The characteristics and influence of the serious drought event lasting eleven years ( 1922 － 1932) in the Yellow River valley
was analyzed in this paper． The result shows that this serious drought event occurred at least once in two hundred years． It happened in
the relatively warmer period under the background of a century － scale drought，which was characterized by long time，wide area，and
heavy damage． During the period of 1922 － 1932，the natural disasters such as drought，locusts，earthquakes，pestilence intertwined
with the man － made disasters ( banditry and war) ，which led to a terrible calamity in the Yellow River valley，the entironment and agricultural
productivity suffered great devastation，and the people underwent all kinds of hardships．

The structure design, data flow frame, characteristic and founction of themeteorologywarning and commanding service system forLanzhou railway flood preventionwas inrtroduced in this paper. By using network technology, the system provided a highly effective, high quality and prompt service platform for the Lanzhou Railroad Bureau. The system provides the real-timemeteorological data, 72 hours fine prediction, three times line prediction in a day, mid-rangeweather forecast and the flood disaster information as well as jurisdictionalboundary chartalong the route. Moreover, based on statistics ofall flood disaster information provided byLanzhou Railroad Bureau andmeteorological data during the period of2002-2007, the temporal and spatial distribution of flood dasster along the railway route has been obtained, and the flood disaster features under the different type andmagnitude ofprecipitationwas also obtained and five gradeswarning ranks have been established, the railway line flood disasterwarning signal is issued for 15 routes, respectively.

The extreme drought eventoccurred in Sichuan and Chongqing region during the period of1935-1937 was analyzed. Itwas an extreme drought event thatmeet in one hundred years in warmer climate period, itpersisted long time and disserved severely, and people’s life and wealth suffered bigness harm. The low ability ofdefence droughtdisaster resulted in seriouse calamity. People in Sichuan and Chongqing regionmust strengthen defence drought and reduction disasterwork under the back ground ofglobal climatewarming.

The research p rogresses ofmetadata and metadata standard at home and meteorological departments were analyzed, and the main p roblems in meteorological data managing and sharing system at p resentwere discussed, and some p rospects ofmetadata requirementwere put forward.