Numerical Simulation on Climate Characteristics of Global Dust Aerosol Transport Process

Dust-storm events during March and April in 2001 are simulated by a global aerosol transport model (MATCH) coupled with the Dust Entrainment and Deposition Model (DEAD). The results show that the simulated dust sources and transmission paths in spring agree with observation. Analysis of dust emission and deposition shows that dry deposition process is the major mode for the decrease of dust concentration, and the turbulence settling amount is greater than the gravitational deposition. Wet deposition is the fundamental mode to affect the regions far away from dust source area. As for global dust storm, the size of the dominant dust particles is 1~2.5 mum, and particles of 0~1 mum and 2.5~5 mum take the second place. However, the size of dominant dust particles over China is 1~2.5 mum, 2.5~5 mum and 5-11 mum. Dust particles of 0~1 mum have little contribution to total dust emission. Comparison of simulated result and EP-TOMS aerosol index also shows that the MATCH&DEAD coupled model has well simulation performance on the characteristics of synoptic-scale dust-storm events.