Southwest-facing slopes control the formation of debris-covered glaciers in the Bhutan Himalaya
To understand the formation conditions of debris-covered glaciers, we examined the dimension and shape of debris-covered areas and potential debris-supply (PDS) slopes of 213 glaciers in the Bhutan Himalaya. This was undertaken using satellite images with 2.5 m spatial resolution for manual delineat...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
| Published: |
Copernicus Publications
2013-08-01
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| Series: | The Cryosphere |
| Online Access: | http://www.the-cryosphere.net/7/1303/2013/tc-7-1303-2013.pdf |
| _version_ | 1819169014038921216 |
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| author | H. Nagai K. Fujita T. Nuimura A. Sakai |
| author_facet | H. Nagai K. Fujita T. Nuimura A. Sakai |
| author_sort | H. Nagai |
| collection | DOAJ |
| description | To understand the formation conditions of debris-covered glaciers, we examined the dimension and shape of debris-covered areas and potential debris-supply (PDS) slopes of 213 glaciers in the Bhutan Himalaya. This was undertaken using satellite images with 2.5 m spatial resolution for manual delineation of debris-covered areas and PDS slopes. The most significant correlation exists between surface area of southwest-facing PDS slopes and debris-covered area. This result suggests that the southwest-facing PDS slopes supply the largest quantity of debris mantle. The shape of debris-covered areas is also an important variable, quantitatively defined using a geometric index. Elongate or stripe-like debris-covered areas on north-flowing glaciers are common throughout the Bhutan Himalaya. In contrast, south-flowing glaciers have large ablation zones, entirely covered by debris. Our findings suggest that this difference is caused by effective diurnal freeze–thaw cycles rather than seasonal freeze–thaw cycles, permafrost degradation, or snow avalanches. In terms of geographic setting, local topography also contributes to glacier debris supply and the proportion of debris cover on the studied glaciers is suppressed by the arid Tibetan climate, whereas the north-to-south asymmetric topography of the Bhutan Himalaya has less influence on the proportion of debris cover. |
| first_indexed | 2024-12-22T19:12:45Z |
| format | Article |
| id | doaj.art-6073943365f84b40864b40a566cec8a8 |
| institution | Directory Open Access Journal |
| issn | 1994-0416 1994-0424 |
| language | English |
| last_indexed | 2024-12-22T19:12:45Z |
| publishDate | 2013-08-01 |
| publisher | Copernicus Publications |
| record_format | Article |
| series | The Cryosphere |
| spelling | doaj.art-6073943365f84b40864b40a566cec8a82022-12-21T18:15:36ZengCopernicus PublicationsThe Cryosphere1994-04161994-04242013-08-01741303131410.5194/tc-7-1303-2013Southwest-facing slopes control the formation of debris-covered glaciers in the Bhutan HimalayaH. NagaiK. FujitaT. NuimuraA. SakaiTo understand the formation conditions of debris-covered glaciers, we examined the dimension and shape of debris-covered areas and potential debris-supply (PDS) slopes of 213 glaciers in the Bhutan Himalaya. This was undertaken using satellite images with 2.5 m spatial resolution for manual delineation of debris-covered areas and PDS slopes. The most significant correlation exists between surface area of southwest-facing PDS slopes and debris-covered area. This result suggests that the southwest-facing PDS slopes supply the largest quantity of debris mantle. The shape of debris-covered areas is also an important variable, quantitatively defined using a geometric index. Elongate or stripe-like debris-covered areas on north-flowing glaciers are common throughout the Bhutan Himalaya. In contrast, south-flowing glaciers have large ablation zones, entirely covered by debris. Our findings suggest that this difference is caused by effective diurnal freeze–thaw cycles rather than seasonal freeze–thaw cycles, permafrost degradation, or snow avalanches. In terms of geographic setting, local topography also contributes to glacier debris supply and the proportion of debris cover on the studied glaciers is suppressed by the arid Tibetan climate, whereas the north-to-south asymmetric topography of the Bhutan Himalaya has less influence on the proportion of debris cover.http://www.the-cryosphere.net/7/1303/2013/tc-7-1303-2013.pdf |
| spellingShingle | H. Nagai K. Fujita T. Nuimura A. Sakai Southwest-facing slopes control the formation of debris-covered glaciers in the Bhutan Himalaya The Cryosphere |
| title | Southwest-facing slopes control the formation of debris-covered glaciers in the Bhutan Himalaya |
| title_full | Southwest-facing slopes control the formation of debris-covered glaciers in the Bhutan Himalaya |
| title_fullStr | Southwest-facing slopes control the formation of debris-covered glaciers in the Bhutan Himalaya |
| title_full_unstemmed | Southwest-facing slopes control the formation of debris-covered glaciers in the Bhutan Himalaya |
| title_short | Southwest-facing slopes control the formation of debris-covered glaciers in the Bhutan Himalaya |
| title_sort | southwest facing slopes control the formation of debris covered glaciers in the bhutan himalaya |
| url | http://www.the-cryosphere.net/7/1303/2013/tc-7-1303-2013.pdf |
| work_keys_str_mv | AT hnagai southwestfacingslopescontroltheformationofdebriscoveredglaciersinthebhutanhimalaya AT kfujita southwestfacingslopescontroltheformationofdebriscoveredglaciersinthebhutanhimalaya AT tnuimura southwestfacingslopescontroltheformationofdebriscoveredglaciersinthebhutanhimalaya AT asakai southwestfacingslopescontroltheformationofdebriscoveredglaciersinthebhutanhimalaya |