Research On The Characteristics And Sand Mechanism Of Dust Strom In Northern China

Dust storm is a disastrous weather phenomenon which has great destructive power and had brought enormous economic losses toward society and environment. As a meteorological disasters and environmental problems, dust storm has attracted a lot of attention of scientists and authorities around the world. With the research on dust storm keep going on, the spatial and temporal distribution of dust weather, dust source ground and the transmission path, diurnal variation of dust weather and sand mechanism had been analyzed clearly. Based on the above study, dust weather warning and prevention measures have also made great progress in China. Research on the revolution of dust storm weather and sand storm mechanism in northern China can not only help us to understand the historical evolution of the dusty weather, changing trend and sand mechanism deeply, but also can help policy maker to develop reasonable and effective mitigation and prevention measures on dust storm.In this study, the history of dust storm of China and dust weather conditions of Xinjiang, Gansu, Inner Mongolia, Ningxia, Shaanxi, Liaoning from January to May in 2014 were analyzed. In addition, the relationship between wind speed and TSP concentration during typical dust storm events in Urumqi, Hami, Dunhuang, Minqin, Hohhot and Cosby were analyzed which aim to found the sand-blowing characteristics and sand-blowing wind speed in different sand sources.The results showed that:(1) The revolution of dust storm from 2000 to 2014 in China was very complex and showing a decreasing trend. In the period of 2000 to 2010, Dust storms happened frequently, while it showed a decreasing trend since 2010, It means that dust storm control measures had played great role in the prevention of dust storm.(2) Analysis on the readings from dust storm monitoring stations in northern China shown that Hami, Kashi, Akesu in southern Xingjiang and Dunhuang and Minqing city in Gansu province were the places where dust storm hit most frequently from January to May in 2014, and April was the month that dust storm broken out in many cities of China, followed by March and May.(3) In the dust weather process, the correlation of wind speed and TSP concentration had a close relationship with dust source area, dust storm influenced area and dust strengthening source areas. When suffered from dust weather happened in dust sourcearea, wind speed had a high correlation with TSP concentration no matter in sand-blowing period or in sand disappearing stage, while the correlation were relatively good and poor when dust weather happened in dust storm influenced area and dust strengthening source areas, respectively.(4) In the process of dust weather, wind speed was not only factor which decided the concentration of TSP and high wind speed did not always brought high concentration of TSP. The concentration of TSP was affected by underlying surface conditions, temperature, humidity, air pressure and diffusion conditions.(5) The relationship of wind speed and TSP concentration in different dust storm process were determined by earth surface conditions, wind speed, temperature, humidity, air pressures in differet areas. the relationship function of wind speed and TSP concentration in northern China was y = 0.42 e0。44 x.