News & Events - 2017
CSD Receives OAR Outstanding Scientific Paper Award and CIRES IRP Grant9 June 2017
CSD has received an OAR Outstanding Scientific Paper Award and a grant from the CIRES Innovative Research Program (IRP).
OAR Outstanding Scientific Paper Award
OAR restarted the Outstanding Scientific Paper Award this year after a few off-line years with only 5 of 25 nominated papers receiving an award. Our selected paper presents the chemical mechanism underlying the large wintertime ozone increases observed in the Utah Uintah Basin oil and gas region. It is a tour de force showcasing our skills in instrumentation, measurement strategy, the interpretation of atmospheric chemical observations, and working with stakeholders to diagnose and describe a complex and unexpected chemical phenomenon. Success in reaching this understanding required a multi-year effort by the large author group. Pete Edwards, a former CIRES scientist at CSD, is the first author and currently at the University of York. Steve Brown will accept the award and speak about the paper at the OAR awards ceremony on June 16 at the NOAA Auditorium in Silver Spring.
The nomination stated "This study solved the enigma of exceptionally high wintertime ozone concentrations discovered in a sparsely populated Western oil and gas production region, one suffering from an air quality problem previously associated only with summertime densely populated urban areas. The innovation in this study is that the author team recognized the salient features of the problem, identified the approach needed to resolve it, partnered with stakeholders and industry to carry out the necessary measurements, and persevered over three years of remote wintertime field work to collect critical data to fully characterize these episodes. The authors used their targeted chemical and meteorological measurements and a sophisticated atmospheric model to show definitively that this wintertime ozone came from the combination of large oil and gas emissions reacting for days at a time in a meteorologically-isolated basin, with snow on the ground acting to accelerate the chemical reactions leading to ozone formation. This study lays to rest more exotic and conjectural explanations for high ozone concentrations, and further has led to a predictive understanding not available previously that has been used by the Utah Department of Environmental Quality to draft effective and scientifically sound emissions control measures."
Citation: Edwards, P.M., S.S. Brown, J.M. Roberts, R. Ahmadov, R. Banta, J. de Gouw, W.P. Dube, R.A. Field, J. Flynn, J. Gilman, M. Graus, D. Helmig, A. Koss, A.O. Langford, B. Lefer, B. Lerner, R. Li, S.-M. Li, S. McKeen, S. Murphy, D. Parrish, C.J. Senff, J. Soltis, J. Stutz, C. Sweeney, C. Thompson, M.K. Trainer, C. Tsai, P. Veres, R.A. Washenfelder, C. Warneke, R.J. Wild, C.J. Young, B. Yuan, and R. Zamora, High winter ozone pollution from carbonyl photolysis in an oil and gas basin, Nature, doi:10.1038/nature13767, 2014.
The United States is now experiencing the most rapid expansion in oil and gas production in four decades, owing in large part to implementation of new extraction technologies such as horizontal drilling combined with hydraulic fracturing. The environmental impacts of this development, from its effect on water quality to the influence of increased methane leakage on climate, have been a matter of intense debate. Air quality impacts are associated with emissions of nitrogen oxides (NOx = NO + NO2) and volatile organic compounds (VOCs), whose photochemistry leads to production of ozone, a secondary pollutant with negative health effects. Recent observations in oil- and gas-producing basins in the western United States have identified ozone mixing ratios well in excess of present air quality standards, but only during winter. Understanding winter ozone production in these regions is scientifically challenging. It occurs during cold periods of snow cover when meteorological inversions concentrate air pollutants from oil and gas activities, but when solar irradiance and absolute humidity, which are both required to initiate conventional photochemistry essential for ozone production, are at a minimum. Here, using data from a remote location in the oil and gas basin of northeastern Utah and a box model, we provide a quantitative assessment of the photochemistry that leads to these extreme winter ozone pollution events, and identify key factors that control ozone production in this unique environment. We find that ozone production occurs at lower NOx and much larger VOC concentrations than does its summertime urban counterpart, leading to carbonyl (oxygenated VOCs with a C = O moiety) photolysis as a dominant oxidant source. Extreme VOC concentrations optimize the ozone production efficiency of NOx. There is considerable potential for global growth in oil and gas extraction from shale. This analysis could help inform strategies to monitor and mitigate air quality impacts and provide broader insight into the response of winter ozone to primary pollutants.
CIRES Innovative Research Program (IRP) grant
CSD has a very successful history with the CIRES Innovative Research Program (IRP). Drew Rollins and Shuka Schwarz were awarded a grant this year. Their innovative project is an exciting challenge for CSD since it will involve attempting to measure a very trace species, atomic chlorine (Cl), which has never been directly observed but is expected to play an important role in atmospheric chemistry.
IRP: Direct spectroscopic detection of tropospheric chlorine radicals
Investigators: Andrew Rollins, Joshua Schwarz
The extremely reactive chlorine radical contributes to many important chemical processes in the troposphere, including loss of ozone in the Arctic boundary layer, production of ozone in polluted regions, oxidation of mercury, removal of methane and other organic compounds, and formation and aging of secondary organic aerosols. To date, there has been no demonstrated direct method for quantifying the concentrations of these radicals. CIRES research scientist Andrew Rollins and NOAA research physicist Joshua Schwarz propose a unique method for solving this problem. Instead of estimating chlorine (Cl) radical concentration using measurements of other species (which might underestimate or overestimate Cl), the research team plans to build a prototype instrument that uses two photons to sequentially excite Cl from the ground state and then detects blue-shifted fluorescence on a zero background. Such an instrument would help scientists directly verify the existence of this species, quantify its highly variable concentrations, and constrain the possibility of yet-unidentified chemistry. This would enable significant advances in the study of tropospheric reactive halogen processes, and help reveal anthropogenic changes to this region of the atmosphere.