Sensitivity of ice-cemented Antarctic slopes to increases in summer thaw
Summary We employed a Mohr-Coulomb safety factor equation to assess the response of ice-cemented slopes in the stable upland zone of the McMurdo Dry Valleys (MDV) to artificial increases in mean summertime soil surface temperatures (MSSST). Results show that ice-rich, silty tills on slopes 20 ° coul...
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| Format: | Text |
| Language: | English |
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| Online Access: | http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.516.3855 http://pubs.usgs.gov/of/2007/1047/ea/of2007-1047ea039.pdf |
| Summary: | Summary We employed a Mohr-Coulomb safety factor equation to assess the response of ice-cemented slopes in the stable upland zone of the McMurdo Dry Valleys (MDV) to artificial increases in mean summertime soil surface temperatures (MSSST). Results show that ice-rich, silty tills on slopes 20 ° could fail by planar sliding with an in-crease in MSSST of ~5º to 9ºC. This change corresponds to an atmospheric increase of ~5º to 9ºC, which lies just outside the envelope of warming predicted to occur in this region over the next century. If we assume that current soil-moisture conditions can be applied to slope deposits in the distant past, and that these slope deposits have re-mained physically stable for millions of years, then our results suggest that MSSST in the upland zone did not in-crease by more than ~5º to 9ºC since deposition of most deposits, perhaps as much as 10 million years ago. |
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