Prof. Ken Golden of the Department of Mathematics at the University of Utah will present a series of three Houghton Lectures on the topics of sea ice and climate (May 11), modeling ice process and feedbacks (May 14), and monitoring the response of sea ice to climate change (May 15). Abstract: The polar sea ice packs are key components of the climate system and are critical indicators of climate change. As our climate has warmed up, the precipitous decline of the summer Arctic ice pack is probably the most visible, large scale change on the planet's surface over the past decade. As a material, sea ice is a composite of pure ice with brine inclusions hosting extensive algal and bacterial communities which support life in the polar oceans. In terms of the processes relevant to climate and ecosystem modeling, sea ice displays composite structure on length scales ranging from sub-millimeter to hundreds of kilometers.

In the first lecture, I will give an introduction to sea ice structure, properties, and processes which are relevant to modeling climate change and the microbial communities living in sea ice. In the second lecture, the focus shifts to mathematical approaches to characterizing the composite structures exhibited by sea ice. I'll address the fundamental issue of how smaller scale information can be used to model larger scale processes, such as fluid and thermal transport through the ice, and ice-albedo feedback. In the third lecture, I'll consider the problem of remote sensing and electromagnetically monitoring the properties of sea ice and its response to climate change, where again multiscale considerations are essential.

Over the course of these lectures, I will describe how advances can be made using the mathematics of forward and inverse homogenization for composites, percolation theory, diffusion processes, and statistical mechanics, to understand the role of sea ice in the climate system. I will also discuss my field work on measuring fluid and electrical transport processes in the Arctic and Antarctic ice packs. Sea ice structure and processes will be illustrated with video taken during my Antarctic expeditions. (Prof. Golden's website.)

The Houghton Lectures are sponsored by the Program in Atmospheres, Oceans and Climate (PAOC) in the Department of Earth, Atmospheric and Planetary Sciences.