Stratospheric Aerosol Data Assimilation for Climate Studies

Rutgers University New Brunswick, New Brunswick NJ

Investigators

Abstract

The PIs will develop a data assimilation system for stratospheric aerosols based on the new generation NASA finite volume Data Assimilation System (fvDAS) to produce a global stratospheric aerosol data set for the extended time period of the stratospheric aerosol and gas experiment (SAGE) observations suitable for climate studies. They will account for the physical mechanisms of aerosol transport and microphysical transformations, and tune the fvDAS for assimilating satellite, lidar, balloon, and mission observations. Dynamically-consistent 3-D spatial distributions of aerosol extinction, single scattering albedo, asymmetry parameter, backscattering coefficient, and phase function will be calculated. The study will focus on the 25-year period from 1979 to the present covering the effects of two of the largest volcanic eruptions of the 20th century, El Chichon and Pinatubo. To exercise and validate the new data set, they will calculate radiative forcing caused by volcanic aerosols and study the effect of volcanic eruptions on decadal climate change. They will quantify their contribution to the observed positive trend of the Arctic Oscillation. The calculated aerosol data set and aerosol radiative forcing will be made available for climate and chemistry studies. Broader impacts of this project will support the education of one graduate student. The project will develop new research collaborations between Rutgers University, the NASA Langley Research Center, the NASA Goddard Space Flight Center, the University of Colorado, and San Jose State University. The results will be disseminated electronically on the Worldwide Web and will produce a better understanding of the mechanisms of observed climate change and will improve the quantification of the volcanic effect on climate, clearly of benefit to society.