Kris Hajny: Shepson Atmospheric Chemistry Group: Purdue University

Kris Hajny

Kris Kris joined the Shepson lab in 2015 after receiving his B.S. in Chemistry and Sustainability Science from Furman University in South Carolina. His work in the Shepson lab focuses on improving our understanding of the emissions of the greenhouse gasses CO2 and CH4 from urban areas and power plants using the Airborne Laboratory for Atmospheric Research (ALAR) .

Kris finished his graduate studies at Purdue University in the Shepson lab and now works as a postdoctoral research associate in the lab. His graduate research focused on better understanding potential methane (CH4) emissions from incomplete combustion at natural gas – fired power plants. CH4 is a greenhouse gas >80 times as potent as carbon dioxide (CO2) in the short term and natural gas/petroleum systems are responsible for the majority of CH4 emitted in the U.S. as natural gas itself is >90% CH4. As power plants are required to report CO2 emissions, these power plant flights also provide a valuable opportunity to compare measured CO2 emissions to the reported values as a test of the airborne method's performance.

Lastly, his graduate research also included emission quantification over urban environments. Urban areas are responsible for ~40% of CO2 emissions across the contiguous United States and quantifying emissions is crucial to track progress as cities enact laws to reduce emissions. This work focused on New York City (NYC) as the city recently passed several laws aimed at considerably reducing emissions. The method of interest is a type of inventory scaling method that more appropriately focuses on NYC. These approaches use transport modeling to relate the emission inventory to airborne measurements downwind, allowing us to adjust the inventory to best match measurements.

His postdoctoral research is focused on two new projects. Following up on the NYC work, he is now preparing the >70 flights that ALAR has flown over Indianapolis since 2008 for inversion analyses. With such a long running dataset we hope to investigate any trends in emissions and quantify the minimum trend that could be detected with this approach. His other project is CHemistry in the Arctic: Clouds, Halogens, and Aerosols (CHACHA). This work involves 2 months of fieldwork with 2 aircraft in Alaska.

email: kristian.hajny@stonybrook.edu