Solar Spectral and Infrared Radiative Forcing of Aerosol Particles, Aerosol-Cloud Interactions, and Surface Albedo Characterizations

The long-term goal of this research is to improve knowledge of aerosol radiative processes and their influence on climate and to facilitate the remote sensing of aerosol radiative properties from space to achieve global coverage through measurements of the spectrally resolved net solar irradiance over urban/industrial/agriculture centers in southern and central California in the 2010 CalNex field program. A Solar Spectral Flux Radiometer (SSFR) and infrared pyrgeometers will be deployed on the NOAA WP-3D aircraft to measure the upwelling and downwelling solar spectral irradiance and broadband infrared irradiance at various flight altitudes above and below clouds layers and aerosol and haze layers. A second SSFR and CG4 will be deployed on the NOAA Ship Ron Brown to measure the downwelling solar spectral irradiance, zenith radiance, and downwelling infrared irradiance at the surface. These observations will be used to: retrieve cloud properties that can be used to quantify the indirect effect of aerosol radiative forcing; quantify the solar spectral radiative energy budget in regions under the influence of industrial/urban pollutants; determine the solar spectral absorption in atmospheric layers; relate findings to the chemical and physical properties of the aerosol; compare findings to other in situ and remote sensing methods of measuring absorption. A secondary goal of the proposed research is post-mission processing, final archival, and analysis of the following ARCPAC and ICEALOT measurement variables: WP-3D solar spectra upwelling and downwelling irradiance; infrared broadband upwelling and downwelling irradiance; Knorr shipboard downwelling solar spectral irradiance, zenith spectral radiance, and downwelling infrared broadband irradiance. The data will be analyzed using state-of-the-art radiative transfer models that simulate instrument functions, spectral range, and resolution. Analysis objectives will be to quantify atmospheric layer radiative absorption, retrieve cloud and aerosol properties, determine surface spectral albedo, compare measured with modeled radiative perturbations due to aerosols and clouds, and validate satellite observations and retrievals.