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1.
The possible changes of tropical cyclone(TC) tracks and their influence on the future basin-wide intensity of TCs over the western North Pacific(WNP) are examined based on the projected large-scale environments derived from a selection of CMIP5(Coupled Model Intercomparison Project Phase 5) models. Specific attention is paid to the performance of the CMIP5 climate models in simulating the large-scale environment for TC development over the WNP. A downscaling system including individual models for simulating the TC track and intensity is used to select the CMIP5 models and to simulate the TC activity in the future.The assessment of the future track and intensity changes of TCs is based on the projected large-scale environment in the21 st century from a selection of nine CMIP5 climate models under the Representative Concentration Pathway 4.5(RCP4.5)scenario. Due to changes in mean steering flows, the influence of TCs over the South China Sea area is projected to decrease,with an increasing number of TCs taking a northwestward track. Changes in prevailing tracks and their contribution to basin-wide intensity change show considerable inter-model variability. The influences of changes in prevailing track make a marked contribution to TC intensity change in some models, tending to counteract the effect of SST warming. This study suggests that attention should be paid to the simulated large-scale environment when assessing the future changes in regional TC activity based on climate models. In addition, the change in prevailing tracks should be considered when assessing future TC intensity change. 相似文献
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基于IBTrACS提供的热带气旋最佳路径数据集,在统计分析历史热带气旋的发生年频次、发生位置、路径移动及强度变化等的基础上,建立了西北太平洋热带气旋轨迹合成模型。模型包括生成模型、移动模型、消亡模型及强度模型4个部分,并从地理轨迹密度、年登陆率、登陆风速分布三个方面,对模拟的气旋路径与历史气旋路径进行比较,以验证模型的准确性和可靠性。结果表明,构建的西北太平洋热带气旋全路径统计模拟模型稳健可靠,可进一步应用于研究区热带气旋的定量精细化的风险评估,能提高气旋风险灾害评估的可信度。 相似文献
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Influences of Tropical Cyclones on China During 1965-2004 总被引：2，自引：0，他引：2
Using the Joint Typhoon Warning Center （JTWC） and China Meteorological Administration （CMA） tropical cyclone track datasets, variations in frequency and intensity of the affecting-China tropical cyclones （ACTCs） are studied for the period of 1965-2004. First, the differences between the two tropical cyclone datasets are examined. The annual frequencies of tropical cyclones in the western North Pacific basin are reasonably consistent to each other, while the intensity records are less reliable. The annual numbers of ACTCs based on different datasets are close to each other with similar interdecadal and interannual variations. However, the maximum intensity and the annual frequency of ACTCs for strong categories show great dependence on datasets. Tropical cyclone impacts on China show the same variations as the annual number of ACTCs and also show dependence on datasets. Differences in tropical cyclone impacts on China are mainly caused by datasets used. The annual frequency of ACTCs, especially the length of lifetime of ones that make landfall, and the intensity estimates all have effects on the value of impacts on China. 相似文献
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近30年影响我国东南沿海的热带气旋降水强度变化特征分析 总被引：3，自引：0，他引：3
利用中国地面台站逐日降水资料和中国气象局上海台风研究所整编的热带气旋最佳路径资料研究了1978～2007年影响我国热带气旋降水强度的变化及其对我国东南沿海盛夏降水变化的影响.近30年影响我国东南沿海盛夏的热带气旋降水增加是导致我国东南沿海盛夏降水显著增加的主要原因.仅从热带气旋降水来看,东南沿海和内陆(包括江西、湖南东部和湖北南部)热带气旋降水强度显著增加,而影响热带气旋降水频次略有增加.通过对雨量站与引起降水热带气旋的中心距离的变化分析发现:内陆地区影响热带气旋距离显著下降,近距离热带气旋引起降水的增加,是该区域热带气旋降水强度增加的主要来源;而东南沿海地区近距离热带气旋降水增加不明显,热带气旋降水强度的增加主要由于同距离热带气旋降水强度的增加.热带气旋经过频次的空间的变化结果证实,近30年经过中国沿海的TC个数变化不大,仅福建沿海一带略有增加,而内陆地区则增加明显,且经过该区域时热带气旋移动速度变慢,这均与该区域近距离热带气旋降水的增加一致. 相似文献
