An Improved Dust Storm Prediction System and Its Simulation Experiments

An improved IAP integrated dust-storm prediction system(IAPS 2.0) has been developed at the Institute of Atmospheric Physics(IAP),Chinese Academy of Sciences,through the coupling of the latest version of meso-scale meteorological model(MM5V3.7) with a physical based wind erosion model.The main improvement of IAPS 2.0 over the original IAP dust-storm prediction system(IAPS 1.0) is the substitution of OSU Oregon State University land surface model with the improved Noah land surface model within MM5.Both versions of IAP dust-storm prediction system(IAPS 2.0 and IAPS 1.0) have all been employed to simulate the two typical dust-storm episodes occurred in North China during April 2002.Verification results show that the simulated dust-affected regions by IAPS 2.0 agree quite well with the observation,however,the dust-affected regions simulated by IAPS 1.0 are generally broader than the observation.Further analysis suggests that with the better representation of land surface processes,the simulation of soil moisture by IAPS 2.0 have been significantly improved,and this may lead to the improvement in simulating the threshold friction velocity,which is the key parameter for surface dust emission.In summary,with the incorporation of more advanced land surface model(Noah),the improved IAP dust-storm prediction system(IAPS 2.0) shows better capability in simulating the spring-time dust-storm activities over north part of China.