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热带气旋路径模糊概率预报的第一步改进方案 总被引:2,自引:0,他引:2
1995年省局“热带气旋路径模糊概率预报方法”课题(简称V1-0)经过了两年的研究和试验,获得较大进展,受到预报员和“全国台风科学研讨会”专家好评。然而,方法虽然在总体上取得较大成功,但其中对某些台风预报误差仍较大,有相当比例是在热带气旋结构特别复杂时出现。改进的热带气旋路径模糊概率预报方法(简称V2-1)针对前方法的薄弱环节进行优化,把目前最前沿的研究成果应用到实际预报中来,使之紧跟90年代台风研究的步伐。1 V1-0简介 V1-0根据南海及其附近区域热带气旋路径左、右折突变与持续稳定的类型… 相似文献
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热带气旋路径预报概率圆应用 总被引:1,自引:2,他引:1
热带气旋路径预报采用预报概率圆可以有效减少不可避免的预报错误,在2004~2007年中央气象台主观路径预报资料的基础上,使用统计方法并根据预报误差与热带气旋预报移动速度和移动方向的相关关系分类,分别计算了相应的24、48、72 h路径预报的70%概率圆半径,修改了原来业务中使用的概率圆半径,以期替代原来在业务中使用的概率圆半径。同时应用修改后的概率圆半径对近5年的路径主观预报进行了分析,给出了2004~2007年预报误差分布特点以及较大预报误差热带气旋个例的误差产生原因,并讨论了该方法改进的可能性。 相似文献
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对多时刻环境因子与热带气旋路径相关的统计分析表明,初始时刻环境场因子对热带气旋路径的预报能力随预报时效的增长而下降;未来时刻环境因子的预报能力高于初始时刻环境场因子;对于一定预报时效的热带气旋路径,具有较高预报能力环境场因子出现时刻大多不与预报时效同时刻;对于48 ̄120小时的预报时效,初始时刻后48-72小时的环境场因子具有较高的预报能力。对NWP产品进行统计释用的热带气旋路径预报模式优于用初如 相似文献
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改进的热带气旋路径模糊概率预报方法试验总结 总被引:1,自引:0,他引:1
用改进的热带气旋路径模糊概率预报方法对1998-2000年进入预报区并达到起报条件的13个热带气旋作了47次预报试验,24h平均误差为116.8km,48h平均误差为281.0km。其中模糊概率大于70%的共有8次,24h平均误差为87.9km,48h平均误差为207.6km,均明显小于总平均误差,达到概率越大误差越小的理想效果。同时试验表明方法对路径发生明显转折的热带气旋有较好的预报能力。 相似文献
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通过对逐步逼近法1995年试验情况与国内外预报台的综合预报以及与国内一些客观预报方法的比较分析,总结出该方法对移动路径明显转折的热带气旋有较好的预报能力,48小时平均误差达到300km以内,特别是当热带气旋的移速发生明显变化时,该方法较之其它客观方法有明显的优越性。 相似文献
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2007年西北太平洋热带气旋定位和预报精度评定 总被引:5,自引:2,他引:3
依据<台风业务和服务规定>分析2007年TC业务定位和业务预报精度,结果表明:各方法的平均定位误差均小于25km,强度预报的24小时和48小时近中心最大风速平均误差为3~7m·s-1和5~11m·s-1,均与往年相当;综合预报的24小时和48小时路径平均距离误差分别为129.8km和215.0km.虽然路径数值预报的能力仍然不能与综合预报相比,但是多模式集成方法相对于综合预报有正技巧,说明这类方法可能成为改善路径预报的途径之一.强度预报的主要参考仍然是统计类预报方法. 相似文献
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热带气旋路径相似预报在目前的业务预报中仍占有很重要的地位,本系统采用各种历史资料及实时资料,结合主要天气系统和500hPa数值预报形势场,选取热气旋路径0小时、24小时、48小时的相似个例,即它不但可以用实况场选取热带气旋的相似过程,而且可以根据数值预报形势场(包括预报热带低压位置)来动态的选取相似过程。 相似文献
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2009年西北太平洋热带气旋定位和业务预报精度评定 总被引:5,自引:2,他引:3
依据《台风业务和服务规定》分析2009年热带气旋(TC)业务定位和业务预报精度,主要包括:6个方法的定位精度,12个综合预报方法、3个客观预报方法和6个数值预报方法的路径预报精度,以及4个方法的强度(近中心最大风速,下同)预报精度评定。结果表明:各方法的平均定位误差均小于21 km,平均17.1 km,较2008年有所改进。国内综合预报方法的24小时、48小时和72小时路径预报的平均距离误差分别为115.8 km、217.5 km和357.1 km,与2008年相比有所偏大;客观预报方法略优于综合预报方法,24小时和48小时预报的平均距离误差分别为113.0 km和211.4 km;4个官方综合预报方法比较发现,中央气象台对我国近海海域的TC路径预报具有明显优势。强度预报仍然以统计方法为主,2009年24小时和48小时近中心最大风速预报的平均误差分别为4.90 m·s~(-1)和7.43 m·s~(-1),相比近10年的平均水平,预报性能没有明显提高。 相似文献
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FUZZY PROBABILITY PREDICTION METHOD FOR TROPICAL CYCLONE TRACK 总被引:2,自引:0,他引:2
Based on forecasting criteria of tropical cyclone categories of left and right turning and stable track and fuzzy mathematical principles, a fuzzy probability prediction method is formulated for track changes. It is 48-h valid for forecasting sudden change or stable track as well as giving fuzzy probability of trajectory, for the use in decision-making. As shown in operational experiments, if is easy to operate, simple to illustrate, objective to quantify.definite to conclude. and satisfactory to actualize. It is dependable with high level of reference, especially when the fuzzy probability is greater than 70%. for errors in direction and 48-h mean distance errors are all lower than those at major forecasting centers at home or abroad. 相似文献
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2002年西北太平洋和南海热带气旋路径主客观预报评价 总被引:3,自引:2,他引:1
利用目前中央气象台热带气旋路径实时业务预报中使用的各种主客观预报产品资料,对2002年西北太平洋和南海热带气旋路径实时业务预报中的主客观预报进行对比分析检验。结果显示:虽然在整体上主观预报要优于客观模式的结果,但客观模式的预报能力已接近主观预报,有时甚至还好于主观预报,特别是48小时以上时效的客观模式较主观预报具有一定的优势;而在客观模式中,全球模式优于台风模式;热带气旋路径数值模式产品的使用对提高热带气旋路径业务预报水平具有十分重要的作用。 相似文献
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给出了一个嵌套于欧洲中期天气预报中心全球谱模式中的套网格模式,用于预报热带气旋路径趋势,提出了一种以欧洲中期天气预报中心提供的时距为24小时的预报场为基础的“接力预报”方法;设计了五种不同的“接力预报”方案;并对8507号和8509号两个热带气旋就各种不同预报方案进行了数值预报试验。结果表明,本模式对热带气旋路径趋势具有较强的预报能力,对疑难路径也具有一定的预报能力,为开展热带气旋的路径趋势预报提供了一个新的途径。文中还对影响热带气旋路径趋势的一些主要因子结合各预报结果进行了分析,为模式尽早投入业务提供了一定的依据。 相似文献
