The Feature And Affecting Factor For Dust Storm In The South Region Of Mongolia

This research work has studied the condition of dust storm in the arid and semiarid areas of the Mongolian Southern. The research work involved 5 aimags(province) of Mongolia, as well as the dust storm mostly occurs in these aimags, and the dust storm is the main disaster for these aimags.In general, the dust storm is disaster that mostly occurs, and its range is very wide. Although the dust storm is one the natural disasters, for last years, the mining and industrial dust which occurs by the participation has been raised. Thus we must do the researches regarding this field at the higher level.For Mongolia, the dust storm has a frequency of month, and the 90 percent of total of the dust storm occurs in spring and autumn seasons. But the 60 percent of this 90 percent occurs in only spring time. For period of time, the research studied the condition of only spring time in the last 10 years(2004-2013).Newish side of the research is that the researches for the dust storm had been began since 1960 s in Mongolia, and the condition of those past years was made by the division into periods. For instance: 1960-1980, 1980-1990, 1960-2004 etc. But the access information that was made since 2000 s was lacking, and so making the conditions of the last 10 years is very special. In addition, another special thing is that there hadn’t been any research which had made the conditions of the dust storm with the change of vegetation cover. Thus this is one of the newish works.The research work that was made at the areas of the research consists of main three parts.? The analysis for the climate information of 28 stations at the areas of the research;? The information processing of MODIS/TERRA satellite;? The comparison for above information that was collected;For seeing the research result, the frequency of the dust storm in spring time of 2004-2013 has been increasing. But the year of 2006, 2010 and 2013 had specific dust storm, and the growth for other years was less. That was the overall of three months. For each month, the storm had been increased in March, had been decreased in April, and had been decreased in May.For seeing the wind direction, the southern wind had dominated in these months.Wind and dust storm occur under the influence of many factors. I studied the main factor which provides the dust storm in the southern of Mongolia. For choosing and seeing in detail two stations, I determined that when strong wind occurs, it maybe had been affected the constant wind, areas elevation and cyclogenesis progress.The southern of Mongolia is the region that has less precipitation, more warm and acid sunny day and less vegetation cover. When I defined the NDVI of this region, I calculated the NDVI of each month between from April to October. When I made the comparison of March, April and May, calculated adding March.For seeing the condition of NDVI, the vegetation cover had been less in 2008 and 2009 whereas had been the highest in 2011 and 2012. In general, the NDVI had tended to decrease in 2004-2009 whereas had tended to increase in 2010-2013. When I compared the change and condition of vegetation cover with the number that dust storm occurred, the research showed that the change and condition of vegetation cover hadn’t affected on the source of dust storm.In practice, the vegetation cover and the progress that dust storm occurs are the conditions that have direct relevance. But this situation doesn’t happen at the Gobi and desert region of Mongolia because the arid and dried areas, less soil richness and less plant output have affected for that. We can see that although the plant output has been evolved by the change of precipitation, this change is very less and so the effect on the environment is less. Thus, the condition of vegetation cover couldn’t affect to the source of dust storm.