Column total sulfate aerosol from natural source is estimated from total and anthropogenic sulfate mass distribution (the data available at http://gacp.giss.nasa.gov/transport/) derived by the GACP transport model by Tegen et al. (1997). The geographical distributions for annual-mean and monthly are shown below. The aerosol mass in the column is vertically distributed with a homogeneous mixing ratio in the lowest 740 m thickness of the atmosphere.
Annual mean distribution of column total sulfate mass loading (unit: 10-3 gm-2) from natural source.
Monthly distributions of column total sulfate mass loading (unit: 10-3 gm-2) from natural source.