地质灾害与降雨雨型的关系研究

地质灾害的发生与降雨历时、降雨量及降雨雨型有密切的关系,不同雨型的降雨诱发地质灾害的诱发机制具有明显的差异性。本文通过收集的降雨实况与地质灾害反馈资料,将诱发地质灾害的降雨雨型分为3种类型:台风降雨、持续强降雨和局地暴雨。研究表明,台风降雨型降雨诱发地质灾害具有即雨即滑的特点,即地质灾害的发生与降雨在时间上具有较好的对应关系;地质灾害发生空间位置与台风运移轨迹也基本一致。多为群发型地质灾害,灾害规模较小,一般为表层或浅层滑坡、崩塌。持续强降雨型降雨诱发地质灾害,在强降雨过程中地质灾害具有同步发生的特点;在降雨强度不大但连续降雨过程中,地质灾害具有一定的滞后效应;在地质灾害大规模发生后,诱发新的地质灾害雨量阈值提高。局地暴雨型降雨诱发的地质灾害往往集中发生在出现局地暴雨的当日当地。     

广东的洪涝及其对农业的危害与防御对策

对广东省的洪涝灾害进行了分类，主要从气候的角度揭示洪涝的成因，及其对农业生产的危害。广东的洪涝按水分过多的程度，可分为洪水、涝害和湿害；按季节划发，洪涝分成春季洪涝、春夏洪涝、夏秋洪涝和连阴雨等几种类型。洪涝与湿害的气候指标常用年或某的降雨异常来描述。洪涝和湿害的农业气象指标用水分平均旱涝指标来表示。洪涝灾害的形成与季风活动密切有关。地形对洪涝影响明显，洪涝对农业的危害主要有物理性破坏、生理性损伤、生态性危害。防御洪涝的对策主要有加强防灾减灾的组织管理，改善生态环境，提高天气预报准确率等措施。     

全液压深孔钻机适用的钻探参数监测系统

针对全液压深孔钻机的特点,研制了一种钻探参数监测系统（简称钻参仪）。该钻参仪采用模块化设计,可实现钻探参数实时监测、存储、回看、工况识别和数据远近程无线传输等功能。现场试验表明,该钻参仪技术先进,性能稳定可靠,可满足施工需要,效果显著。     

黄河尾闾段一维耦合水沙数学模型研究及其应用

小浪底水库于1999年运用以后,该河道经历了长时间持续冲刷过程.为掌握小浪底水库运用后黄河尾闾段洪水演进特点及河床冲淤规律,采用一维水沙数学模型研究是一条重要的途径.本研究首先采用浑水控制方程,建立了一维耦合水沙数学模型,并利用2003年利津-西河口段汛期实测水沙及汛前断面地形资料对该模型进行率定,计算的流量、水位及含沙量等过程与实测值吻合较好;然后采用2015年利津—汊3段汛期实测资料对该模型进行验证,结果显示水位与冲淤量计算值与实测值较为符合;最后基于2015年实测洪水过程,计算了若干组不同断面间距下的洪水演进及冲淤过程,分析了不同断面间距对沿程水位及河段冲淤量等计算结果的影响,结果表明:采用不同断面间距对水位计算结果影响较小,而对冲淤量计算结果会产生一定影响;在河段水沙及冲淤特性复杂的情况下,采用一维数学水沙模型计算时应考虑断面间距的选择.     

Seismic comprehensive forecast based on modified project pursuit regression

In the research of projection pursuit for seismic comprehensive forecast, the algorithm of projection pursuit regression (PPR) is one of most applicable methods. But generally, the algorithm structure of the PPR is very complicated. By partial smooth regressions for many times, it has a large amount of calculation and complicated extrapolation, so it is easily trapped in partial solution. On the basis of the algorithm features of the PPR method, some solutions are given as below to aim at some shortcomings in the PPR calculation: to optimize project direction by using particle swarm optimization instead of Gauss-Newton algorithm, to simplify the optimal process with fitting ridge function by using Hermitian polynomial instead of piecewise linear regression. The overall optimal ridge function can be obtained without grouping the parameter optimization. The modeling capability and calculating accuracy of projection pursuit method are tested by means of numerical emulation technique on the basis of particle swarm optimization and Hermitian polynomial, and then applied to the seismic comprehensive forecasting models of poly-dimensional seismic time series and general disorder seismic samples. The calculation and analysis show that the projection pursuit model in this paper is characterized by simplicity, celerity and effectiveness. And this model is approved to have satisfactory effects in the real seismic comprehensive forecasting, which can be regarded as a comprehensive analysis method in seismic comprehensive forecast.     

