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This archive contains firn temperature data collected at two sites in the western Greenland Ice Sheet percolation zone. The sites, T3 and Crawford Point (CP), are located along the Expéditions Glaciologiques Internationales au Groenland (EGIG) line. The data are time series of firn temperature measured in boreholes drilled to 100 m depth. The boreholes were drilled by hot water methods. The CP measurements span the period June to August, 2019. This borehole was drilled in 2018, so the temperature profile had fully recovered from the drilling thermal disturbance by the start of the time series. The T3 data span the period June 2019 to September 2021. This borehole was drilled in June 2019, so the time series of measurements includes the thermal recovery from drilling (several months) and two subsequent years. The dataset was collected as part of projects funded by the U.S. National Science Foundation. These measurements are associated with additional datasets collected as part of a NSF Arctic Observing Network project, and include measurements at multiple sites on the EGIG line of firn temperature and firn density/ice content.
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Hot water drilling in the firn layer of Greenland's percolation zone
Abstract The intermixed thermal and structural framework of cold firn, water-saturated firn and ice layers in Greenland's percolation zone can be challenging to penetrate with core drills. Here, we present our experiences using a hot water drill for research on the firn layer of the percolation zone. We built and deployed a lightweight and easily transportable system for drilling a transect of ~15 cm diameter boreholes through the full firn column thickness, to depths exceeding 100 m. An instrumented drill stem provides a scientific measurement of the firn properties while drilling. The system was successful at gaining rapid access to the firn column with mixed wet and cold conditions, was easily transported to the site and across the glacier surface, and required a small field crew to operate. The boreholes are well suited for in situ investigations of firn processes in Greenland percolation zone.
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- PAR ID:
- 10222468
- Date Published:
- Journal Name:
- Annals of Glaciology
- ISSN:
- 1727-5644
- Page Range / eLocation ID:
- 1 to 4
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1017/aog.2020.75
