The Past as Prologue - Michael Mann

Penn State University Climatologist Michael Mann. After: Physicist and climatologist Michael Mann. Photograph: http://www.guardian.co.uk/environment/2012/mar/05/climate-change-hockey-stick-michael-mann

Dr. Michael Mann is going to give a talk at the CUNY Graduate Center, Thursday May 9th. The talk will be on the 4th Floor in the Science Center, room 4102. This talk will start at 530pm. As usual, after the talk we'll have an informal reception.

Michael Mann is a well known climate researcher who's 1998 publication "Global-scale temperature patterns and climate forcing over the past six centuries" (pdf) is the source of the famous (well, famous as statistical graphs go) "Hockey Stick" graph.

A version of the "Hockey Stick Graph"., showing temperatures more or less stable for the past millenium, and then sharply spiking upwards in the modern era. After IPCC TAR WG1 (2001) Figure 5. 

The subject of the talk, however, is "The Past as Prologue". Dr. Mann will review work over the past decade aimed at establishing the nature of, and factors underlying, patterns of large-scale climate variability in past centuries.  He will discuss evidence from proxy climate reconstructions spanning the past millennium, the comparison of proxy reconstructions with simulations with climate model simulations forced by past natural and anthropogenic forcing, and results from climate modeling experiments in which proxy evidence is assimilated directly into coupled ocean-atmosphere model simulations. He will also discuss recent work suggesting the possibility that equilibrium climate sensitivity may have been underestimated in some past studies comparing model simulations and paleoclimate reconstructions.

  

This will be a moderately technical talk, which is appropriate since the students that organize the GEOS talks as PhD candidates within the Earth & Environmental Sciences program. However, Dr. Mann has explained that he expects to talk about other issues related to his research. So non-academics are certainly welcome and can expect an exciting talk!

If you can't make it to the Grad Center for the talk, you can also check it out on our livestreaming channel:

http://videostreaming.gc.cuny.edu/videos/channel/44/

Click here for a Flyer with more information (pdf)

(This entry is cross-posted at the GEOS group blog: http://opencuny.org/geos/?p=143)

Dr. S. Pekar on ancient changes in Antarctic Ice Volumes

The first GEOS 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

(This entry is cross-posted at the GEOS group blog: http://opencuny.org/geos/?p=118)