1. 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.
- Author
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Kassianov, E., Pekour, M., Flynn, C., Berg, L. K., Beranek, J., Zelenyuk, A., Zhao, C., Leung, L. R., Ma, P. L., Riihimaki, L., Fast, J. D., Barnard, J., Hallar, A. G., McCubbin, I. B., Eloranta, E. W., McComiskey, A., and Rasch, P. J.
- Subjects
ATMOSPHERIC aerosols ,DUST ,MICROPHYSICS ,OPTICAL properties ,ATMOSPHERIC radiation measurement ,PLUMES (Fluid dynamics) - Abstract
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. 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. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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