有限区域细网格模式产品在江汉平原暴雨预报中的应用

利用湖北省提供的有限区域细网格模式数值预报产品及降水实况资料，用逐步回归法拟合出江汉平原等区域暴雨方程。方程的拟合效果比较理想，此方程尚有待台站业务考核及改进。     

我国夏半年降水距平与北太平洋海温异常的奇异值分解法分析

利用奇异值分解法分析了我国夏半年各月降水距平与北太平洋海温异常的相互关系，指出：（１）平均意义上，秋冬季海温与我国春末至盛夏各月降水存在显著相互关系；（２）秋冬季赤道东太平洋海温对次年４－５月江南东部和７月高原东侧，黄河中下游地区的降水有显著的影响；（３）盛夏至冬季的赤道中东太平洋海温与前一年６月黄淮地区及７月长江流域降水关系密切。     

石家庄城市供水与气象条件

利用多元回归等统计方法逐月分析了气温、湿度、降水及风等气象因子与供水之间的关系 ,并对闷热指数、焚风等与供水量之间的相互关系和规律进行了分析 ,制作了短期供水预报。     

Interannual and decadal variations of snow cover over Qinghai-Xizang Plateau and their relationships to summer monsoon rainfall in China

Interannual and decadal variations of winter snow cover over the Qinghai-Xizang Plateau (QXP) are analyzed by using monthly mean snow depth data set of 60 stations over QXP for the period of 1958 through 1992. It is found that the winter snow cover over QXP bears a pronounced quasi-biennial oscillation, and it underwent an obvious decadal transition from a poor snow cover period to a rich snow cover period in the late 1970’s during the last 40 years.It is shown that the summer rainfall in the eastern China is closely associated with the winter snow cover over QXP not only in the interannual variation but also in the decadal variation. A clear relationship exists in the quasi-biennial oscillation between the summer rainfall in the northern part of North China and the southern China and the winter snow cover over QXP. Furthermore, the summer rainfall in the four climate divisions of Qinling-Daba Mountains, the Yangtze-Huaihe River Plain, the upper and lower reaches of the Yangtze River showed a remarkable transition from drought period to rainy period in the end of 1970’s, in good correspondence with the decadal transition of the winter snow cover over QXP.     

6月份格陵兰海冰异常对黄河中上游7月份旱涝的影响

通过北极4个区的海水DQ%指数和全国160站7月份降水关系的诊断分析指出,6月份格陵兰海冰异常与黄河中上游7月份旱涝存在着明显的联系,6月份格陵兰海冰少(多)时,黄河中上游7月份易涝（旱）。产生这种联系的物理机制是6月份格陵兰海冰异常影响7月份欧亚大气环流,导致黄河中上游7月份降水产生异常。通过对相关场进行显著性检验,确认了6月份格陵兰海冰异常与黄河中上游7月份旱涝联系在统计上的可靠性。同时发现,有时随机数序列与气象要素场的相关场会达到很高的显著水平,而且这种相关场中的显著相关区的分布并不是杂乱无章的,而是成片分布的。这项工作指出了把对相关场的显著性检验与相关场成因的物理机制分析相结合的必要性。     

用CEOF分析近百年中国东部旱涝的分布及其年际变化特征

通过1850～1991年旱涝百分率的CEOF分析，研究了近百年来中国东部旱涝的分布特征、时空变化特点及年际演变规律。结果表明，我国东部主要有三种旱涝分布类型。第一种类型是以长江流域为中心全国大范围旱或涝，空间位相近似相同，且有10.7年和3.1年周期性变化，振幅强度在1923～1924年间曾发生过增强突变。第二种类型为南北旱涝趋势相反的分布，空间位相自北向南变化显著，且有4.3年周期性变化，振幅强度在1884～1885年间曾有一次减弱突变。第三种类型呈江淮流域与华北和华南旱涝趋势相反的分布，空间位相从南北两个方向向中间或相反方向移动，并有3.4年周期性变化，振幅强度在1911～1912年有过增强突变。     

广西冬寒日数的气候变化特征及其与500hpa高度场的关系

在统计广西86个气象站历年冬寒日数的基础上,分析了平均冬寒日数、最多和最少冬寒日数的地区分布.用聚类分析方法,初步将广西冬寒日数划分为北部、南部、左右江河谷和沿海4个区.对广西8大站冬寒日数的气候变化特征及其与500hPa位势高度场的关系进行了分析,并用逐步回归方法建立了预测模型.     

黑龙江气候变暖的时空变化特征

进入80年代以来，黑龙江气温明显变暖，近120年来年平均气温上升1.4℃，春季次之，气温突变在1990年前后，从年、各季平均气温变化趋势与全国北半球及全球气温变化进行比较，年及冬季我国增暖中心在黑龙江，春季增暖中心在内蒙古北部及黑龙江省；夏秋增暖不明显，但仍有上升趋势，近50年来，50～70年代黑龙江省及全国各大区域普遍增暖不明显，80年代开始黑龙江省增暖明显，三北地区次之，90年代黑龙江增暖更加明显，而全国及其他区域上升已达到80年代北方增温幅度，这里从黑龙江变暖的事实，突变时间，与全球、北半球、全国区域的气温及雪盖海温变化关系来揭示黑龙江气候变化的时空特点。     

基于模糊自整定PID的直升机飞行控制律设计

在经典PID控制律基础上,引入模糊控制的概念设计模糊自整定PID控制律改进无人直升机姿态回路控制器,实现了PID控制器的参数在线自整定,并改善了控制器性能.通过Matlab对闭环系统进行算法仿真,表明模糊自整定PID控制器能够发挥优于传统PID控制器的控制性能.最后对所设计的控制器进行半物理仿真验证,通过对比典型输入指令下经典PID和模糊自整定PID两种控制器的控制效果,验证了模糊自整定PID对系统性能的优化.     

Study of Distinctive Regional Features of Surface Solar Radiation in North and East China

Solar radiation is an important energy source for plants on the earth and also a major component of the global energy balance.Variations in solar radiation incident at the earth's surface profoundly affect the human and terrestrial environment,including the climate change.To provide useful information for predicting the future climate change in China,distinctive regional features in spatial and temporal variations of the surface solar radiation (SSR) and corresponding attributions (such as cloud and aerosol) are analyzed based on SSR observations and other meteorological measurements in North and East China from 1961 to 2007.Multiple models,such as the plane-parallel radiative transfer model,empirical and statistical models,and corrclation and regrcssion analysis methods are used in the study.The results are given as follows.(1) During 1961-2007,the total SSR in North China went through a process from quickly “dimming” to slowly “dimming”,while in East China,a significant transition from “dimming” to “brightening” occurred.Although there are some differences between thc two regional variation trends,long-term variations in SSR in the two regions are basically consistent with the observation worldwide.(2) Between the 1960s and 1980s,in both North and East China,aerosols played a critical rolc in the radiation dimming.However,after 1989,different variation trends of SSR occurred in North and East China,indicating that aerosols were not the dominant factor.(3) Cloud cover contributed less to the variation of SSR in North China,but was thc major attribution in East China and played a promoting role in the reversal of SSR from dimming to brightening,especially in the “remarkable brightening” period,with its contribution as high as 70％.