AAAR 31st Annual Conference
October 8-12, 2012
Hyatt Regency Minneapolis
Minneapolis, Minnesota, USA
Abstract View
The Complex Role of Vegetation in Mitigating Near Road Air Pollution
ZHEMING TONG, Max Zhang, Patrick MacRae, Thomas Whitlow, Cornell University, Ithaca, NY, USA
Abstract Number: 508 Working Group: Health Related Aerosols
Abstract Air pollution is a major environmental concern in cities across the world. Urban vegetation may help mitigate local particulate pollution. We conducted a near-road study to investigate the impact of vegetation barriers next to a major highway in New York City. Three real time optical particle counters were placed next to the highway, behind a vegetated buffer, and in the open field. Particle number size distributions were measured from 0.3 µm to 20 µm. Average PM2.5 concentration declined with distance from the road. The particle concentration was lowest in the open field 34 meters downwind of the barrier. Vegetation did little to attenuate transient spikes caused by traffic and acted as a “low pass” filter by reducing the number of low concentration events. In addition, the gradient in particle concentration away from the road was strongly dependent on wind velocity and direction, where greater concentration usually corresponded to lower wind speed and wind directions that are more perpendicular to the highway.