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Matthew Ranson Carolyn Kousky Matthias Ruth Lesley Jantarasami Allison Crimmins Lisa Tarquinio 《Climatic change》2014,127(2):227-241
This paper provides the first quantitative synthesis of the rapidly growing literature on future tropical and extratropical cyclone damages under climate change. We estimate a probability distribution for the predicted impact of changes in global surface air temperatures on future storm damages, using an ensemble of 478 estimates of the temperature-damage relationship from nineteen studies. Our analysis produces three main empirical results. First, we find strong but not conclusive support for the hypothesis that climate change will cause damages from tropical cyclones and wind storms to increase, with most models predicting higher future storm damages due to climate change. Second, there is substantial variation in projected changes in losses across regions. Potential changes in damages are greatest in the North Atlantic basin, where the multi-model average predicts that a 2.5 °C increase in global surface air temperature would cause hurricane damages to increase by 63 %. The ensemble predictions for Western North Pacific tropical cyclones and European wind storms (extratropical cyclones) are +28 % and +23 %, respectively. Finally, our analysis shows that existing models of storm damages under climate change generate a wide range of predictions, ranging from moderate decreases to very large increases in losses. 相似文献
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全球变暖对台风活动影响的研究进展 总被引：14，自引：1，他引：13
全球变暖是当前热点问题之一,各大洋区时有发生的"超乎寻常"的台风活动也广为关注.全球范围内的台风活动特征是否悄然发生了变化?这种变化与全球变暖是否存在关联?这些问题已成为国际台风界的重点研究内容之一,近年来取得了许多进展.文中从全球台风活动特征变化事实的观测研究,成因分析、数值模拟与预测等方面对此进行了概述.综合各方观点,得到主要共识如下:单个台风的异常活动不宜直接归因于气候变化;全球台风频数的年际变化趋势并不明显;沿海地区人口增长和基础设施增加是近期台风对社会影响加重的主要原因;自1970年以来,一些海区的超强台风比例明显增大,比目前数值模式的模拟结果要大许多;如果全球气候持续变暖,台风的最大风速和降水很可能会继续增加;尽管在台风记录中同时有支持和不支持人类活动(全球变暖的影响)信号存在的证据,但在这一点上还不能给出一致的肯定结论.另外,由于台风和相关气候资料存在均一性方面问题,气候数值模式对台风气候特征描述也存在缺陷,这两类问题的存在使得在目前阶段确切阐明全球变暖和台风活动的关系仍有极大的不确定性. 相似文献
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罗亚丽 《气候变化研究进展》2012,8(2):90-98
自1950年以来的观测证据表明,有些极端天气和气候事件已经发生了变化。全球尺度上,人为影响可能已经导致极端日最低和最高温度升高;由于平均海平面上升,人类活动可能已对沿海极端高水位事件的增加产生了影响;具有中等信度的是,人为影响已导致全球强降水增加;由于热带气旋历史记录的不确定性、缺乏对热带气旋与气候变化之间关联的物理机制的完整认识及热带气旋自然变率的程度,将可检测到的热带气旋活动变化归因于人为影响仅具有低信度。将单一的极端事件变化归因于人为气候变化具有挑战性。对极端事件变化预估的信度取决于事件的类型、区域和季节、观测资料的数量和质量、基本物理过程的认知水平及模式对其模拟的可靠性。 相似文献
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以神经网络方法为基础,建立西北太平洋热带气旋强度预测模型,模型首先进行历史相似热带气旋选择。从选择的样本出发,计算得到一组气候持续因子、天气学经验因子和动力学因子, 对这些因子采用逐步回归方法进行筛选,将筛选得到的因子同对应时效的热带气旋强度输入神经网络训练模块,从而得到优化的预测模型。从2004-2005年西北太平洋26个热带气旋过程对12,24,36,48,72h等不同预报时效分别进行的634,582,530,478,426次预测试验结果的统计来看,相对于线性回归模型预测水平,该模型显著降低了各时段的预测误差。从几个热带气旋个例的预测结果来看, 该模型对超强台风, 以及具有强度迅速加强、再次加强等特征的热带气旋过程均有很好的描述能力。 相似文献
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Fine-resolution regional climate simulations of tropical cyclones (TCs) are performed over the eastern Australian region. The horizontal resolution (30 km) is fine enough that a good climatological simulation of observed tropical cyclone formation is obtained using the observed tropical cyclone lower wind speed threshold (17 m s–1). This simulation is performed without the insertion of artificial vortices (bogussing). The simulated occurrence of cyclones, measured in numbers of days of cyclone activity, is slightly greater than observed. While the model-simulated distribution of central pressures resembles that observed, simulated wind speeds are generally rather lower, due to weaker than observed pressure