Carbonaceous Aerosols and Radiative Effects Study (CARES) of Sacramento Urban Air Plume Initiated
Carbonaceous Aerosols and Radiative Effects Study (CARES) of Sacramento Urban Air Plume Initiated. On June 1, 2010, DOE’s Atmospheric Radiation Measurement Climate Research Facility began the CARES field study. Using a combination of more than 50 instruments at two ground sites and on two aircraft, the team is measuring the evolution of black carbon and secondary aerosols and their optical and hygroscopic properties in the Sacramento urban air plume as it transports to the northeast regions of the state. The plume is composed of black carbon (BC), urban primary organic aerosols (POA), biomass burning aerosols (BBA), and secondary organic aerosols (SOA) from both urban and biogenic precursors. These constituents play a major role in the direct and indirect radiative forcing of climate. The CARES campaign uses the DOE G-1 (Gulfstream 1) aircraft to sample upwind, within, and outside of the evolving plume. Aircraft measurements are complemented by a well-instrumented ground site in the Sacramento urban source area and a receptor site near Cool, CA, which is approximately 70 kilometers downwind. The CARES campaign strategy is centered on using the data in various focused model evaluation exercises so that the resulting new knowledge can be integrated into regional and global aerosol models.