DocumentCode :
2091056
Title :
Retrieval of snow water equivalent over boreal forest in Canada from passive microwave measurements using the HUT snow emission model
Author :
Roy, V. ; Goïta, K. ; Royer, A. ; Walker, A.E. ; Goodison, B.E.
Author_Institution :
CARTEL, Sherbrooke Univ., Que., Canada
Volume :
1
fYear :
2002
fDate :
2002
Firstpage :
220
Abstract :
The objective of this research is to validate the Helsinki University of Technology (HUT) snow emission model and evaluate it´s efficiency for snow water equivalent (SWE) estimation in a Canadian boreal forest environment. The model validation over the BOREAS study area shows a correlation (R2≥0.4) between the errors in the simulated brightness temperatures and the snow grain size, which controls the snow cover extinction behavior in the HUT model. Therefore, we propose a different empirical relationship for the extinction coefficient of the snow cover for the environment considered. Better predictions of brightness temperatures at 18 and 37 GHz in both polarizations were obtained using this relation. The accuracy of SWE estimated by inverse modeling based on minimization techniques was also improved, with a mean retrieval error on SWE of less than 15 mm and negligible bias. In comparison, conventional empirical algorithms, based on brightness temperature gradients, tend to underestimate SWE in boreal conditions with a mean retrieval error in the order of 20 to 30 mm.
Keywords :
hydrological techniques; radiometry; remote sensing; snow; 18 GHz; 37 GHz; AD 1994; BOREAS; Canada; EHF; HUT; Helsinki University of Technology; Manitoba; SHF; Saskatchewan; boreal forest; brightness temperature; hydrology; measurement technique; microwave polarimetry; microwave radiometry; passive microwave method; polarization; remote sensing; snow cover; snow emission model; snow grain size; snow water equivalent; snowcover; validation; vegetation; Brightness temperature; Error correction; Extinction coefficients; Grain size; Inverse problems; Microwave measurements; Polarization; Size control; Snow; Temperature control;
fLanguage :
English
Publisher :
ieee
Conference_Titel :
Geoscience and Remote Sensing Symposium, 2002. IGARSS '02. 2002 IEEE International
Print_ISBN :
0-7803-7536-X
Type :
conf
DOI :
10.1109/IGARSS.2002.1024993
Filename :
1024993
Link To Document :
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