NATIVE Catches Some WAVES in Beltsville, MD: Apportioning Sources From a Suburban Forest During WAVES, July 2006

NATIVE (Nittany Atmospheric Trailer and Integrated Validation Experiment) is a mobile research facility designed for air quality and satellite validation studies. In July of 2006, NATIVE participated in WAVES (Water Vapor Validation Experiment - Satellite/Sondes) at the Howard University Beltsville, MD campus. The campus, located between Washington, D.C. and Baltimore, MD in a 100 acre forested lot, lies at the intersection of urban and rural influences in a "suburban forest," a landscape that is representative of the trend in U.S. development. A complex mixture of sources, including industrial, mobile, and agricultural, influences the air quality at the site. Additionally, the forested suburban setting allows for the differentiation between anthropogenic and biogenic impacts to local air quality. NATIVE, located adjacent to an air quality monitoring facility of the Maryland Department of the Environment (MDE) and a 31 m flux tower, measured in-situ trace gases (CO, O3, NO, NOy, and SO2), vertical aerosol backscatter and extinction with a 532 nm lidar, aerosol optical thickness and column ozone with a UV shadowband radiometer, and meteorological parameters (T, RH, P, WS, and WD) from a 10 m tower on a continuous basis during the campaign. Comparisons between the NATIVE and MDE in-situ trace gas measurements agreed well (O3 r2 = 0.997; slope = 0.98). Multiple pollution episodes were observed during the campaign (O3 up to 116 ppb; 2 "code red" 8 h avg. days). We present an initial apportionment of the various pollution sources that impacted the Beltsville, MD site during WAVES, based on observations from NATIVE and complementary measurements.