Title Interrelationships between MODIS/Terra remotely sensed snow cover and the hydrometeorology of the Quesnel River Basin, British Columbia, Canada
Author Tong, J.; Dry, S.J.; Jackson, P.L.
Author Affil Tong, J., University of Northern British Columbia, Natural Resources and Environmental Studies, Prince George, BC, Canada
Source Hydrology and Earth System Sciences (HESS), 13(8), p.1439-1452, . Publisher: Copernicus GmbH on behalf of the European Geosciences Union, Katlenburg-Lindau, Germany. ISSN: 1027-5606
Publication Date 2009
Notes In English. Published in Hydrology and Earth System Science Discussion: 5 May 2009, http://www.hydrol-earth-syst-sci- discuss.net/6/3687/2009/hessd-6-3687-20 09.html; abstract: doi:10.5194/hess-13-1439- 2009; accessed in July, 2010. 35 refs. GeoRef Acc. No: 309772
Index Terms ablation; Alpine landscapes; alpine tundra; climatic change; clouds (meteorology); filters; forest tundra; glaciers; glacial hydrology; glacier ablation; hydrodynamics; hydrologic cycle; hydrology; meteorology; remote sensing; runoff; snow; statistical analysis; river flow; tundra; watersheds; Canada--British Columbia--Fraser River; Canada--British Columbia--Quesnel Lake; alpine environment; boreal environment; British Columbia; Canada; catchment hydrodynamics; climate change; clouds; correlation coefficient; forests; Fraser River; MOD10A2; MODIS; mountains; Quesnel Lake; Quesnel River Basin; spatial frequency filters; streamflow; Terra; terrestrial environment; Western Canada
Abstract A spatial filter (SF) method is adopted to reduce the cloud coverage from the Moderate Resolution Imaging Spectroradiometer (MODIS) 8-day snow products (MOD10A2) between 2000- 2007 in the Quesnel River Basin (QRB) of British Columbia, Canada. A threshold of k=2 cm of snow depth measurements at four in-situ observation stations in the QRB are used to evaluate the accuracy of MODIS snow products MOD10A1, MOD10A2, and SF. Using the MOD10A2 and the SF, the relationships between snow ablation, snow cover extent (SCE), snow cover fraction (SCF), streamflow and climate variability are assessed. Based on our results we are able to draw several interesting conclusions. Firstly, the SF method reduces the average cloud coverage in the QRB from 15% for MOD10A2 to 9%. Secondly, the SF increases the overall accuracy (OA) based on the threshold k=2 cm by about 2% compared to MOD10A2 and by about 10% compared to MOD10A1 at higher elevations. The OA for the four in-situ stations decreases with elevation with 93.1%, 87.9%, 84.0%, and 76.5% at 777 m, 1265 m, 1460 m, and 1670 m, respectively. Thirdly, an aggregated 1C rise in average air temperature during spring leads to a 10-day advance in reaching 50% SCF (SCF50%) in the QRB. The correlation coefficient between normalized SCE of the SF and normalized streamflow is -0.84 (p0.001) for snow ablation seasons. There is a 32-day time lag for snow ablation to impact the streamflow the strongest at the basin outlet. The linear correlation coefficient between SCF50% and 50% normalized accumulated runoff (R50%) attains 0.82 (p0.01). This clearly demonstrates the strong links that exist between the SCF depletion and the hydrology of this sub-boreal, mountainous watershed.
URL http://www.hydrol-earth-syst-sci.net/13/1439/2009/hess-13-1439-2009.pdf
Publication Type journal article
Record ID 65006340