Thetypicalblackstormsorsand-duststormsinthenorthwesternChinaaregeneratedanddevelopedthroughaninteractionbetweenthespecificlargescalecirculationpatternandmesosealesystems.Thepassingby/overahugesand-abundantdesertofastrongcoldfrontwithintensivefrontalzoneatmidandlowerlevelsisanecessaryconditionfortheformationanddevelopmentofablackstormoraseveresand-duststorm.Inordertoinvestigatethemechanismofthesand-dustmobilization,transportandsedimentationduringtheblackorsand-duststorms,aparameterizationschemeofsand-dustsource-sinktermsandanequationoftransportforthesand-dustwereproposedandincorporatedintotheMM4mesoscalemodel.ThemodifiedMM4modelwasappliedtothe“May1993”blackstormcaseandsucceededinreproducingtheevolutionoftheweathersystemsassociatedwiththeblack-storm,thesand-dustconcentrationatsurfacelayeranditsverticaldistribution,andthesand-dustsedimentationandtransport.Ourresultsshowthatthenumericalsimulatingmethodbyusingamesoscalemodel,withinclusionofanequationofthesand-dusttransportandaparameterizationschemeofthesand-dustsource-sinkterms,isapromisingapproachtostudythemechanismforsand-dustmobilization,transportandsedimentationduringasand-duststormevent.
