Brief Communication: The reliability of gas extraction techniques for analysing CH4 and N2O compositions in gas trapped in permafrost ice-wedges
Methane (CH 4 ) and nitrous oxide (N 2 O) compositions in ground ice may provide information on their production mechanisms in permafrost. However, existing gas extraction methods has not been well tested. We test conventional wet and dry gas extraction methods using ice-wedges from Alaska and Siber...
| Main Authors: | , , , , , |
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| Format: | Text |
| Language: | English |
| Published: |
2019
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| Subjects: | |
| Online Access: | https://doi.org/10.5194/tc-2019-231 https://www.the-cryosphere-discuss.net/tc-2019-231/ |
| Summary: | Methane (CH 4 ) and nitrous oxide (N 2 O) compositions in ground ice may provide information on their production mechanisms in permafrost. However, existing gas extraction methods has not been well tested. We test conventional wet and dry gas extraction methods using ice-wedges from Alaska and Siberia. We find that both methods extract gas from the easily extractable parts of the ice (e.g., gas bubbles), and yield similar results for CH 4 and N 2 O mixing ratios. We also find insignificant effects of microbial activity during wet extraction. However, both techniques are unable to fully extract gas from the ice, presumably because gas molecules adsorbed onto or enclosed in soil aggregates are not easily extractable. Estimation of gas production in subfreezing environment of permafrost should consider the incomplete gas extraction. |
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