阿坝州短期森林火险等级划分及预报

在分析阿坝州冬春季防火期气象条件的基础上,确定了日森林火险等级,运用T213数值预报产品,建立森林火险预报方法.     

井冈山森林火险等级划分及预报模型构建

森林火灾严重威胁生态安全和国民经济,由于不同林地的气候以及可燃物存在差异,森林火险具有明显的区域性特征。因此,在考虑气象因子的基础上,将可燃物含水率引入小区域的森林火险指数的计算,对建立更精确的小区域森林火险等级标准和预报模型具有重要意义。本研究系统地分析了2013—2016年井冈山地区森林可燃物含水率与气象因子的分布频率及因子间的相互关系。通过主成分分析方法对所有因子进行降维处理,获得火险因子得分方程,并计算出2013—2016年井冈山地区逐日森林火险指数,进而构建火险等级划分和森林火险等级预报模型。结果表明:井冈山森林火险等级划分为5类,分别为低(火险值≤0.024)、较低(0.024火险值≤0.067)、高(0.067火险值≤0.167)、较高(0.167火险值≤0.232)、极高(火险值0.232)。基于BP神经网络模型构建了井冈山森林火险等级预报模型,预测精度可达96.4%。并利用2013—2017年卫星监测到的井冈山地区热源点数据对模型进行检验,预报准确率高达92.3%,表明该火险等级标准和预报模型能够满足井冈山地区日常防火业务需求。     

东营市森林火险天气等级预报系统

利用9210传输的气象资料，选用国家气象中心T106和HLAFS数值预报产品中的要素作为火险天气因子，根据森林火险原因，建立了东营市森林火险天气等级预报系统。     

贵州森林火险的气象条件及等级趋势预报

分析了贵州省发生森林火险的气象条件、森林火险的时空分布及主要影响天气系统，对2002年的森林火灾作出了趋势预报。     

山西运城市森林火险等级预报系统

利用有关气象及森林火灾资料，分析了林林火灾的发生与气象条件、火条件及森林含水率的关系，计算了森林火险综合预报指标，建立了以预报方程，经试用效果良好。     

东营市森林火险天气等级预报系统

利用9210传输的气象资料,选用国家气象中心T106和HLAFS数值预报产品中的要素作为火险天气因子,根据森林火险原理,建立了东营市森林火险天气等级预报系统.     

重庆市森林火险等级预报方法

根据重庆林火发生特点及林火与气象条件的关系，划分森林火险等级，并引入ＥＣＭＷＦ数值预报产品建立森林火险等级预测方法，试验效果良好。     

焦作市森林火险等级预报系统

利用1989～1999年焦作市逐日森林火险天气等级资料，分析了焦作地区森林火险与气象要素的关系，建立了焦作市火险等级预报系统。经2001～2002年实际应用，效果良好。     

焦作市森林火险等级预报系统

利用1989～1999年焦作市逐日森林火险天气等级资料,分析了焦作地区森林火险与气象要素的关系,建立了焦作市火险等级预报系统.经2001～2002年实际应用,效果良好.     

准地转Q矢量分析及其在短期天气预报中的应用

本文介绍了准地转Q矢量分析理论和方法,给出用Q矢量散度表示强迫项的准地转ω方程和Q矢量的物理意义。 用Q矢量分析方法诊断了1987年8月4日在辽宁出现的一次强对流天气过程,并与数值预报结果进行了比较,结果表明,这种方法能够较清楚地揭示强。对流天气过程中大尺度环境场的变化。可以为业务预报提供一些有参考价值的信息。     

Conditions for formation and short-range forecasting of severe squalls

A physical-statistical approach to the severe squall forecasting is considered. It is based on the output data of the regional hydrodynamic model of Hydrometeorological Center of Russia. By using the multi-dimensional discriminant analysis of a chosen set of predictors, a number of relationships are developed for the severe squall prediction; estimates of forecasting efficiency are presented for these relationships on the developmental sample. Physical interpretation of the obtained relationships is given.     

Analysis of lightning-induced forest fires in Austria

Besides human-caused fires, lightning is the major reason for forest fire ignition in Austria. In order to analyse the causes of ignition and to characterise lightning-induced forest fires, fire records were compared with the real appearance of lightning events by using the Austrian Lightning Detection and Information System for the period from 1993 to 2010. A probability was estimated for each forest fire being caused by lightning by using a decision tree and decision matrices based on flash characteristics (e.g. amplitude, time, location). It could be shown that 15 % of documented forest fires were lightning-caused. Nearly all lightning-caused fires were found during the summer months, whereas almost 40 % of all fires occurring from June to August were naturally caused. Most lightning-caused fires took place in the south and east of Austria. Lightning fires were more frequent at higher altitudes and primarily affected conifer forests. The median burned area was lower than that for anthropogenic forest fires.     

Operative short-range hydrodynamic weather forecasting at the points and its efficiency

Efficiency is discussed of operative hydrodynamic forecasts of meteorological quantities and weather characteristics at the points. Efficiency of hydrodynamic forecasts exceeds that of synoptic forecasts. This allows introducing detailed operative hydrodynamic forecasting of weather at the points.     

基于关系数据库的短期气候预测业务系统

介绍了四川省气象台短期气候预测业务系统的设计思路及构成该系统的各模块的功能和程序实现.     

基于关系数据库的短期气候预测业务系统

介绍了四川省气象台短期气候预测业务系统的设计思路及构成该系统的各模块的功能和程序实现。     

南充市短期预报决策支持系统概述

本文介绍了南充市短期预报决策支持系统(简称DDS)的主要设计思路,这是南充市气象局近年来在传统预报方法改造和新一轮客观预报方法研究过程中所做的一部分工作,希望能为客观预报方法研发活动提供一点参考.     

南充市短期预报决策支持系统概述

本文介绍了南充市短期预报决策支持系统(简称DDS)的主要设计思路．这是南充市气象局近年来在传统预报方法改造和新一轮客观预报方法研究过程中所做的一部分工作．希望能为客观预报方法研发活动提供一点参考。     

An investigation of the tipping term as a prognostic tool in short-range thunderstorm forecasting

A nowcasting system, GANDOLF, was operated by the Met Office and the University of Salford during the Sydney 2000 Forecast Demonstration Project (FDP). The purpose of this project was to test and evaluate the current state-of-the-art in nowcasting technology, and initial verification by the University of Salford has shown GANDOLF's performance to be poor. The system uses a conceptual model of the life cycle of an idealised convective cell to forecast the evolution of radar-observed storms in an object-oriented fashion. Analysis has shown the implementation of the model to be inadequate due in part to its reliance on relatively low resolution NWP model forecasts rather than the use of conceptual modelling itself. The advent of very high resolution three dimensional wind fields produced by four dimensional variational analysis (4DVAR) modelling techniques offers a way of circumventing many of the problems inherent in GANDOLF, and such data have been obtained for the cases during which GANDOLF was operational. These were produced by the National Center for Atmospheric Research's VDRAS system, which was also operated during the FDP, as part of the three-dimensional US Autonowcast system. The wind data allowed the calculation of time series of the three-dimensional tipping term field, which, it is suggested, can be used as a prognostic tool in automated convection nowcasting. This paper summarises the theoretical background of the tipping term in the context of severe storms, and presents the results of a number of tests performed on the data. The conclusions of these tests indicate that the tipping term may be a useful prognostic tool. Observations of the increasing asymmetry in the tipping term couplet predicted by theory as convection reaches its maximum intensity may offer a way of improving objective analysis of the life cycle of cells.