1. Tracking DMS in Antarctica Burton Gray December 1, 2004

2. Oxidizing Boundary Layer Mixed Layer Once Thought to be Chemically Inert Mixed Layer Once Thought to be Chemically Inert Large Levels of Nitric Oxide Present Large Levels of Nitric Oxide Present Leads to Formation of OH Leads to Formation of OH Reacts with Chemical Species in the Mixed Layer and the Snowpack Reacts with Chemical Species in the Mixed Layer and the Snowpack Can Bias Results from Glacio-Chemists Can Bias Results from Glacio-Chemists

3. Importance of DMS Released by Phytoplankton from Southern Ocean Released by Phytoplankton from Southern Ocean Chemical Indicator of Biomass Production Chemical Indicator of Biomass Production Could Provide Valuable Information in Studying Past Climate Changes Could Provide Valuable Information in Studying Past Climate Changes

4. Measuring DMS 2000-2001 Study from Davis, et al 2000-2001 Study from Davis, et al –Expected significant atmospheric transport of DMS and sulfate from coast to pole (10kft alt) –Found very little unreacted DMS at Pole Elevated NO Maintains Highly Oxidizing Environment Elevated NO Maintains Highly Oxidizing Environment –Order of magnitude greater than that found in Summit, Greenland and Alert, Canada

5. Tracking DMS Use 2000 Data Use 2000 Data Code Developed by Tao Zeng Code Developed by Tao Zeng Backtracking Through x-Day Increments Backtracking Through x-Day Increments Compare DMS versus Other Chemical Species Levels at Each Point Along the Way Compare DMS versus Other Chemical Species Levels at Each Point Along the Way

6. My Results Available Data: 11/09/00  12/31/00 Available Data: 11/09/00  12/31/00 Range I Chose: Range I Chose: –11/25/00  12/10/00 –Five-Day backtracking Backtracking Based on Meteorological Data Only Backtracking Based on Meteorological Data Only No Chemical Species Breakdown No Chemical Species Breakdown

7. My Results

9. Future Work Experiment More with Number of Backtracking Days Experiment More with Number of Backtracking Days Perform Chemical Species Breakdown at Each Location to Isolate DMS Perform Chemical Species Breakdown at Each Location to Isolate DMS Will Hopefully Lead to Better Understanding of DMS Trajectory and Influence Will Hopefully Lead to Better Understanding of DMS Trajectory and Influence