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AbstractLarge-scale dust storms originated at the Northeastern Chine frequently occurduring springtime. Some of the elevated dust particle may be transported longdistance through atmospheric circulation to the Taiwan area. The possibly effects ofthese atmospheric dust particles include the influence on public health, lowering thevisibility and even causing aviation safety concerns, reducing solar radiation to thesurface, and altering the precipitation processes. Due to its increasing frequency ofoccurrence during the past decade, it is essential to study the mechanisms controllingthe transport of yellow dust to Taiwan, and develop forecasting capability for earlywarning. The elevation and transport of atmospheric dust particles is controlled bythe surface conditions of the source region (deserts) and the regional weather patterns.The goal of this study is to develop an modeling system that can accurately simulationthe elevation of dusts as well as their subsequent transport in the regional scales, andto help establishing an early-warning system for the Environmental Protection Agencyfor alerting the public regarding to their health, and to provide lead time of operationfor the dust-sampling group and health effect evaluation group.The accomplishments of this project include: (1) development of dust stormforecasting models suitable for use in the East Asia region and Taiwan area, thisinclude a TAQM/dust model and NAQPM/dust model; (2) daily watch of the duststorm events by analysis of the synoptic weather patterns and observation datarelevant to Asia dust storms; (3) evaluation of the time, duration, area extent andconcentration of possible events of dust reaching Taiwan, so as to assist the issue ofwarnings by the operation center of EPA; (4) built a web site of atmospheric dustforecasting, using calendar-style data bank in exhibiting the movies of dust stormsimulation and analysis data.Among the 7 significant and 2 minor dust events occurred during the Spring of2002, our forecasting model missed one of the event and false-alarmed the other.The false-alarm case was an event with strong rain scavenging effect, which was notconsidered in the TAQM/dust model at the time. Improvement has been made toinclude this rainout mechanism. For the event that was missed by the model, anerror in coding was made when modifying the model, such that the event was actuallycaptured but the order of dust concentration was wrong and is thus counted as amissed case. Corrections have been made soon after. For the rest of the events, theforecasting model did fairly well on the arrival time, duration, and area extent, but notas satisfactory in the maximum mass concentrations. An overall evaluation of theperformance of our and foreign models was made, and we found that the TAQM/dustmodel is superior to all other models in forecasting dust events in Taiwan.Key words: Dust storm; atmospheric dust model, Taiwan Air Quality Modeiv