AAAR 37th Annual Conference October 14 - October 18, 2019 Oregon Convention Center Portland, Oregon, USA
Abstract View
Mobile Measurements to Identify Spatial and Temporal Variability of Aerosol Composition during the NAMaSTE Campaign
Benjamin Werden, Erin Katz, Michael Giordano, Siva Praveen Puppala, Elizabeth Stone, Robert J. Yokelson, Donald Blake, Arnico Panday, PETER DECARLO, Drexel University
Abstract Number: 600 Working Group: Urban Aerosols
Abstract During the Nepal Ambient Monitoring and Source Testing Experiment (NAMaSTE), mobile measurements of aerosol composition were made using a “mini” Aerosol Mass Spectrometer. Fourteen separate drives were conducted in the Kathmandu Valley with the goal of assessing differences in aerosol particle composition over the spatial extent of the valley and at different times of the day. East-west transects of the valley started south of Kathmandu, and proceeded to the ring road, and then east through the peri-urban areas followed by the high brick kiln region of Bhaktapur, and finally to the valley edge in Dhulikhel. North/south transects similarly started at ICIMOD south of Kathmandu, and proceeded North following the ring road and then terminating at the base of the mountains north of the city. These drives captured large differences in concentration and composition of ambient aerosols that can be attributed to strong source emissions that are spatially distinct combined with meteorology directing plumes to some areas of the valley, but not others. Organics were by far the largest contribution to total aerosol particle mass, and showed chemical signatures from primary emissions including traffic, biomass burning and trash burning. Inorganic species such as sulfate and chloride were useful in separating influence from brick kilns, and trash and agricultural burning.