针对模式风场的格点预报订正方案对比

为了将格点观测融合产品用于模式预报产品的滚动订正中,获得精准的预报效果,使用国家气象信息中心HRCLDAS（High Resolution China Meteorological Administration Land Data Assimilation System）业务系统产生的高频次格点风场融合产品作为实况资料,采用两种风场模型和8种格点误差订正方案,对模式风预报产品进行订正预报试验,试验选择欧洲中期天气预报中心10 m风预报产品的2017年1月1日—2月28日以及2017年6月1日—7月31日两个时间段,进行了预报模拟试验,对8种格点误差订正方案的订正结果进行检验,同时将订正场插值到站点,使用国家级2400个地面气象站风场资料进行站点检验,结果表明:无论从格点还是站点检验的平均绝对偏差、准确率、绝对偏差分布频率结果看,采用基于模式和实况因子的全格点滑动建模订正方案具有最佳的订正效果。     

集合数值预报方法在山洪预报中的初步应用

选取湖南4个典型山洪个例,分析了嵌套模式不同分辨率的预报效果,并采用多物理过程组合的集合预报方法,研究区域集合数值预报技术在山洪预报中的应用。研究指出,单一模式条件下,使用模式嵌套技术提高分辨率,并不能有效地改进对引发山洪灾害的突发强降水过程的预报能力,且这种单一的确定性预报,对暴雨等灾害性天气的预报存在不确定性。集合预报是解决单一预报不确定性提出的新方法,与单一模式提供的确定性预报结果相比,集合预报可为山洪预报提供多种定量预报产品。利用集合平均预报、极值预报,可以引导对山洪采取分类应对措施;集合预报在给出降水分布的同时,还给出伴随预报结果的可信度;概率定量降水预报(PQPF)与水文预报模型结合,可以用于概率水文预报。     

全国水文预报技术竞赛参赛流域水文模型分析

对全国首次水文预报技术竞赛中参赛的10个流域水文模型的结构及模拟技术,分别从各个主要环节进行分类与综述;并根据技术竞赛检验结果所揭示的现象,就参赛水文模型的模拟及应用进行了分析与讨论。     

The Meta-Gaussian Bayesian Processor of Forecasts and Associated Preliminary Experiments

Public weather services are trending toward providing users with probabilistic weather forecasts, in place of traditional deterministic forecasts. Probabilistic forecasting techniques are continually being improved to optimize available forecasting information. The Bayesian Processor of Forecast (BPF), a new statistical method for probabilistic forecast, can transform a deterministic forecast into a probabilistic forecast according to the historical statistical relationship between observations and forecasts generated by that forecasting system. This technique accounts for the typical forecasting performance of a deterministic forecasting system in quantifying the forecast uncertainty. The meta-Gaussian likelihood model is suitable for a variety of stochastic dependence structures with monotone likelihood ratios. The meta-Gaussian BPF adopting this kind of likelihood model can therefore be applied across many fields, including meteorology and hydrology. The Bayes theorem with two continuous random variables and the normal-linear BPF are briefly introduced. The meta-Gaussian BPF for a continuous predictand using a single predictor is then presented and discussed. The performance of the meta-Gaussian BPF is tested in a preliminary experiment. Control forecasts of daily surface temperature at 0000 UTC at Changsha and Wuhan stations are used as the deterministic forecast data. These control forecasts are taken from ensemble predictions with a 96-h lead time generated by the National Meteorological Center of the China Meteorological Administration, the European Centre for Medium-Range Weather Forecasts, and the US National Centers for Environmental Prediction during January 2008. The results of the experiment show that the meta-Gaussian BPF can transform a deterministic control forecast of surface temperature from any one of the three ensemble predictions into a useful probabilistic forecast of surface temperature. These probabilistic forecasts quantify the uncertainty of the control forecast; accordingly, the performance of the probabilistic forecasts differs based on the source of the underlying deterministic control forecasts.     

哈密地区南部一次大降水机制分析

对造成哈密南部"2000·6·23"大降水的主要影响系统南疆低槽、北方冷空气、中低层切变等进行了描述,并从热力因素、动力因素两方面对其特征予以剖析,得到哈密南部大降水预报的某些着眼点.