gradients close to the centres of the simulated storms. Simulations of the effect of climate change are performed. Under enhanced greenhouse conditions, simulated numbers of TCs do not change very much compared with those simulated for the current climate, nor do regions of occurrence. There is a 56% increase in the number of simulated storms with maximum winds greater than 30 m s–1 (alternatively, a 26% increase in the number of storms with central pressures less than 970 hPa). In addition, there is an increase in the number of intense storms simulated south of 30°S. This increase in simulated maximum storm intensity is consistent with previous studies of the impact of climate change on tropical cyclone wind speeds. 相似文献
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该文提出一个热带气旋定量降水预报(QPF) 的动力相似方案。方案应用热带气旋初始参数、历史过程的天气形势场和物理量场及数值预报产品, 构造预报区域内当前时刻至未来时刻环境要素场的多元客观相似判据。通过定义非线性的相似指数综合评估历史热带气旋样本与预报热带气旋在多元判据下的连续动态相似程度, 以此找到相似样本。应用相似样本的历史降水量记录进行相似指数的权重综合, 得到热带气旋未来6~48 h降水量的定点、定量预报值。预报试验表明该方案具有一定的预报技巧。 相似文献
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热带气旋研究和业务预报进展—第九届世界气象组织热带气旋国际研讨会（IWTC-9）综述 总被引：1，自引：0，他引：1
2018年12月3—7日在美国夏威夷召开的第九届世界气象组织热带气旋国际研讨会对国际热带气旋研究和预报预警业务的近期进展进行了充分回顾,并对未来的发展方向进行了系统研讨。过去4年（2015—2018年）,在热带波动和对流对热带气旋生成的影响、复杂环境影响热带气旋路径转向的机理、对流和风垂直切变对热带气旋强度变化的作用机制、双眼墙形成和替换机理、热带气旋变性过程对环境条件的响应、热带气旋气候变化特征、热带气旋多平台观测技术等诸多方面的研究取得了显著进展。同时,在热带气旋生成概率预报、全球模式中热带气旋强度预报改进、热带气旋活动次季节业务预测技术发展以及热带气旋预报不确定性理论等方面也取得积极进展。在综述此次会议的相关议题后,简要讨论中国热带气旋研究和业务发展方向。 相似文献
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In the context of a model of tropical cyclone intensity based on an improved meso-scale atmospheric model, numerical simulation is performed of the track and intensity variation of tropical cyclones(TC) arising from sea surface temperature(SST) variation over a specified sea region. Evidence suggests that the model is capable of modeling quite welt the track and intensity of TC:SST variation leads to an abrupt change in the cyclone intensity:the response of the cyclone to the abrupt SST change lasts 8-12 h. 相似文献
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An objective prediction approach to the 6 h-144 h track and intensity of tropical cyclones over the northwestern Pacific is proposed. On the basis of both analog deviation technique and completed historical sample curve library, the track or intensity prediction for each forecast period are determined respectively through the optimum weighted superposition of displacement or intensity change of the cases, with different number and weighted coefficient corresponding to minimal analog deviation, from different tropical cyclone or different stage of the same cyclone. so that the prediction results for both forecast period and entire process are optimal. The verification suggests that the approach exhibits better forecast performance than other previous forecast methods by having remarkable decreasing forecast errors in short-and medium-range forecast of both track and intensity,and that the approach can also be used to predict effectively the decay process of tropical cyclone and is able to predict anomalous track and tropical depression. 相似文献
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Ulrike Löptien Olga Zolina Sergey Gulev Mojib Latif Vladimir Soloviov 《Climate Dynamics》2008,31(5):507-532
Cyclone activity and life cycle are analysed in the coupled GCMs ECHAM5/OM and ECHAM4/OPYC3. First, the results for the present
climate (1978–1999) are compared with ERA-40 and NCEP/NCAR reanalyses, showing a drastic improvement in the representation
of cyclone activity in ECHAM5/OM compared to ECHAM4/OPYC3. The total number of cyclones, cyclone intensity, propagation velocity
