Abstract:The theme for World Meteorological Days (WMD),2002 is "Reducing vulnerability to weather and climate extremes ". In the light of this theme, the following four problems are in general illustrated: (1) definitions of weather and climate extreme events; (2) changes in weather and climate extremes for the past 100 years on the global basis, and their association with global climate change ;(3) projection of global weather and climate extreme events for this century; and (4) adaptation and mitigation response strategy for reducing vulnerability to weather and climate extreme events. Due to space limitation, studies in this regard made by Chinese scientists have not included.

Abstract:Based on NCEP/NCAR reanalysis data and NOAA OLR data,the features of summer monsoon of 1998 in the eastern China are investigated.Results show that average location of subtropical ridge in 1998 is in the south of secular average position, summer monsoon is stronger with long time strong convection activity in South China and Yangtze River Basins,weak summer monsoon and convection in North China. LFO (low-frequency oscillation) is obvious in Eastern China.

Abstract:The meteorological electric loads, which follow weather conditions, is deduced from the loads of electric network over four provinces in central China according to data from February 1997 to May 2000. The relations between meteorological electric loads and weather data are analysed,and the features and their variation rules of relations between meteorological electric loads and air temperture over four provinces in central China are discussed,respectively. The investigation shows that the correlativity bewteen them is in evidence. The correlative coefficient is positive when average temperture is more than 20℃ and negative when it is below 20℃. And the meteorological electric loads vary rapidly with air temperture when it is among 25-28℃.

Abstract:The climatic characteristics of area precipitation and flood peak in Shuiyang River are analyzed using the water level and precipitation data from 1964 to 1999.The results show that in June,July and August,the average area rainfall are 241.5mm,186.5mm and 155.7mm,respectively.There are 13 and 25 times of over alerting water level in Xuancheng and in Xinhezhuang of Anhui Province,respectively.There is weekly continuous rain days before the flood peak,the weekly area precipitation is 164.5mm.Moreover,the results also show that the area precipitation within a season undergoes 60-day quasi-period,and the water level 60-and 120-day quasi-period in Xinhezhuang.And,by using the wavelet analysis,it is found that the mean daily water level in Xuancheng in 1999 undergoes 60-day quasi-period.It is consistent with that in Xinhezhuang by using the spectral analysis.

Abstract:A operational system of real-time mesoscale numerical weather forecast is developed based on SJ-100 Cluster System of parallel computing. By acquiring the 48 hour forecast of T106 numerical weather simulation and surface and radiosonde observations,including sea surface temperature and local surface observations, the NCAR/PSU MM5 model is running over three nesting domains of 135, 45 and 15 km grid length. The quasi-operational experiment has been conducted since January 2001 with 12 hour FDDA prior to the initial time on a cluster composed by 8 Intel PⅢ-800 CPU. The system displays considerable capability for regional short range weather forecast of precipitation, temperature, wind, moisture at the surface layer. The forecast productions consist of various weather elements and phenomena with quantitative analyses, timing and locations and are displayed in the form of graphics, table and text.

Abstract:The mean annual and season spatial distributions of dust storm, fly sand, floating dust are given by using observations from 1970 to 2000. The reasons of causing the dust weather are analyzed. It is found that there was a dust strip passing from Wuwei via Jingtai and Baiyin and Huining to Tianshui and Huixian, the floating dust weather occurred frequently over there. The dust strip was consistent with the rainless strip from middle to south of Gansu Province, and with the lay of the land of northeast of Qinghai-Xizang Plateau. The dust strip is one of the reasons of desert area extending in middle and south of Gansu.

Abstract:By using symmetry instability criterion,an unusual storm smow appeared on January 6 to 7,2001 in Shandong Province is analysed,the results show that the storm snow occurred in the symmetry instability atmosphere,low-level jet caused warm and humid air converging and ascending in lower troposphere and stimulated the symmetry instability energy releasing and then the event of storm snowfall occurred.The Changjiang-Huaihe cyclone and the region of storm snow moved towards the area of symmetry instability.

Abstract:By using the Doppler radar data including its intensity, velocity and VAD products,a stable rainfall process is analysed.The results provide guidance for nowcasting of the rainfall process in the different stages.

Abstract:"Objective Analysis and Graphic System″ is a two-dimensional plot program with friendly graphic interface, which runs on Microsoft Windows. It has many kinds of data interface, and can plot contour, streamline, vector, geographic maps and so on. The software also can conduct the objective analysis for conventional meteorological observation data and output the analyzed data to the specified directory of PC. Based on the output data files, the user can choose some pressure layer and the various variables to plot the meteorological maps.

Abstract:In order to scan and retrieve historical synaptic charts on computer ,with advanced technique of graphic digitizing,a digitized historical synoptic chart and its retrieval system is developed based on MICAPS.It is important for the meteorological scientific research and weather forecast.

Abstract:According on the law of the wheat scab activities,its life cycle is divided into three periods,they are hypha formation period,winter resting period,and spread period.Meteorological elements for each period are chosen as wheat scab weather indexes,which are used to analysis,evaluate and forecast the wheat scab weather conditions.