Evaluation of emission from snow-covered ground for passive microwave remote sensing

• Published in: International journal of remote sensing 2012-01, Vol.33 (3), p.872-886
• Main Authors: Jiang, Lingmei, Tjuatja, Saibun, Shi, Jiancheng, Zhang, Lixin, Zhao, Kaiguang
• Format: Article
• Language: English
• Subjects: angle of incidence; microwave radiometers; remote sensing; snow; soil; temperature
• ISSN: 1366-5901; 0143-1161; 1366-5901
• DOI: 10.1080/01431161.2011.577835

This article investigates emission behaviour at frequencies of 18.7, 36.5 and 89 GHz and an incidence angle of 55° over a snow-covered surface at the local scale observation site in Fraser, CO, USA, using both one-layer and two-layer emission models. The models employ the matrix doubling approach to implement the radiative-transfer equation based on dense media theory and the advanced integral equation model. When compared to Ground-Based Passive Microwave Radiometer (GBMR-7) observation on 21 February 2003, both the models could simulate the observed brightness temperature well, but the polarization difference between the observation and the models was smaller for the two-layer emission model than the one-layer model. In addition, we successfully interpreted the emission magnitude and polarization separation of a snow-removed surface by incorporating a Mie scattering transition layer above the soil medium. In this work, we also demonstrated the effect of snow fraction on the brightness temperature difference at 18.7 and 36.5 GHz over a snow-covered surface with the field observation. In conclusion, we demonstrate the snow impact on soil surface with snow depth (SD) and snow fraction variation through modelling and in situ data.