A23F-0395
What Can AMF Observations Tell Us about Super-micron Particles?
Tuesday, 15 December 2015
Poster Hall (Moscone South)
Evgueni Kassianov1, Mikhail S Pekour1, Connor Joseph Flynn2, Larry K Berg1, Josef Beranek1, Alla Zelenyuk1, James Barnard3, Anna Gannet Hallar4, Allison C McComiskey5 and Philip J Rasch1, (1)Pacific Northwest National Laboratory, Richland, WA, United States, (2)PNNL, Richland, VA, United States, (3)University of Nevada Reno, Reno, NV, United States, (4)Desert Research Institute, Reno, NV, United States, (5)NOAA Boulder, Boulder, CO, United States
Abstract:
While numerous studies have demonstrated a significant contribution of super-micron particles to the total aerosol mass for many regions with large aerosol loading, comparatively little is known about the importance of these particles in relatively clean areas common to much of the globe. To investigate their potential importance, we take advantage of datasets collected from ground-based observations during recent field campaigns supported by the Department of Energy (DOE) Office of Science Atmospheric Radiation Measurement (ARM) and Atmospheric System Research (ASR) Programs. These campaigns were designed to provide a comprehensive dataset that can be used to investigate important climate science questions, including those related to aerosols, for many regions around the world using the unique capabilities of the ARM Mobile Facility (AMF; http://www.arm.gov/sites/amf). The AMF datasets integrate observations from numerous instruments for sampling aerosol and cloud and radiative properties, including the Multi-Filter Rotating Shadowband Radiometer (MFRSR), a Scanning Mobility Particle Sizer (SMPS), an Aerodynamic Particle Sizer (APS), a three-wavelength nephelometer, and a Single Particle Mass Spectrometer (SPLAT II). The latter was used to characterize the size, composition, and density of individual particles in the size range from 50 to 3,000 nm. We analyze column and near-surface data from these instruments to explore the possible importance of super-micron particles to aerosol microphysical and optical properties. We find that their contribution to the climate-relevant total scattering and absorption can be quite large (50% and 30%, for scattering and absorption, respectively). These large contributions occur even in areas with low-to-moderate aerosol loading (total scattering < 50 Mm-1) located far from major sources. We discuss the expected implications from our results to the evaluation and improvement of regional and global climate models.
