Wind Erosion Processes during Dust Storm in Dunhuang, China

In order to clarify the process of dust outbreak and the relationship between ground surface condition, such as surface soil water content, temperature, vegetation cover etc, and dust outbreak, two automatic observation stations have settled in Dunhuang, China where is one of the main regions of dust storm occurring and passing. Analysis the obtained data during March 23 to May 18 shows that wind erosion occurs during dust storms occurring or passing in Dunhuang. These dust storms are probably generated by cold frontal systems with dry squall lines. Dust concentration Index in the air (DCI) increases exponentially with wind speed or friction velocity when strong wind blown (wind speed at 10m is over about 6m/s or friction velocity is over about 0.2m/s). Wind erosion processes can be divided into 4 stages as (1) pre- erosion; (2) outbreak; (3) passing and (4) calming down stages.