Using relative sea-level data to constrain the deglacial and Holocene history of southern Greenland

Abstract

. (2014) 'Using relative sea-level data to constrain the deglacial and Holocene history of southern Greenland.', Quaternary science reviews., 92 . pp. 345-356. Further information on publisher's website:http://dx.doi.org/10.1016/j.quascirev.2013.09.008Publisher's copyright statement: NOTICE: this is the author's version of a work that was accepted for publication in Quaternary Science Reviews. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be re ected in this document. Changes may have been made to this work since it was submitted for publication. A de nitive version was subsequently published in Quaternary Science Reviews, 92, 2014Reviews, 92, , 10.1016Reviews, 92, /j.quascirev.2013 Additional information: Use policyThe full-text may be used and/or reproduced, and given to third parties in any format or medium, without prior permission or charge, for personal research or study, educational, or not-for-pro t purposes provided that:• a full bibliographic reference is made to the original source • a link is made to the metadata record in DRO • the full-text is not changed in any way The full-text must not be sold in any format or medium without the formal permission of the copyright holders.Please consult the full DRO policy for further details. i2

Rapid last-deglacial thinning and retreat of the marine-terminating southwestern Greenland ice sheet

“…Two samples 168 were collected from middle elevations (~250 m asl), and five from low elevations (~65 m 169 asl). The lowest samples from Paamiut were from above, but very close to, the ~50 m asl 170 marine limit (Kelly, 1985;Woodroffe et al, 2014). 171 172…”

Holocene Relative Sea-Level Changes from Near-, Intermediate-, and Far-Field Locations

“…In the near-field location of Greenland, reconstructions from isolation basins provide information on the age of the marine limit of the Greenland Ice Sheet (GrIS) and decimeter-scale changes in RSL since~15 ka [53][54][55][56][57][58][59]. Greenland's RSL history has been dominated by glacio-isostatic uplift from the retreat of the GrIS since the LGM, although spatial variability exists across the region due the variations in local ice load history as well as the influence of the Laurentide deglaciation [60][61][62][63][64].…”

“…On a broader scale, other Greenland sectors show a different pattern in RSL change. Sites in southern Greenland (e.g., Paamiut [59], Nanortalik [61,62], Qaqortoq [62], Tasiusaq [66]) became ice free at~15 ka, after which RSL fell rapidly until it reached its present level at~10 ka and prior to 4 ka fell to a lower lowstand compared to western Greenland of −6 to −8 m. Ammassalik, southeast Greenland [67], shows the characteristic BJ-shaped^form in its RSL history observed in western Greenland, although displays a rapid fall in RSL in the early Holocene more similar to southern Greenland records [64,67], which suggests fast removal of a large volume of ice during initial ice margin retreat in these areas [62,64,67]. Such RSL spatial variability reflects the complex interplay among the GIA response to retreat and advance of the GrIS, glacio-isostatic subsidence from collapse of the Laurentide ice sheet (LIS) proglacial forebulge, and eustatic sea-level rise.…”

Relative Sea-Level Changes and Ice Sheet History in Finderup Land, North Greenland

“…GIA models are fundamental for predicting future scenarios accurately, and are required in order to interpret GPS measurements of uplift caused by present-day ice retreat (Kjeldsen et al, 2015). To ensure accurate predictions, GIA models rely heavily on constraints from field evidence, particularly the timing of ice retreat and the magnitude of isostatic response, which is conveyed through reconstructions of relative sea level (RSL) Sparrenbom et al, 2006a,b;Long et al, 2008Long et al, , 2011Woodroffe et al, 2014;Whitehouse, 2018). Changes in RSL are a product of variations in both global eustatic sea level and local glacial isostasy, the latter being by far the most dominant effect in the near-field area proximal to a large ice sheet (Hay et al, 2014;Dutton et al, 2015;Whitehouse, 2018).…”

“…RSL has traditionally been reconstructed using bivalve shells and driftwood on elevated marine terraces (Washburn and Stuiver, 1962;Funder, 1989;Hjort, 1997). However, recent studies use isolation lakes, which are present-day lakes, distal to the ice-sheet margin, located below the marine limit (Long et al, 1999(Long et al, , 2003(Long et al, , 2008(Long et al, , 2011Long and Roberts, 2002;Sparrenbom et al, 2006aSparrenbom et al, ,b, 2013Woodroffe et al, 2014). As deglaciated areas emerge from below sea level due to glacial isostastic rebound, the depositional environment in the lakes transitions from marine to lacustrine.…”