Holocene ice marginal fluctuations of the Qassimiut lobe in South Greenland

TY - JOUR

T1 - Holocene ice marginal fluctuations of the Qassimiut lobe in South Greenland

AU - Larsen, Nicolaj K.

AU - Find, Jesper

AU - Kristensen, Anders

AU - Bjørk, Anders Anker

AU - Kjeldsen, Kristian Kjellerup

AU - Odgaard, Bent V.

AU - Olsen, Jesper

AU - Kjær, Kurt H.

PY - 2016/3/4

Y1 - 2016/3/4

N2 - Knowledge about the Holocene evolution of the Greenland ice sheet (GrIS) is important to put the recent observations of ice loss into a longer-term perspective. In this study, we use six new threshold lake records supplemented with two existing lake records to reconstruct the Holocene ice marginal fluctuations of the Qassimiut lobe (QL) - one of the most dynamic parts of the GrIS in South Greenland. Times when the ice margin was close to present extent are characterized by clastic input from the glacier meltwater, whereas periods when the ice margin was behind its present day extent comprise organic-rich sediments. We find that the overall pattern suggests that the central part of the ice lobe in low-lying areas experienced the most prolonged ice retreat from ~9-0.4 cal. ka BP, whereas the more distal parts of the ice lobe at higher elevation re-advanced and remained close to the present extent during the Neoglacial between ~4.4 and 1.8 cal. ka BP. These results demonstrate that the QL was primarily driven by Holocene climate changes, but also emphasises the role of local topography on the ice marginal fluctuations.

AB - Knowledge about the Holocene evolution of the Greenland ice sheet (GrIS) is important to put the recent observations of ice loss into a longer-term perspective. In this study, we use six new threshold lake records supplemented with two existing lake records to reconstruct the Holocene ice marginal fluctuations of the Qassimiut lobe (QL) - one of the most dynamic parts of the GrIS in South Greenland. Times when the ice margin was close to present extent are characterized by clastic input from the glacier meltwater, whereas periods when the ice margin was behind its present day extent comprise organic-rich sediments. We find that the overall pattern suggests that the central part of the ice lobe in low-lying areas experienced the most prolonged ice retreat from ~9-0.4 cal. ka BP, whereas the more distal parts of the ice lobe at higher elevation re-advanced and remained close to the present extent during the Neoglacial between ~4.4 and 1.8 cal. ka BP. These results demonstrate that the QL was primarily driven by Holocene climate changes, but also emphasises the role of local topography on the ice marginal fluctuations.

U2 - 10.1038/srep22362

DO - 10.1038/srep22362

M3 - Journal article

C2 - 26940998

SN - 2045-2322

VL - 6

JO - Scientific Reports

JF - Scientific Reports

M1 - 22362

ER -