Snow depth product over Antarctic sea ice from 2002 to 2020 using multisource passive microwave radiometers

• Published in: Earth System Science Data
• Main Authors: X. Shen, C.-Q. Ke, H. Li
• Format: Article in Journal/Newspaper
• Language: English
• Published: Copernicus Publications 2022
• Subjects: Environmental sciences; GE1-350; Geology; QE1-996.5; Antarctic; The Antarctic; Antarc*; Sea ice
• Online Access: https://doi.org/10.5194/essd-14-619-2022; https://doaj.org/article/a6d50d10274e4193bed38f145ed40316

Snow over sea ice controls energy budgets and affects sea ice growth and melting and thus has essential effects on the climate. Passive microwave radiometers can be used for basin-scale snow depth estimation at a daily scale; however, previously published methods applied to the Antarctic clearly underestimated snow depth, limiting their further application. Here, we estimated snow depth using passive microwave radiometers and a newly constructed, robust method by incorporating lower frequencies, which have been available from AMSR-E and AMSR-2 since 2002. A regression analysis using 7 years of Operation IceBridge (OIB) airborne snow depth measurements showed that the gradient ratio (GR) calculated using brightness temperatures in vertically polarized 37 and 7 GHz, i.e. GR(37 <math xmlns="http://www.w3.org/1998/Math/MathML" id="M1" display="inline" overflow="scroll" dspmath="mathml"><mo>/</mo></math> <svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="8pt" height="14pt" class="svg-formula" dspmath="mathimg" md5hash="1b4178c77ca0d4bfee6c9ddd864f3a43"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="essd-14-619-2022-ie00001.svg" width="8pt" height="14pt" src="essd-14-619-2022-ie00001.png"/></svg:svg> 7), was optimal for deriving Antarctic snow depth, with a correlation coefficient of − 0.64. We hence derived new coefficients based on GR(37 <math xmlns="http://www.w3.org/1998/Math/MathML" id="M3" display="inline" overflow="scroll" dspmath="mathml"><mo>/</mo></math> <svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="8pt" height="14pt" class="svg-formula" dspmath="mathimg" md5hash="e653eaf840568ee76bb20ba3bf368ae0"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="essd-14-619-2022-ie00002.svg" width="8pt" height="14pt" src="essd-14-619-2022-ie00002.png"/></svg:svg> 7) to improve the current snow depth estimation from passive microwave radiometers. Comparing the new retrieval with in situ ...