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A review of progress over the past 50 years in observing and forecasting of tropical cyclones is presented. Tremendous progress has been made in track forecasting in the past 20 years with the improvement in numerical model guidance and the use of consensus forecasting, and this has contributed to a number of warning centers now issuing five-day track forecasts that are as accurate as three-day forecasts of a decade ago. Techniques are now available to specify the track forecast uncertainty for assessing the risk of a tropical cyclone. With the advent of five-day forecasts, a focus on improved understanding of formation has led to two field experiments. A recent advance has been in extended-range (5–30 days) forecasts of tropical cyclone events (formations and tracks) in the western North Pacific from the ECMWF 32-day ensemble predictions. This advance is a contribution to a goal of seamless forecasting from one day to a season for tropical cyclones. Little progress has been made in intensity forecasting, although the Hurricane Forecast Improvement Project in the United States and recent field experiments may offer some future advances. Some advances in forecasting tropical cyclone impacts such as storm surge, surface waves, and precipitation have been achieved. Future opportunities for continued advances are possible such that improved warnings can lead to reductions in losses of lives and minimizing damages from tropical cyclones. 相似文献
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我国台风预报业务的现状及思考 总被引:15,自引:1,他引:14
随着数值预报模式和技术以及综合探测体系的不断进步和完善,自20世纪90年代以来我国台风业务预报取得了长足的进步,特别是台风路径业务预报水平进展显著,目前基本达到国际先进水平。通过对我国及国际台风/飓风业务预报现状的回顾,分析了目前我国台风业务预报中存在的主要问题、业务预报难点和亟待解决的科学问题,同时展望了我国台风业务预报在全球气候变化条件下,以及日益增长的国家防灾减灾需求形势下所面临的挑战,并对我国台风业务预报的未来发展做出了一些粗浅的思考,提出了改进我国台风业务预报的相关建议措施。 相似文献
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Summary From 1994 to 2003, fifty-five tropical cyclones entered the Canadian Hurricane Centre (CHC) Response Zone, or about 42% of
all named Atlantic tropical cyclones in this ten-year period, and 2003 was the fourth consecutive year for a tropical cyclone
to make landfall in Canada. The CHC forecasts all tropical cyclones that enter the CHC Response Zone and assumes the lead
in forecasting once the cyclone enters its area of forecast responsibility. This study acknowledges the challenges of forecasting
such tropical cyclones at extratropical latitudes. If a tropical cyclone has been declared extratropical, global models may
no longer use vortex bogussing to carry the cyclone, and even if it is modeled, large model errors often result. The purpose
of this study is to develop a new version of the Florida State University (FSU) hurricane superensemble with greater skill
in tracking tropical cyclones, especially at extratropical latitudes. This has been achieved from the development of the synthetic
superensemble, which is similar to the operational version of the multi-model superensemble that is used at FSU. The synthetic
superensemble differs in that is has a larger set of member models consisting of regular member models, synthetic versions
of these models, and the operational superensemble and its synthetic version. This synthetic superensemble is being used here
to forecast hurricane tracks from the 2001, 2002, and 2003 hurricane seasons. The track forecasts from this method have generally
less error than those of the member models, the operational superensemble, and the ensemble mean. This study shows that the
synthetic superensemble performs consistently well and would be an asset to operational hurricane track forecasting. 相似文献
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Application of evidence theory to quantify uncertainty in hurricane/typhoon track forecasts 总被引:1,自引:0,他引:1
S. V. Poroseva J. Letschert M. Yousuff Hussaini 《Meteorology and Atmospheric Physics》2007,97(1-4):149-169
Summary In the paper, a new technique to quantify the accuracy of models for weather prediction in forecasting tracks of tropical
cyclones using the available best track database is presented. Also a new approach to quantify and improve the accuracy of
tropical cyclone track forecasts where no best track positions are available is suggested. Both techniques rely on the mathematical
tools of evidence theory, which are customized here for application to total uncertainty in track forecasts. 相似文献