number of refrozen-layer interfaces determined by radar observations. Firn density and correlation length parameters used in forward modeling to match measured 0.5–2 GHz brightness temperatures in Greenland show consistency with similar parameters in CFM predictions. Model predictions also are in good agreement with multi-angle 1.4 GHz vertically and horizontally polarized brightness temperature measured by the Soil Moisture and Ocean Salinity (SMOS) satellite at Dome C, Antarctica. This work shows that co-located active and passive microwave measurements can be used to infer polar firn properties that can be compared with predictions of the CFM. In particular, 0.5–2 GHz brightness temperature measurements are shown to be sensitive to long-scale firn density fluctuations with density standard deviations in the range of 0.01–0.06 g cm - 3 and vertical correlation lengths of 6–20 cm.

Object Details

• Location: Deutsche Nationalbibliothek Frankfurt am Main
• Extent: Online-Ressource
• Language: Englisch

References and Relationships

• Bibliographic citation: Polar firn properties in Greenland and Antarctica and related effects on microwave brightness temperatures ; volume:17 ; number:7 ; year:2023 ; pages:2793-2809 ; extent:17 ; The Cryosphere ; 17, Heft 7 (2023), 2793-2809 (gesamt 17)

Contributors, Places and Time

• Creator: Xu, Haokui ; Medley, Brooke ; Tsang, Leung ; Johnson, Joel T. ; Jezek, Kenneth C. ; Brogioni, Macro ; Kaleschke, Lars

Further information

• DOI: 10.5194/tc-17-2793-2023
• URN: urn:nbn:de:101:1-2023072004385602946996
• Rights: Open Access; Der Zugriff auf das Objekt ist unbeschränkt möglich.
• Last update: 14.08.2025, 10:59 AM CEST