My research addresses the role of trace gases and aerosols on Earth's climate, atmospheric oxidation, and air quality. We develop instruments for fast-response in situ measurements from the ground, balloons, and aircraft. We  have participated in numerous field campaigns to study topics such as stratospheric ozone depletion over the Arctic, the impact of rockets on stratospheric chemistry, long-range transport of pollutants, and the role of aerosols in modification of cloud properties. We have conducted work in Antarctica, Spitsbergen, New Zealand, Sweden, Nepal, the Virgin Islands, Alaska, Hawaii, and throughout the continental United States.
For more details, see
Google Scholar, on, and ResearchGate

Science Policy
During the 2011-2012 academic year, I served as a Jefferson Science Fellow at the U.S. Department of State in the Bureau of East Asian and Pacific Affairs.  I worked on issues related to energy and green growth for APEC, attended the 10th APEC Energy Ministerial Meeting in St. Petersburg, Russia, and organized an APEC Workshop on Climate Change Adaptation in Singapore.  Many of these issues are featured in the President's Climate Action Plan.  Since returning to CU, I have helped to develop a proposal to ICSU for hosting a hub of the Future Earth Secretariat in the United States. Together with colleagues at CSU,
we will be operating the U.S. global hub of the permanent Future Earth Secretariat here at CU beginning in early 2015. Watch this space for updates!

Photo: 2011 Jefferson Science Fellows with Secretary Clinton
Read: 2014 Jefferson Science Fellowship brochure
Read:  My Year as a Jefferson Science Fellow
Watch: Understanding Climate Change and the Redistribution of Heat, Winds, Water, and Worries
(U.S. Center, Doha Climate Change Conference, November 2012) 
The Canary in the Coal Mine: Why the Stratosphere is Still Relevant (U.S. Dept. of State,  April 2012)

Future Earth News

CU and CSU to host the U.S. Hub of the Future Earth Secretariat
Read More about Colorado's role in this important initiative
Support from Colorado senators and respresentatives

In Fall 2014, I am teaching the graduate course in Atmospheric Chemistry for the first time since I taught a similar course at UC Irvine in the 1990s. This will force me to convert all my hand-written lecture notes to Powerpoint slides...skipping handdrawn transparencies entirely. What a concept!