Our first talk for the Fall 2012 semester will be a great one, from Prof. Stephen Pekar on ancient changes in Antarctic Ice Volumes.  Prof. Pekar is a researcher at the Lamont-Doherty Earth Observatory, as well as an instructor at CUNY Queens.

The talk will begin at 5:30 on Thursday, September 6th, in the Graduate Center, in the 4th Floor Science Center (Room 4102).

 

Dr. Pekar is heavily involved with the Integrated Ocean Drilling Program and the Antarctic Drilling Program (ANDRILL) and has served on expeditions to the Antarctic, where ocean floor sediments, including important proxies for past climate, have been retreived. Prof. Pekar studies the make-up and stratigraphy of these materials in order to better understand changes in the all-important Ice Volume of the Antarctic Ice Sheets. At points in Earth’s past, the Antarctic was ice-free, but of course today the continent is layered in a thick sheet of ice. The stability of this ice sheet is a terribly important question when it comes to predicting future changes in sea level. In the Mesozoic, when both poles were ice-free, the middle of the United States was submerged under the great “Western Interior” Sea, in fact North America was broken up into three island-continents because of this.  Today much of that water has been pulled out of the oceans and is held, frozen, in the Ice Sheets.

The onset of Ice Sheets in the Antarctic is also one of the areas in paleo-climate studies that is somewhat controversial, some workers believe that once the Ice Sheets were established they remained unchanged, and Antarctica was essentially “dry”  (despite the ice cover, there was little free flowing water). Other workers believe that the Ice Sheets were much more dynamic, with periods in which they grew and shrank, and times when there was free water on the continent. Dr. Pekar has been heavily involved in this scientific debate, and his talk will likely touch on this and other climate-science issues.

Please follow the link below for a promotional flyer for Dr. Pekar’s talk:

Past Climate and Ice-Volume Changes in Antarctica: Looking Back to Our Future