Salt-marsh reconstructions of relative sea-level change in the North Atlantic during the last 2000 years

Barlow, N.L.M.; Long, A.J.; Saher, M.H.; Gehrels, W.R.; Garnett, M.H.; Scaife, R.G.

Abstract

Sea-level changes record changes in the mass balance of ice sheets and mountain glaciers, as well as dynamic ocean-atmosphere processes. Unravelling the contribution of each of these mechanisms on late Holocene timescales ideally requires observations from a number of sites on several coasts within one or more oceans. We present the first 2000 year-long continuous salt marsh-based reconstructions of relative sea-level (RSL) change from the eastern North Atlantic and uniquely from a slowly uplifting coastline. We develop three RSL histories from two sites in north west Scotland to test for regional changes in sea-level tendency (a positive tendency indicating an increase in the proximity of marine conditions and a negative tendency the reverse), whilst at the same time highlighting methodological issues, including the problems of dataset noise when applying transfer functions to fossil salt-marsh sequences. The records show that RSL has been stable (±0.4 m) during the last two millennia, and that the regional sea-level tendency has been negative throughout most of the record lengths. A recent switch in the biostratigraphy of all three records, indicating a regional positive tendency, means we cannot reject the hypothesis of a 20th century sea-level acceleration occurring in north west Scotland that must have exceeded the rate of background RSL fall (-0.4 mm yr-1), but this signal appears muted and later than recorded from the western North Atlantic.

Citation

Barlow, N., Long, A., Saher, M., Gehrels, W., Garnett, M., & Scaife, R. (2014). Salt-marsh reconstructions of relative sea-level change in the North Atlantic during the last 2000 years. Quaternary Science Reviews, 99, 1-16. https://doi.org/10.1016/j.quascirev.2014.06.008

• Journal Article Type: Article
• Publication Date: Sep 1, 2014
• Deposit Date: Jun 10, 2014
• Publicly Available Date: Jul 8, 2014
• Journal: Quaternary Science Reviews
• Print ISSN: 0277-3791
• Electronic ISSN: 1873-457X
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 99
• Pages: 1-16
• DOI: https://doi.org/10.1016/j.quascirev.2014.06.008
• Keywords: North Atlantic, Sea level, Transfer function, Diatoms, Foraminifera, Salt marsh, Climate.
• Public URL: https://durham-repository.worktribe.com/output/1425656