Permafrost in circum-polar regions has been recently undergoing thawing, with severe environmental consequences, including the release of greenhouse gases and amplification of global warming. Although highly important, direct methods of tracking thawing hardly exist. In a research study conducted at Adventdalen, Svalbard, we identified a permafrost radioisotope fingerprint, and show that it can be used to track thawing. Ratios of long- to the shorter-lived radium isotopes are higher in ground ice than in active layer water, which we attribute to the permafrost closed system and possibly to the long residence time of ground ice in the permafrost. Also, daughter–parent 224Ra/228Ra ratios are lower in permafrost than in the active layer. These fingerprints were also identified in a local stream, confirming the applicability of this tool to tracing thawed permafrost in periglacial watersheds. A combination of radium isotope ratios and 3H allowed the identification of recent intra-permafrost segregation processes. The permafrost radium fingerprint should be applicable to other permafrost areas, which could assist in regional quantification of the extent of permafrost thawing and carbon emissions to the atmosphere.
|Number of pages||9|
|Journal||Permafrost and Periglacial Processes|
|State||Published - 1 Apr 2019|
Bibliographical noteFunding Information:
Israel Science Foundation, Grant/Award Number: Bikura grant 1487/14; Svalbard Science Forum, Grant/Award Number: Arctic Field Grant 2017
We wish to express our gratitude to Dany Roehnert, Yehuda Shalem, Graham Gilbert, Gunnar Mallon, Eleanor Jones and Ebbe Norskov Bak, who assisted with the hard field and lab work, as well as to all UNIS staff, who helped in different ways to accomplish this study. This research was funded by Israel Science Foundation Bikura grant 1487/14, and partly by an Arctic Field Grant of the Svalbard Science Forum allocated to Dotan Rotem in 2017.
© 2019 John Wiley & Sons, Ltd.
- active layer
- permafrost thawing
- radium isotopes