Risk Analysis of Severe Group Dust-storms in the Eastern Part of Northwest China

The dust storm study is complex and uncertain.the precise dynamic equationsfor dust stormsare not well established,but using risk analysis method,it is certainto enrich the understanding of them.In this paper,a risk estimationmodel was established for severe dust storm based on histogram approach,which provided a newway for dust storms research.Using the historical dust storms data from 1954-2001,the risk values of the occurrence of severe group dust-storms in eastern part of Northwest China were calculated.The resultsshowed that the risk value is 0.8541 every year.The probability of eight or greater than eight times of dust storms is very little,and there are two occurrences in this area by average in a year.Theywould be significant in supplyinguseful quantitativeinformation for decision analysis to recognize and prevent severe dust storms.