Undergrad Eddie Galbavy collects ice samples

Newsletter - Spring 2008

Current Research - Climate Change

Snow photochemistry in Greenland

Summer is usually associated with a hot day at the beach taking in some sun, but Associate Professor Cort Anastasio and his team prefer to spend their time at the frigid top of the Greenland ice sheet. However, they are indeed taking in some sun. In fact, that is what they are there to do.
From 2003 - 2005, Anastasio and a team of post-docs and graduate students went to Summit Camp, Greenland each year to measure snow photochemistry – i.e., the reactions that occur when sunlight hits snow crystals.

Previous research found that sunlight illumination of snow releases a host of trace gases to the atmosphere, including NO, NO2, carboxylic acids, aldehydes, and other hydrocarbons.  These gases are important because they can influence the chemistry and composition of both the atmosphere and the snowpack.  The goal of professor Anastasio’s research is to determine the chemical mechanisms responsible for these releases.
Why Summit, Greenland?   At Summit the snow and ice is approximately two miles thick, providing a record of the snow and atmosphere that reaches back over two hundred thousand years.  “When sunlight hits the snow, it initiates a series of reactions that can affect concentrations of some of the trace species in the snow” explains Anastasio. “We are examining how these reactions alter snow composition and, in turn, the translation of ice core records to infer past atmospheric compositions.”

This may prove to be useful for research in climate change, where careful analysis of changes in the atmosphere’s composition over time is helping researchers understand the influence of human activity on climate. Since returning from Greenland, the Anastasio team has been working in the laboratory with snow from Summit to examine the rates and mechanisms responsible for snow photochemical reactions.