News & Events

Grad student talk - A 1700 year record of ocean influence on Jakobshavn Isbræ calving activity based

Thursday, September 08, 2016, 12:30PM - 1:30PM

Speaker

David Wangner

Location:

SEEC room 225

Full title

A 1700 year record of ocean influence on Jakobshavn Isbrae calving activity based on marine sediment cores from Disko Bay

Abstract

The Greenland ice sheet experienced a significant mass loss in recent years. This is also shown in the retreat of most marine terminating glaciers, which lost mass by increased calving rates and meltwater discharge. Instrumental observations of local air temperature only cover a limited time span of up to 140 years and observations of glacier changes are mainly limited to the past 40 years. In order to reconstruct glacier behavior in response to climate change further in the past and to put these changes into the right historical context three sediment cores in Disko Bay near the outlet of Jakobshavn fjord were collected. The deposited sediments at this site reflect the oceanographic and environmental changes as well as the discharge of one of the most productive marine terminating glaciers in Greenland, the Jakobshavn Isbræ.

This talk will be about results of radiocarbon dating, high-resolution grain size analyses, X-Ray, XRF and magnetic susceptibility measurements. Furthermore, it will include preliminary results of foraminifera assemblages.