AAAR 37th Annual Conference October 14 - October 18, 2019 Oregon Convention Center Portland, Oregon, USA
Abstract View
Adsorption of VOCs by Airborne Dust Particles in the Semi-Arid Forest Canopy
BORIS KRASOVITOV, Andrew Fominykh, Itzhak Katra, Avi Levy, Andrey Khlystov, Ben-Gurion University of the Negev, Israel
Abstract Number: 219 Working Group: Remote and Regional Atmospheric Aerosol
Abstract Volatile organic compounds (VOCs) are naturally occurring chemicals that are highly volatile and thus found predominantly in the gas phase in the atmosphere. The mineral dust particles interact with VOCs emitted from a trees’ leaves. Dust storms may significantly affect the concentration of VOCs in the atmosphere due to adsorption of VOCs by airborne dust particles. The developed model considers the interaction between the forest structure, open field and forest aerodynamics, aerosol and VOCs characteristics. Two-dimensional model is based on the application of theory of turbulent diffusion in the forest canopy in conjunction with models of VOCs release by leaves and gas adsorption by porous solid particles. The model of dust transport in the forest canopy is validated by comparison of theoretical results with measured dust concentrations. Measurements were conducted along a forest located in a semi-arid region (Northern Negev, Israel) to record PM concentrations in the forest and nearby environments during dust storms. The measurement results showed that during medium- and high-level dust storms, PM10 concentrations in an urban environment that is located at the leeward side of the forest can be reduced by 28% compared with those of a nearby urban environment that is not affected by forest. Calculations performed using the developed model showed that despite a significant decrease in the PM concentration along the forest, dust particles can reduce the concentration of VOC by 7-10 % on the leeward side of the forest.