A Tale of Two Basins: Wintertime Air Quality in Utah and the Western United States
CEE Air & Water Seminar Series hosts Dr. Steven Brown, NOAA, October 16, 4 p.m. – 5 p.m., PACCAR 202
Abstract
Although atmospheric chemistry during winter is generally less well studied than its summertime counterpart, recent experience in the western United States has led to an increased interest in wintertime air quality issues. The unusual and recently discovered phenomenon of high winter ozone pollution has followed rapid oil and gas development in mountain basins of Wyoming and Utah. Aerosol pollution in urbanized mountain basins of the western U.S. is a more longstanding problem, but also one that has not necessarily responded to urban emissions reductions in the same way that summertime air pollution has in recent decades. Recent NOAA field studies in two mountain basins of Utah have examined both of these issues. The Uintah Basin is a sparsely populated area of northeast Utah with rapid, recent oil and gas development and extreme winter ozone. NOAA field studies across three recent winters there have identified the cause of winter ozone as well as the similarities and differences with more conventional, summertime urban ozone. The Salt Lake City area has well known winter aerosol pollution, comprised principally of ammonium nitrate. A recent NOAA twin otter study there has provided some of the first aircraft data to understand winter aerosol pollution. The contrast between these regions, their emissions, and the response of the atmospheric chemical system during stagnant meteorological conditions provides new insights into wintertime atmospheric chemistry.
Biography
Dr. Steven S. Brown received a Ph. D. in chemical physics with Professor Fleming Crim at the University of Wisconsin-Madison. He came to NOAA in 1997 as an NRC post-doctoral fellow working with Dr. A. R. Ravishankara, was a Research Scientist with CIRES at the University of Colorado from 2000 – 2005, and has served as a federal Research Chemist since then. His major research theme at NOAA has been the chemistry and impacts of nitrogen oxides in the Earth’s atmosphere. His initial research was on laboratory studies of stratospheric nitrogen oxide kinetics; more recently his focus has been on field measurements of tropospheric nitrogen oxides, particularly those that occur in the dark (“nighttime chemistry”). His other main research interest has been the development of high sensitivity optical instrumentation for laboratory and field studies of atmospheric trace gases and aerosols.
