AAAR 32nd Annual Conference
September 30 - October 4, 2013
Oregon Convention Center
Portland, Oregon, USA
Abstract View
Secondary Pollutant Formation in the Lake Tahoe Basin, USA
BARBARA ZIELINSKA, Andrzej Bytnerowicz, Alan Gertler, Mark McDaniel, Joel Burley, Desert Research Institute
Abstract Number: 444 Working Group: Carbonaceous Aerosols in the Atmosphere
Abstract Lake Tahoe, located at 6,225 ft. (1,897 m) in the Sierra Nevada mountain range, is the largest alpine lake in North America. Known for the clarity of its water and the panorama of surrounding mountains on all sides, Lake Tahoe is a prime tourist attraction in the California – Nevada area. However, the Lake Tahoe Basin is facing significant problems in air quality and declining water clarity.
In the summer of 2012, we conducted a study in the Basin designed to characterize the precursors and pathways of secondary pollutant formation, including ozone, secondary organic aerosol (SOA) and ammonium nitrate. Four strategic sampling sites were selected inside the Basin; two of these sites were located at high elevation (one each on the western and eastern sides of the Basin) and two were positioned near the Lake level. We collected canister samples for detailed speciation of volatile organic compounds (VOC), 2,4-dinitrophenylhydrazine (DNPH) impregnated Sep-Pak cartridges for analysis of carbonyl compounds and honeycomb denuder/filter pack samples for measurement of concentrations of ammonia, nitrous acid, nitric acid, and fine particulate ammonium nitrate with a resolution of several hours over a 6-day sampling period. We also collected PM$_(2.5) Teflon and quartz filter samples for measurements of mass, organic and elemental carbon (OC/EC) concentrations and speciation of organic compounds. Ozone and NO/NO$_2 concentrations were continuously measured.
This presentation will discuss concentrations of volatile biogenic and anthropogenic secondary pollutant’s precursors in the Basin and relate these concentrations to the measured SOA tracers.