| Title | Impacts of a recent storm surge on an Arctic delta ecosystem examined in the context of the last millennium |
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| Author | Pisaric, M F J; Thienpont, J R; Kokelj, S V; Nesbitt, H; Lantz, T C; Solomon, S; Smol, J P |
| Source | Proceedings of the National Academy of Sciences of the United States of America vol. 108, no. 22, 2011 p. 8960-8965, https://doi.org/10.1073/pnas.1018527108  Open
Access |
| Year | 2011 |
| Alt Series | Natural Resources Canada, Contribution Series 20183066 |
| Publisher | Proceedings of the National Academy of Sciences |
| Document | serial |
| Lang. | English |
| Media | paper; on-line; digital |
| File format | pdf |
| Released | 2011 05 16 |
| Abstract | One of the most ominous predictions related to recent climatic warming is that low-lying coastal environments will be inundated by higher sea levels. The threat is especially acute in polar regions
because reductions in extent and duration of sea ice cover increase the risk of storm surge occurrence. The Mackenzie Delta of northwest Canada is an ecologically significant ecosystem adapted to freshwater flooding during spring breakup. Marine
storm surges during the open-water season, which move saltwater into the delta, can have major impacts on terrestrial and aquatic systems. We examined growth rings of alder shrubs (Alnus viridis subsp. fruticosa) and diatoms preserved in dated lake
sediment cores to show that a recent marine storm surge in 1999 caused widespread ecological changes across a broad extent of the outer Mackenzie Delta. For example, diatom assemblages record a striking shift from freshwater to brackish species
following the inundation event. What is of particular significance is that the magnitude of this recent ecological impact is unmatched over the >1,000-year history of this lake ecosystem. We infer that no biological recovery has occurred in this
lake, while large areas of terrestrial vegetation remain dramatically altered over a decade later, suggesting that these systems may be on a new ecological trajectory. As climate continues to warm and sea ice declines, similar changes will likely be
repeated in other coastal areas of the circumpolar Arctic. Given the magnitude of ecological changes recorded in this study, such impacts may prove to be long lasting or possibly irreversible. |
| GEOSCAN ID | 312910 |
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