Special Journal Issue: DOE Atmospheric Research / ARM CARES Campaign
Five papers have been published with four more in review for a special issue on the U.S. Department of Energy (DOE) Carbonaceous Aerosol and Radiative Effects Study (CARES) experiment. The CARES experiment, conducted in June 2010 in Central Valley, California, was a comprehensive effort designed to improve the understanding of the possible interactions between urban and natural (biogenic) emissions in the production and transformation of atmospheric aerosols and the resulting impact on climate change. The field study’s primary objective was to investigate the evolution of secondary organic and black carbon aerosols and their climate-related properties in the Sacramento urban plume as it was routinely transported into the forested Sierra Nevada foothills area. Urban aerosols and trace gases experienced significant physical and chemical transformations as they mixed with the reactive biogenic hydrocarbons emitted from the forest. Two heavily instrumented ground sites-one within the Sacramento urban area and another about 40 km to the northeast in the foothills area-were set up to characterize the evolution of meteorological variables, trace gases, aerosol precursors, aerosol size, composition, and climate-related properties in freshly polluted and “aged” urban air. On selected days, the DOE G-1 aircraft was deployed to make similar measurements upwind and across the evolving Sacramento plume in the morning and again in the afternoon. DOE also supported the NASA B-200 aircraft, which carried remote-sensing instruments, to characterize the vertical and horizontal distribution of aerosols and aerosol optical properties within and around the plume. Preliminary findings from the campaign include expanded insight into the interactions of biogenic and anthropogenic secondary organic aerosols, as well as unexpected behavior of optical and volatility properties of organic aerosols in this region.
Zaveri, R. A., et.al. 2012. “Overview of the 2010 Carbonaceous Aerosols and Radiative Effects Study (CARES),” Atmospheric Chemistry and Physics 12, 1299-1400. DOI: 10.5194/acp-12-7647-2012.