Reconstruction of the Ice sheet volume and the last deglaciation on Svalbard – constrained by surface Exposure and radiocarbon dating

Participant of Kinnvika and APEX IPY projectsAnne Hormes, UNIS

Arctic Palaeoclimate and its EXtremes (APEX)Endorsed by the ICSU/WMO Joint Committee for IPY as project #39

RISE - project 105

Svendsen et al., 2004

??

What were the dimensions, age and palaeoglaciology of the Arctic ice sheets during glacial maxima?

?

Wally Broecker 1985, etc.

Freshwater forcing of abrupt climate changes?

Size matters!Configuration and size of the last glaciation ice sheet determines the volume of freshwater input at the end of the last glaciation

Marine Geology evidence of Ice streams and trough mouth fans

Source:presentation by Jan Sverre Laberg & Karin Andreassen,University of Tromsø, 2005

No age constrain

Bathymetry west of Prins Karls Forlandet

Core was taken at the continental ridge and a diamict with an infinite radiocarbon age found

Late Glaciation or Older Glaciation?

Till or Debris flow deposits?

Were there ice free areas during LGM?

Landvik et al., Geology, 2003

Cosmogenic nuclide dating using 10Be used on Amsterdamøya and Danskøya indicates that these plateaux were ice free during LGM

Olafur Ingolfsson, AG-321

Brøggerhalvøya exhibits marine terraces with no glacial deposits of LGM

(Forman et al. 2004)

Principle of cosmogenic nuclide dating

lava flowold landscapelandslidemoraineCosmic Radiation

Text

Cosmogenic nuclide dating of erratic boulders east of Riepfjorden July 2007

Text

Cosmogenic nuclide dating of erratic boulders east of Riepfjorden July 2007

Sampling of striated bedrock east of Kinnvika in July 2007

Field sites for mapping and sampling of glacial

polished bedrock, erratic boulders and

trimlines