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Holocene relative sea-level changes in the inner Bredefjord area, southern Greenland

Sparrenbom, Charlotte LU ; Bennike, Ole; Fredh, Daniel LU ; Randsalu Wendrup, Linda LU ; Zwartz, Dan; Ljung, Karl LU ; Björck, Svante LU and Lambeck, Kurt (2013) In Quaternary Science Reviews 69. p.107-124
Abstract
In this paper we present new relative sea-level data from southern Greenland, a key area for understanding the Greenland Ice Sheet (GIS) response to climate change. Within fourteen lakes and marine lagoons from the inner part of Bredefjord (Nordre Sermilik) in southern Greenland, isolations revealed by stratigraphic and palaeoecological analyses are dated and relative sea levels reconstructed. Due to coastal emergence caused by the GIS retreat within the area, the relative sea-level fell rapidly in the early Holocene between at least c. 9600 and c. 7300 cal. yrs BP attaining a rate of 2 cm per year between 9600 and 8000 cal. yrs BP. Spatial variability in relative sea-level changes is show for southern Greenland from a comparison with the... (More)
In this paper we present new relative sea-level data from southern Greenland, a key area for understanding the Greenland Ice Sheet (GIS) response to climate change. Within fourteen lakes and marine lagoons from the inner part of Bredefjord (Nordre Sermilik) in southern Greenland, isolations revealed by stratigraphic and palaeoecological analyses are dated and relative sea levels reconstructed. Due to coastal emergence caused by the GIS retreat within the area, the relative sea-level fell rapidly in the early Holocene between at least c. 9600 and c. 7300 cal. yrs BP attaining a rate of 2 cm per year between 9600 and 8000 cal. yrs BP. Spatial variability in relative sea-level changes is show for southern Greenland from a comparison with the Nanortalik and the Qagortoq areas. The regression occurred about 2000 years later in the inner Bredefjord area, compared to the Nanortalik area, and about 1000 years later compared to the Qaqortoq area. This is a consequence of earlier deglaciation in areas located at the outer coast. Between c. 8000 cal. yrs BP and the present day, relative sea level was lower than today. The lowest relative sea level in the Inner Bredefjord area of between -5.4 and -15 m a.h.a.t. (above highest astronomical tide) was reached between 7000 and 1000 cal. yrs BP. The neoglacial readvance together with the collapse of the Laurentide peripheral bulge is probably responsible for the transgression in the Inner Bredefjord area, as has been indicated from the nearby sites Qagortoq and Nanortalik. Our relative sea-level reconstructions showing spatial variability within southern Greenland have implications for Glacial Isostatic Adjustment (GIA) modelling and the understanding of the GIS ice sheet dynamics. The early Holocene regression is consistent with the recession of the southern sector of the GIS from the shelf edge at c. 22 000 cal. yrs BP, reaching inland of the present day outer coast by c. 12 000 cal. yrs BP, and its present margin by c. 10 500 cal. yrs BP. (c) 2013 Elsevier Ltd. All rights reserved. (Less)
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author
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
Sea-level change, Greenland Ice Sheet, Isolation basin, Isostatic, rebound, Transgression
in
Quaternary Science Reviews
volume
69
pages
107 - 124
publisher
Elsevier
external identifiers
  • wos:000320484800009
  • scopus:84876324678
ISSN
0277-3791
DOI
10.1016/j.quascirev.2013.02.020
project
BECC
MERGE
language
English
LU publication?
yes
id
deef324d-19e5-4fcf-9d19-c7a57b1e4c6a (old id 3983239)
date added to LUP
2013-09-05 15:53:19
date last changed
2018-10-03 10:35:56
@article{deef324d-19e5-4fcf-9d19-c7a57b1e4c6a,
  abstract     = {In this paper we present new relative sea-level data from southern Greenland, a key area for understanding the Greenland Ice Sheet (GIS) response to climate change. Within fourteen lakes and marine lagoons from the inner part of Bredefjord (Nordre Sermilik) in southern Greenland, isolations revealed by stratigraphic and palaeoecological analyses are dated and relative sea levels reconstructed. Due to coastal emergence caused by the GIS retreat within the area, the relative sea-level fell rapidly in the early Holocene between at least c. 9600 and c. 7300 cal. yrs BP attaining a rate of 2 cm per year between 9600 and 8000 cal. yrs BP. Spatial variability in relative sea-level changes is show for southern Greenland from a comparison with the Nanortalik and the Qagortoq areas. The regression occurred about 2000 years later in the inner Bredefjord area, compared to the Nanortalik area, and about 1000 years later compared to the Qaqortoq area. This is a consequence of earlier deglaciation in areas located at the outer coast. Between c. 8000 cal. yrs BP and the present day, relative sea level was lower than today. The lowest relative sea level in the Inner Bredefjord area of between -5.4 and -15 m a.h.a.t. (above highest astronomical tide) was reached between 7000 and 1000 cal. yrs BP. The neoglacial readvance together with the collapse of the Laurentide peripheral bulge is probably responsible for the transgression in the Inner Bredefjord area, as has been indicated from the nearby sites Qagortoq and Nanortalik. Our relative sea-level reconstructions showing spatial variability within southern Greenland have implications for Glacial Isostatic Adjustment (GIA) modelling and the understanding of the GIS ice sheet dynamics. The early Holocene regression is consistent with the recession of the southern sector of the GIS from the shelf edge at c. 22 000 cal. yrs BP, reaching inland of the present day outer coast by c. 12 000 cal. yrs BP, and its present margin by c. 10 500 cal. yrs BP. (c) 2013 Elsevier Ltd. All rights reserved.},
  author       = {Sparrenbom, Charlotte and Bennike, Ole and Fredh, Daniel and Randsalu Wendrup, Linda and Zwartz, Dan and Ljung, Karl and Björck, Svante and Lambeck, Kurt},
  issn         = {0277-3791},
  keyword      = {Sea-level change,Greenland Ice Sheet,Isolation basin,Isostatic,rebound,Transgression},
  language     = {eng},
  pages        = {107--124},
  publisher    = {Elsevier},
  series       = {Quaternary Science Reviews},
  title        = {Holocene relative sea-level changes in the inner Bredefjord area, southern Greenland},
  url          = {http://dx.doi.org/10.1016/j.quascirev.2013.02.020},
  volume       = {69},
  year         = {2013},
}