Snow grain size measurements in Antarctica
Grain size is an important but not well known characteristics of snow at the surface of Antarctica. In the past, grain size has been reported using various methods, the reliability, reproducibility and inter comparability of which is not warranted. In this paper, we present and recommend, depending...
| Main Authors: | , , , , , |
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| Format: | Article in Journal/Newspaper |
| Language: | unknown |
| Published: |
2002
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| Subjects: | |
| Online Access: | https://epic.awi.de/id/eprint/5038/ https://epic.awi.de/id/eprint/5038/1/Gay2002a.pdf https://hdl.handle.net/10013/epic.15606 https://hdl.handle.net/10013/epic.15606.d001 |
| Summary: | Grain size is an important but not well known characteristics of snow at the surface of Antarctica. In the past, grain size has been reported using various methods, the reliability, reproducibility and inter comparability of which is not warranted. In this paper, we present and recommend, depending on available logistical support, 3 techniques of snow grain sampling and /or imaging in the field as well as an ariginal digital image processing method, which we have proved to provide reproducible and intercomparable measures of a snow grain size parameter, the mean convex radius. Results from more than 500 samples and 3000 images of snow grains presented, which yield a still spatially limited, yet unprecendtedly wide picture of near-surface snow grain size distribution from field work in Antarctica. In particular, except at sites affected by a very particular meteorology, surface grains in the interior of the ice sheet are uniformly small (o.1 to 0.2 mm). The climate-related increase of grain size with depth through metamorphism is, as expected, not spatially uniform. Our Antarctic snow grain size database will continue to grow as field investigators bring new samples, images and measures of snow grain size. |
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