Utforsker Antarktis' isbre-historie
Antarktis har vært islagt i rundt 34 millioner år, isdekket har vokst og krympet med endringer i klimaet. I denne Horisontforelesningen vil professor Sidney R Hemming gi oss en forståelse av isbreene i Antarktis sin historie, noe som er viktig for å forstå hvor sårbart området er for klimaendringer.
Forelesningen er på engelsk.
Antarctica has been located near the south pole for much of the last 600 million years. It was glaciated approximately 300 million years ago, but has otherwise been largely ice free for much of this time. Since about 34 million years ago Antarctica has had major ice sheets.
Where the glaciers bring ice to the shoreline icebergs calve into the ocean. The marine sediment record around Antarctica contains detritus that has been rafted by icebergs, and the variable geology under the ice sheet allows the application of geochemical tracers to determine which sectors are yielding icebergs. Accordingly the study of IRD contributes to our understanding of the ice sheets’ history.
Professor Hemming will present an overview of the correspondence between geochemical tracers and the known geology, and will present some examples of using detritus in marine sediment cores to probe the glacial history of Antarctica’s ice sheets. Understanding the response of Antarctica’s ice sheets through past climate variations informs our ability to predict their future in a warming world.
The lecture starts at 16.15, 14.11.2019, in Egget Auditorium in the Student Centre. Everybody is welcome! Refreshments will be served from 15.45.
Sidney R Hemming
Sidney R Hemming is a Professor in the Department of Earth and Environmental Sciences at Columbia University and is a senior scientist at Lamont-Doherty Earth Observatory. Her expertise is geochronology and isotope geochemistry, and her research history includes a strong focus on using sedimentary provenance studies to tackle paleoclimate questions.