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| Titel |
Interrelationships between MODIS/Terra remotely sensed snow cover and the hydrometeorology of the Quesnel River Basin, British Columbia, Canada |
| VerfasserIn |
J. Tong, S. J. Déry, P. L. Jackson |
| Medientyp |
Artikel
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| Sprache |
Englisch
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| ISSN |
1027-5606
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| Digitales Dokument |
URL |
| Erschienen |
In: Hydrology and Earth System Sciences ; 13, no. 8 ; Nr. 13, no. 8 (2009-08-14), S.1439-1452 |
| Datensatznummer |
250011968
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| Publikation (Nr.) |
 copernicus.org/hess-13-1439-2009.pdf |
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| Zusammenfassung |
| 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 1°C 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 (p<0.001) 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 (p<0.01). This clearly demonstrates the strong
links that exist between the SCF depletion and the hydrology of this
sub-boreal, mountainous watershed. |
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