Assessing the effect of sub-grid cell lakes on late winter passive microwave snow water equivalent estimations on the North Slope of Alaska
Thesis (M.S.) University of Alaska Fairbanks, 2007 This research investigates the effect of lakes on late winter Snow Water Equivalent (SWE) and snow depth estimations on the North Slope of Alaska. Time-invariant and temporal sub-grid variability is assessed through the comparison of brightness temp...
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ftunivalaska:oai:scholarworks.alaska.edu:11122/6937 2023-05-15T13:09:08+02:00 Assessing the effect of sub-grid cell lakes on late winter passive microwave snow water equivalent estimations on the North Slope of Alaska Green, Jeffrey Douglas 2007-05 http://hdl.handle.net/11122/6937 en_US eng http://hdl.handle.net/11122/6937 Department of Geology and Geophysics Thesis ms 2007 ftunivalaska 2023-02-23T21:36:44Z Thesis (M.S.) University of Alaska Fairbanks, 2007 This research investigates the effect of lakes on late winter Snow Water Equivalent (SWE) and snow depth estimations on the North Slope of Alaska. Time-invariant and temporal sub-grid variability is assessed through the comparison of brightness temperature evolutions for three grid cells with varying lake fraction. Two new stepwise regression-derived algorithms to estimate SWE and snow depth using brightness temperatures and lake fractions, and two new algorithms to estimate lake fraction using brightness temperatures from SSM/I and AMSR-E are presented. Evaluation of various goodness-of-fit metrics display strengths and weaknesses of each algorithm. The methods employed in this study result in improved estimation with R² values of 0.202 for SWE and 0.292 for snow depth. The two lake fraction estimation algorithms resulted in R² values of 0.509 and 0.738 for SSM/I and AMSR-E, respectively. This study shows that spectral gradient methods utilizing the 19-37 GHz channel difference are not suitable for Alaska North Slope. Lakes were determined to have a strong effect on SWE and snow depth estimation. Inclusion of local lake fraction yielded improvements in performance. 1. Introduction -- 2. Objectives -- 3. Background -- 4. Methods -- 5. Results and discussion -- 6. Conclusions -- References. Thesis Alaska North Slope north slope Alaska University of Alaska: ScholarWorks@UA Fairbanks |
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Open Polar |
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University of Alaska: ScholarWorks@UA |
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ftunivalaska |
language |
English |
description |
Thesis (M.S.) University of Alaska Fairbanks, 2007 This research investigates the effect of lakes on late winter Snow Water Equivalent (SWE) and snow depth estimations on the North Slope of Alaska. Time-invariant and temporal sub-grid variability is assessed through the comparison of brightness temperature evolutions for three grid cells with varying lake fraction. Two new stepwise regression-derived algorithms to estimate SWE and snow depth using brightness temperatures and lake fractions, and two new algorithms to estimate lake fraction using brightness temperatures from SSM/I and AMSR-E are presented. Evaluation of various goodness-of-fit metrics display strengths and weaknesses of each algorithm. The methods employed in this study result in improved estimation with R² values of 0.202 for SWE and 0.292 for snow depth. The two lake fraction estimation algorithms resulted in R² values of 0.509 and 0.738 for SSM/I and AMSR-E, respectively. This study shows that spectral gradient methods utilizing the 19-37 GHz channel difference are not suitable for Alaska North Slope. Lakes were determined to have a strong effect on SWE and snow depth estimation. Inclusion of local lake fraction yielded improvements in performance. 1. Introduction -- 2. Objectives -- 3. Background -- 4. Methods -- 5. Results and discussion -- 6. Conclusions -- References. |
format |
Thesis |
author |
Green, Jeffrey Douglas |
spellingShingle |
Green, Jeffrey Douglas Assessing the effect of sub-grid cell lakes on late winter passive microwave snow water equivalent estimations on the North Slope of Alaska |
author_facet |
Green, Jeffrey Douglas |
author_sort |
Green, Jeffrey Douglas |
title |
Assessing the effect of sub-grid cell lakes on late winter passive microwave snow water equivalent estimations on the North Slope of Alaska |
title_short |
Assessing the effect of sub-grid cell lakes on late winter passive microwave snow water equivalent estimations on the North Slope of Alaska |
title_full |
Assessing the effect of sub-grid cell lakes on late winter passive microwave snow water equivalent estimations on the North Slope of Alaska |
title_fullStr |
Assessing the effect of sub-grid cell lakes on late winter passive microwave snow water equivalent estimations on the North Slope of Alaska |
title_full_unstemmed |
Assessing the effect of sub-grid cell lakes on late winter passive microwave snow water equivalent estimations on the North Slope of Alaska |
title_sort |
assessing the effect of sub-grid cell lakes on late winter passive microwave snow water equivalent estimations on the north slope of alaska |
publishDate |
2007 |
url |
http://hdl.handle.net/11122/6937 |
geographic |
Fairbanks |
geographic_facet |
Fairbanks |
genre |
Alaska North Slope north slope Alaska |
genre_facet |
Alaska North Slope north slope Alaska |
op_relation |
http://hdl.handle.net/11122/6937 Department of Geology and Geophysics |
_version_ |
1766163623508443136 |