Modelling the L-Band Snow-Covered Surface Emission in a Winter Canadian Prairie Environment

Remote Sensing

卷:10

Chris Derksen¹  Peter Toose¹  Aaron Berg²  Tracy Rowlandson²  Juha Lemmetyinen³  Mike Schwank⁴  Marion Leduc-Leballeur⁵  Ghislain Picard⁶  Alexandre Roy⁷  Alain Royer⁷ 

[1] Climate Research Division, Environment and Climate Change Canada, Toronto, ON M3H 5T4, Canada;

[2] Department of Geography, Environment, and Geomatics University of Guelph, Guelph, ON N1G 2W1, Canada;

[3] Finnish Meteorological Institute, FI-00101 Helsinki, Finland;

[4] Gamma Remote Sensing AG, CH-3073 Gümligen, Switzerland;

[5] Institute of Applied Physics—Ational Research Council, 50019 Sesto Fiorentino, Italy;

[6] Université Grenoble Alpes, CNRS, IGE, F-38000 Grenoble, France;

[7] Université de Sherbrooke, 2500 boul. Université, Sherbrooke, QC J1K 2R1, Canada;

关键词: L-band emission;    snow;    WALOMIS;    Frozen soil;    ground-based radiometer;   

DOI  :  10.3390/rs10091451

来源: DOAJ

【 摘 要 】

Detailed angular ground-based L-band brightness temperature (TB) measurements over snow covered frozen soil in a prairie environment were used to parameterize and evaluate an electromagnetic model, the Wave Approach for LOw-frequency MIcrowave emission in Snow (WALOMIS), for seasonal snow. WALOMIS, initially developed for Antarctic applications, was extended with a soil interface model. A Gaussian noise on snow layer thickness was implemented to account for natural variability and thus improve the TB simulations compared to observations. The model performance was compared with two radiative transfer models, the Dense Media Radiative Transfer-Multi Layer incoherent model (DMRT-ML) and a version of the Microwave Emission Model for Layered Snowpacks (MEMLS) adapted specifically for use at L-band in the original one-layer configuration (LS-MEMLS-1L). Angular radiometer measurements (30°, 40°, 50°, and 60°) were acquired at six snow pits. The root-mean-square error (RMSE) between simulated and measured TB at vertical and horizontal polarizations were similar for the three models, with overall RMSE between 7.2 and 10.5 K. However, WALOMIS and DMRT-ML were able to better reproduce the observed TB at higher incidence angles (50° and 60°) and at horizontal polarization. The similar results obtained between WALOMIS and DMRT-ML suggests that the interference phenomena are weak in the case of shallow seasonal snow despite the presence of visible layers with thicknesses smaller than the wavelength, and the radiative transfer model can thus be used to compute L-band brightness temperature.

【 授权许可】

Unknown