Abstract:The paleoclimatic studies of reconstructions on the Little Ice Age climate with proxy data and records of meteorology in history are reviewed. The global and East Asian monsoon regions′ climatic features and the possible factors of inducing low temperatures during the Little Ice Age are conclued. It is also introduced that the present numerical simulating results on mechanisms of the Little Ice Age, and it is suggested that the main effective factors and some feedback processes should be put into models for simulating in the future.

Abstract:By using the routine sounding and surface observation data, the circulation features and physical causes for the heavy rain event occurred in the East Side of Qinghai-Tibet Plateau on 8-9 June, 2002 are diagnosed. Furthermore, based on MM4 model output,a mesoscale analysis is made according to moist potential vorticity. The results show that the spatial and temporal variations of moist potential vorticity can give good indication of the development of mesoscale cyclone and heavy rain. The heavy rain is located between the positive and negative moist potential vorticity zones in the lower troposphere, the rapid development of mesoscale cyclone is closely related with the spread downward of disorder moist potential vorticity in the higher troposphere.

Abstract:Based on the area rainfall data in the upper reaches of Three Gorges (including five valley:Wujiang, Chongqing-Wanxian, Wanxian-baqu, Jialingjiang, Mintuojiang) during 1951-2000, the drought/flooding distribution characteristics and its cause in May, June, July, August and summer in the Yangtze Gorges are analyzed. The impact of some main circulation systems on the area is studied, and the prediction models of various basins area rainfall are established respectively. The model predictions are successful during the years of 2000, 2001, 2002.

Abstract:The structure and main functions of the near-real time processing system of meteorological radiation data are described respectively. The service tool of the system design and the situation of system operation are introduced. The method and features of data quality control are also introduced in detail.

Abstract:The methods to calculate the river valley area rainfalls, such as Thiessen polygon method and successive correction method are introduced, and actual area rainfalls of five small valley areas in Hunan in 1998(May-Sep.),1999(May-Sep.) and 2000(May-Aug.) are respectively computed by these methods and arithmetical average method.As a whole, there is not notable difference,but there is a great diversity of area rainfalls day by day using different methods.

Abstract:With the need in the new forecasting operation process,by virtue of the similarity between the HLAFS products in MICAPS platform and the three-dimensional space physics field relative to the initial,development and extinction of the heavy rain,a prediction of the on/off region heavy rain is made under complex examination and analysis which is based on the magnitude interpretation and application. The programming, automation and objectivity are realized in the whole process. Based on the mean field distance of the two types of weather process,the heavy rain prediction with the analog discriminatory analysis results is made. The examing results are reasonable, the mean TS during May-September,1999-2002 is more than 33%.

Abstract:Based on the geographic location data of 66 meteorological stations in Fujian Province, including latitude(Φ), elevation(H), distances(S) from seaside to station, and relative altitude(Δh), an estimation model of annual minimum temperature is developed.

Abstract:Firstly, based on the conventional observations at forty-two meteorological stations in Qinghai Province, initial guesses of maximum and minimum temperature are made with the statistic method and the forecaster′s program. Secondly, the initial ones are objectively modified as combined with numerical forecasting product and real time observations. Finally, the forecast of the maximum and minimum temperature are given. As a result, an objectively forecasting method of the maximum and minimum temperature adapting to Qinghai Province is developed.

Abstract:The strong area rainfall in the six drainage areas of the upper reaches of Changjiang River from 1971 to 2000 is statistically analyzed.Through the relationships of the frequency, extremum distribution, running extremum with the strong precipitation among the six drainage areas, the spatial temporal distribution characteristics are given. It is shown that there is the obvious seasonality, distinct annual variation, obvious differences in heavy area rainfall frequency distribution, ordering distribution, extremum distribution, precipitation intensity among six drainage areas, and close relationships between border drainage areas.

Abstract:During the spring of 2002, totally 12 sand-stormy processes, including 4 severe sand-stormy processes, occurred in China. Using mainly surface synoptic maps, the spatial and temporal distribution characteristics of the sand-stormy weather event are analyzed. Furthermore, factors such as soil situation, dynamic and thermodynamic conditions contributing to the sand-stormy weather are researched.

Abstract:Recent years, BP model has been applied to atmospheric pollution forecast, a neural network prediction model of atmospheric pollutant concentration is set up. The research results show: the absolute errors of TSP between calculating and the monitoring is from 4×10^-3mg·m^-3to 3×10^-2mg·m^-3, the absolute errors of NO_X between the calculating and the monitoring is from 5×10^-3mg·m ^-3 to 2×10^-2mg·m^-3. The correlation between results of calculating and the monitoring is very well. As one of the neural network models, BP model has been applied widely, which is a simple and effective algorithm.So, BP neural network model has supplied a new way for the air pollution forecast.