Dynamical And Thermal Characteristics Of Dust Storm Relative To Mongolia Cyclone

In this dissertation, the genesis and development of Mongolia cyclone related to a severe dust storm, which occurred during 5-9 April, 2002 in the area of north-east china, north china and Mongolia and the cause of severe dust storm are diagnostically analyzed and simulated respectively. In the first part, we analyze circulation background of the Mongolia cyclone, and then simulate it with the integrated dust numerical prediction system, furthermore we discuss the effect of terrain condition, ambient fields, the property of underlying surface on the genesis and development of Mongolia cyclone and the intensity of dust-storm, finally, we compared it with blowing dust on 13-15 April, 2003 resulted from Mongolia cyclone, getting some conclusions as follows:(1) The development of the cyclone commences in baroclinicity region at the occurrence of the cyclone, the main contribution to the intensification of cyclone comes from the thermal advection, it is must not be overlook the function of the atmospheric baroclinicity. This dust weather case was mainly caused by cyclone cold front and surface high wind behind the cold front. The formation of the surface strong wind is caused by the cyclogenesis, clod advection behind the cold front and the downwardly transmission of the upper level jet momentum.(2) The experiment of reducing the height of the terrain shows that the terrain has a notable influence on the orientation and intensity of the Mongolia cyclone, because the reducing of the height would lead the more North of cyclone, the weaker of the low jet, at last resulting in the weaker of dust storm;the upper level and low level jet decreases by reducing the upper level wind field, the more slowly and weaker of the development of cyclone, and thinness of dust storm;increasing the low level temperature viz weaking the intensity of cold air, improving the development of cyclone;expanding the containing water of soil to boost up the speed of critical friction, at the same time, weak the amount of instantaneous blowing sand and the concentration of dust storm.(3) The results of comparative analyse of different intensive dust stormresulting from Mongolia cyclone show that the same influence system may cause the different intensive dust, because it is not direct ratio for the intendity of dust weather, because of the different cold air, the upper level circulation, and the moving road of Mongolia cyclone causing different dust storm.