The blowing dust from the normally arable land can be transported downwind to an extensive area. In those areas the observed amount of PM10 and PM2.5 increased to a certain degree. In United States weather observing practice it considered as a severe weather if blowing dust reduces the visibility to below 5/8 statute mile. Taiwan is located in the east coast of mainland China. It is the mean position of the East- Asia major trough. Therefore, during the period of early spring, when a cold high moves out from the arable areas of Mainland China following a propagating trough dust filled air would be affected an extensive area of Taiwan. The falling yellow dust is not only increase the PM10 and PM2.5 but also affects the health of the local residents. In order to make a complete investigation of such condition the EPA supports a number of projects including this one. In this project a data bank of duststorm/sandstorm events is designed and constructed. Data of each case in the recent years are collected and put in the bank. Then, according to those data weather map patterns are classified. In the last part of this work the intensity of the dust event are categorized. Although this work is preliminary it is a very fundamental base of further study.

duststorm/sandstorm, data bank, cold high