Start Date/Time: Thursday, April 18, 2013, 3:30 PM
Ending Date/Time: Thursday, April 18, 2013, 4:30 PM
Location: JHN 075
ESS Research Assistant Professor candidate seminar
Speaker: Michele Koutnik
Topic: Imprint of climate and ice flow on ice sheets
Abstract: Measurements of Greenland and Antarctica in response to modern changes in climate and ice flow shows that large ice sheets can undergo rapid changes. While these modern measurements are critical to our understanding, past ice-sheet behavior provides a necessary perspective on modern rapid changes and our understanding of ice-sheet behavior. To infer histories of climate and ice-sheet change, we must understand how changes in climate and ice flow are imprinted on ice-sheet data. How do existing data preserve information about what we want to infer? I will focus on how to infer information about ice sheets in the past by interpreting internal layers and ice-surface topography from Greenland, Antarctica, and the North polar ice cap on Mars.
On Earth, because we know that ice masses flow we can use physically based flow models together with ice-sheet data to understand terrestrial climate and ice-flow histories. While using martian ice-surface topography and internal layers together in order to understand the history of martian ice masses is an important goal, the Mars research community has yet to reach a consensus as to whether the polar ice masses ever flowed. This means that layer and topography data must be interpreted carefully. I will present strong evidence for past flow on the North polar ice cap of Mars, and discuss the implications for past flow in an environment that is presently too cold for significant ice flow.