Large Contribution of Coarse Mode to Aerosol Microphysical and Optical Properties: Evidence from Ground-Based Observations of a Transpacific Dust Outbreak at a High-Elevation North American Site

Journal Article · Mon Apr 17 00:00:00 EDT 2017 · Journal of the Atmospheric Sciences

DOI:https://doi.org/10.1175/JAS-D-16-0256.1· OSTI ID:1351708

Kassianov, E. ^[1]; Pekour, M. ^[1]; Flynn, C. ^[1]; Berg, L. K. ^[1]; Beranek, J. ^[1]; Zelenyuk, A. ^[1]; Zhao, C. ^[1]; Leung, L. R. ^[1]; Ma, P. L. ^[1]; Riihimaki, L. ^[1]; Fast, J. D. ^[1]; Barnard, J. ^[2]; Hallar, A. G. ^[3]; McCubbin, I. B. ^[3]; Eloranta, E. W. ^[4]; McComiskey, A. ^[5]; Rasch, P. J. ^[1]

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1. Pacific Northwest National Laboratory, Richland, Washington
2. University of Nevada, Reno, Nevada
3. Storm Peak Laboratory, Desert Research Institute, Steamboat Springs, Colorado
4. University of Wisconsin–Madison, Madison, Wisconsin
5. National Oceanic and Atmospheric Administration, Boulder, Colorado

This work is motivated by previous studies of transatlantic transport of Saharan dust and the observed quasi-static nature of coarse mode aerosol with a volume median diameter (VMD) of approximately 3.5 μm. In this work, the authors examine coarse mode contributions from transpacific transport of dust to North American aerosol properties using a dataset collected at the high-elevation Storm Peak Laboratory (SPL) and the nearby Atmospheric Radiation Measurement (ARM) Mobile Facility. Collected ground-based data are complemented by quasi-global model simulations and satellite and ground-based observations. The authors identify a major dust event associated mostly with a transpacific plume (about 65% of near-surface aerosol mass) in which the coarse mode with moderate (~3 μm) VMD is distinct and contributes substantially to total aerosol volume (up to 70%) and scattering (up to 40%). The results demonstrate that the identified plume at the SPL site has a considerable fraction of supermicron particles (VMD ~3 μm) and, thus, suggest that these particles have a fairly invariant behavior despite transpacific transport. If confirmed in additional studies, this invariant behavior may simplify considerably parameterizations for size-dependent processes associated with dust transport and removal.

• Research Organization: Pacific Northwest National Laboratory (PNNL), Richland, WA (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Biological and Environmental Research (BER)
• Grant/Contract Number: AC05-76RL01830
• OSTI ID: 1351708
• Alternate ID(s): OSTI ID: 1353321
• Report Number(s): PNNL-SA-118075
• Journal Information: Journal of the Atmospheric Sciences, Journal Name: Journal of the Atmospheric Sciences Vol. 74 Journal Issue: 5; ISSN 0022-4928
• Publisher: American Meteorological Society
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
Dust or dust storms
Optical phenomena
Precipitation
In situ atmospheric observations
Lidars/Lidar observations
Surface observations