Indirect Determination of Integrated Chlorine and Bromine Concentration from Hydrocarbons in Barrow, Alaska

SUCIU, LOREDANA G. , M.S., June 2007, Environmental Studies INDIRECT DETERMINATION OF INTEGRATED CHLORINE AND BROMINE CONCENTRATION FROM HYDROCARBONS IN BARROW, ALASKA (125 pp.) Director of Thesis: Valerie L. Young This research investigates halogen chemistry near Barrow, Alaska at polar sunrise. Other researchers have previously shown that in the Arctic at polar sunrise, chlorine (Cl) and bromine (Br) are directly involved in hydrocarbon depletion, ozone depletion, and the conversion of gas-phase elemental mercury to reactive forms prone to local deposition. Concentrations of Br and Cl at polar sunrise have previously been inferred from hydrocarbon measurements at other Arctic sites. However, such studies have not been conducted at Barrow, a location suspected to have unusually high concentrations of bromine-susceptible hydrocarbons. In this work, hydrocarbon measurements at Barrow, Alaska during February – April 2005 are reported. This is the most comprehensive study hydrocarbon concentrations reported for this important polar research study site. Unusually high concentrations of bromine-susceptible hydrocarbons were not found. Time-integrated concentrations of Br and Cl were inferred from the hydrocarbon measurements. The slow and regular hydroxyl radical (OH) kinetics is discussed. Calculated air back trajectories are displayed with Geographical Information Systems layers to visualize air mass transport during sampling days. Approved: _____________________________________________________________ Valerie L. Young Associate Professor of Chemical and Biomolecular Engineering Acknowledgments I would like to express my deeply gratitude to Dr. Valerie Young for offering me the great opportunity to be involved with such an important project; for sharing the inestimable experience of research in atmospheric chemistry, gas chromatography, and statistics; for the tremendous support, financial and professional, I have received so I can pursue the master degree; for understanding and remarkable mentoring that she has continuously granted me; for constructive criticism, for kindness, for all the time we spent together and for wonderful person that she is I will be always grateful. My thesis wouldn’t be complete without the advising support from Dr. Kevin Crist, as a professor of atmospheric chemistry, as an important committee member, and as a director of the air quality monitoring site, from where I have taken samples for my project and where I have received training in air quality monitoring. Many thanks I wish to address to Dr. Ronald Isaac, who assisted my thesis proposal defense and pointed out the importance of meteorological conditions for my data interpretation. I wish to thank Dr. Jefferson Ueland who reinforced the advisory support for my thesis through important applications of Geographical Information Systems. As a professor of GIS he encouraged me to explore the GIS principles and applications, in particular in modeling and spatial analysis, which unexpectedly became one of my new research fields. I appreciate the amazing support from Dr. Gene Mapes, as a Director of Environmental Studies at the time when I became an MSES student. Thank you for believing in my potential and for guiding through my new major. I would also like to thank Dr. Michele Morrone, the actual Director of Environmental Studies, who continues the guiding through the final steps of my study program. This project wouldn’t be possible without the extraordinary aid from Dr. Paul Shepson from Purdue University and his research team. Thank to Adam Keil, a graduate student of Purdue University, who carried out the air sampling for my thesis project at Barrow, Alaska in 2005. I am also thankful for sharing the ozone data; it was really indispensable for data analysis. Special thanks to Dr. Margaret Pierce from Geography Department, for suggestions to improve the map design of air flow regime at Barrow. I would like to thank James Steiner, a Physics graduate, who helped for this project with standard gas runs. In the same context, I wish to thank Charlotta Fields, a Chemical and Biomolecular Engineering undergraduate student, for plotting chromatogram results to check the consistency in sample runs. I am also expressing my appreciation to several Ohio University students and friends for suggestions, recommendations, criticism, and encouragement: Fei Gao, Seemantini Deshpande, Myoungwoo Kim, Purusha Egilda Bonnin, Ana Mojica, Crina Maria Orac, Violeta Iancu, Catalin Matei and Daniel Sayre. My gratefulness channels towards my family for unconditional support and understanding that fueled my motivation to accomplish this goal. I am also thinking of my friends at home and all over the world for their encouragement and for keeping our friendship strong over time. Thank the Ohio University Graduate Admission Committee for the honor of being accepted to study here. It is an astonishing academical environment opened to learning, experiencing, researching, exploring and interacting with outstanding teachers and students. 6 Table of