and deepening rates are found to be much more realistic in ECHAM5/OM relative to ECHAM4/OPYC3. Then, changes in extra tropical
cyclone characteristics are compared between present day climate and future climate under the emission-scenario A1B using
ECHAM5/OM. This comparison is performed using the 20-year time slices 1978–1999, 2070–2090 and 2170–2190, which were considered
to be representative for the various climate conditions. The total number of cyclones does not undergo significant changes
in a warmer climate. However, regional changes in cyclone numbers and frequencies are evident. One example is the Mediterranean
region where the number of cyclones in summer increases almost by factor 2. Some noticeable changes are also found in cyclone
life cycle characteristics (deepening rate and propagation velocity). Cyclones in the future climate scenario tend to move
slower and their deepening rate becomes stronger, while cyclone intensity does not undergo significant change in a warmer
climate. Generally, our results do not support the hypothesis of enhanced storminess under future climate conditions. 相似文献
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热带气旋强度变化研究进展 总被引：78，自引：10，他引：68
自20世纪90年代后期以来,热带气旋强度变化研究越来越受到人们的重视,随着研究的不断深入,热带气旋强度变化研究取得了可喜的进展,文中总结近年来热带气旋强度变化的主要研究成果,主要包括(1)热带气旋的发生、发展和最大可能强度的研究;(2)行星涡度梯度、环境均匀流、环境流场垂直切变以及热带气旋外流与环境流的相互作用对热带气旋强度的影响及物理机制;(3)热带气旋结构与强度的变化关系,着重总结环境流场导致的非对称结构变化而引起的热带气旋强度变化以及对涡旋倾斜发展理论验证,分析了涡旋Rossby波的最新研究;(4)海洋热状况变化以及海洋飞沫对热带气旋强度的影响研究成果。分析指出,今后进一步开展用现代化卫星探测资料研究热带气旋强度变化外,还应加强热带气旋外流与环境流场的相互作用,海-气交界面的参数化问题,热带气旋结构变化与TC强度变化关系以及这种关系的物理本质的研究,通过深入研究,认识热带气旋强度变化的物理机制,提高热带气旋强度变化的预报能力。 相似文献
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Previous numerical studies have focused on the combined effect of momentum and scalar eddy diffusivity on the intensity and structure of tropical cyclones. The separate impact of eddy diffusivity estimated by planetary boundary layer(PBL) parameterization on the tropical cyclones has not yet been systematically examined. We have examined the impacts of eddy diffusion of moisture on idealized tropical cyclones using the Advanced Research Weather Research and Forecasting model with the Yonsei University PBL scheme. Our results show nonlinear effects of moisture eddy diffusivity on the simulation of idealized tropical cyclones. Increasing the eddy diffusion of moisture increases the moisture content of the PBL, with three different effects on tropical cyclones:(1) an decrease in the depth of the PBL;(2) an increase in convection in the inner rain band and eyewall; and(3) drying of the lowest region of the PBL and then increasing the surface latent heat flux. These three processes have different effects on the intensity and structure of the tropical cyclone through various physical mechanisms. The increased surface latent heat flux is mainly responsible for the decrease in pressure. Results show that moisture eddy diffusivity has clear effects on the pressure in tropical cyclones, but contributes little to the intensity of wind. This largely influences the wind–pressure relationship, which is crucial in tropical cyclones simulation. These results improve our understanding of moisture eddy diffusivity in the PBL and its influence on tropical cyclones, and provides guidance for interpreting the variation of moisture in the PBL for tropical cyclone simulations. 相似文献
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利用气象灾害普查资料、影响浙江丽水热带气旋的有关历史资料以及历年丽水市的国内生产总值(GDP)统计资料,对1984～2007年影响丽水的热带气旋灾害特征进行统计分析,并应用改进后的气象灾害分级标准,对丽水的热带气旋灾害进行风险评估。结果表明:丽水的热带气旋灾害是各类气象灾害中最严重的;24年中致灾热带气旋年发生频数为1.2个;5、7、8、9、10月均有致灾热带气旋,其中8月气旋个数最多、影响最严重;热带气旋灾害在空间上呈明显的自东南向西北减轻的特点,但各月之间略有差异;热带气旋灾害风险青田最大,松阳最小,且两者之间差异巨大。 相似文献