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1.
47年来深圳的严重气象灾害及其规律(二)(天气篇)   总被引:3,自引:1,他引:3  
利用深圳47年的各类气候系列资料,分析8~10年一遇的严重气候灾害及其规律,包括冷冬、多雨、多雷暴、干旱、多台风等,用最大熵谱分析方法研究了各序列的周期振荡,同时扼要分析了各类严重天气灾害。  相似文献   

2.
Friuli Venezia Giulia is a region located in the North-Eastern part of Italy. It has the Adriatic Sea (Gulf of Trieste) on the South and the Julian and Carnic Alps surrounding it on the North. For these geographical properties thunderstorms and precipitations are common events in the plain of this region.The climatology of thunderstorms and rainfalls, considering 6 h interval periods, is studied in this work. It is shown how the thunderstorm frequency, based on the recording of at least three lightning strikes during the 6 h period, is 16%. The occurrence frequency of at least 1 mm of rain accumulated in 6 h is 24%, while that of at least 5 mm in 6 h is 14%.The daily and monthly distributions of these events are then stratified in three classes, based on their “intensity” (weak, medium and strong), and the different behaviors are analysed. Finally, an explanation for the main monthly rain frequency is sought by looking at only two sounding-derived indices and in particular at their annual cycles. The two indices (related to the potential instability and to the water vapour flux) attempt to summarize the “convective” and “flux” mechanisms for producing rain. It is found that in some particular periods of the year the rain-originating process seems well identifiable, while in many others the two processes seem to be concomitant.  相似文献   

3.
The year 2021 was recorded as the 6th warmest since 1880. In addition to large-scale warming, 2021 will be remembered for its unprecedented climate extremes. Here, a review of selected high-impact climate extremes in 2021, with a focus on China, along with an extension to extreme events in North America and Europe is presented. Nine extreme events that occurred in 2021 in China are highlighted, including a rapid transition from cold to warm extremes and sandstorms in spring, consecutive drought in South China and severe thunderstorms in eastern China in the first half of the year, extremely heavy rainfall over Henan Province and Hubei Province during summer, as well as heatwaves, persistent heavy rainfall, and a cold surge during fall. Potential links of extremes in China to four global-scale climate extremes and the underlying physical mechanisms are discussed here, providing insights to understand climate extremes from a global perspective. This serves as a reference for climate event attribution, process understanding, and high-resolution modeling of extreme events.  相似文献   

4.
我国南方雷暴的气候特征研究   总被引:52,自引:5,他引:52  
徐桂玉  杨修群 《气象科学》2001,21(3):299-307
本文根据我国南方62个气象观测着1971-995年月雷暴日数资料,应用EOF和小波统计分析方法,研究了雷暴的气候特征,包括它们的空间分布类型、季节变化特征和年际变化规律,所得结论,为进一步探讨大范围雷暴与大气环流的联系打下了基础。  相似文献   

5.
The climate tourism potential of a region can be described by methods used in human biometeorology and applied climatology. Frequency analyses based on complex thermal bioclimatic indices (e.g. physiologically equivalent temperature) and diagrams of precipitation patterns based on thresholds offer new approaches of visualisation. An integral approach for tourism climatologic analyses is provided by the climate?Ctourism/transfer?Cinformation?Cscheme that also bases on frequency distributions of relevant factors and parameters which are important for a destination. The knowledge about the vertical variability of tourism climatologic factors is of high importance because of the several kinds of tourism activities affected by weather. The same holds for a quantification of extreme events like heat waves because of their possible effects on health and recreation over a year's course. The results show that the vertical gradient of bioclimatic and tourism-related parameters can be of value when developing strategies of adaption to climate change.  相似文献   

6.
This study assesses future climate change over East Asia using the Global/Regional Integrated Model system—Regional Model Program (RMP). The RMP is forced by two types of future climate scenarios produced by the Hadley Center Global Environmental Model version 2 (HG2); the representative concentration pathways (RCP) 4.5 and 8.5 scenarios for the intergovernmental panel on climate change fifth assessment report (AR5). Analyses for the current (1980–2005) climate are performed to evaluate the RMP’s ability to reproduce precipitation and temperature. Two different future (2006–2050) simulations are compared with the current climatology to investigate the climatic change over East Asia centered in Korea. The RMP satisfactorily reproduces the observed seasonal mean and variation of precipitation and temperature. The spatial distribution of the simulated large-scale features and precipitation by the RMP is generally less reflective of current climatic conditions than that is given by the HG2, but their inter-annual variations in East Asia are better captured by the RMP. Furthermore, the RMP shows higher reproducibility of climate extremes including excessive heat wave and precipitation events over South Korea. In the future, strong warming is distinctly coupled with intensified monsoonal precipitation over East Asia. In particular, extreme weather conditions are increased and intensified over South Korea as follows: (1) The frequency of heat wave events with temperature greater than 30 °C is projected to increase by 131 and 111 % in the RCP 8.5 and 4.5 downscaling, relative to the current climate. (2) The RCP 8.5 downscaling shows the frequency and variability of heavy rainfall to increase by 24 and 31.5 %, respectively, while the statistics given by the RCP 4.5 downscaling are similar to those of the current climate.  相似文献   

7.
利用2010-2018年全球闪电定位网(WWLLN)观测资料,采用基于闪电密度的空间聚类算法(DBSCAN)建立了西北太平洋地区雷暴数据集,研究了该区域雷暴的时空分布特征,并进行海陆差异对比.研究结果表明,在合理设定DBSCAN参数阈值的条件下,基于WWLLN闪电聚类的雷暴与天气雷达观测在时空分布和过程演变上具有一致性...  相似文献   

8.
2003年全球重大天气与气候事件   总被引:3,自引:0,他引:3  
王丽华 《气象》2004,30(4):25-28
全球气候持续偏暖。南亚、欧洲大部和北美洲冬季出现异常严寒 ,许多地区遇到数十年未见的暴风雪 (雨 )天气。夏季欧亚大陆和北美的多个国家出现持续高温酷热天气 ,严重干旱导致森林火灾频发 ,经济损失惨重。南亚、东南亚夏季暴雨频繁 ,造成严重洪涝灾害。非洲干旱持续 ,局部发生洪涝。美国 5月遭受特大龙卷风袭击 ,北大西洋飓风较常年显著偏多。  相似文献   

9.
47年来深圳的严重气象灾害及其规律(一)(气候篇)   总被引:7,自引:2,他引:7  
利用深圳47年的各类气候系列资料,分析了约8~10年一遇的严重气候灾害及其规律,包括冷冬、多雨、多雷暴、干旱、多台风等,用最大熵谱分析方法研究了各序列的周期振荡,同时扼要分析了各类严重天气灾害。  相似文献   

10.
从一般雷暴、灾害性雷暴和台风的闪电活动特征以及雷暴闪电尺度特征四个方面对相关研究进行梳理.一般雷暴通常具有正常极性电荷结构,云/地闪比例在3左右(中纬度地区),地闪中正地闪占比为10%左右,负地闪位置往往更集中于对流区.灾害性雷暴倾向具有活跃的云闪,低比例的地闪,易出现反极性电荷结构,正地闪比例偏高.闪电活动与灾害性天...  相似文献   

11.
红色精灵是一种发生于闪电放电活跃的雷暴云上空的中高层大气瞬态发光现象,它们通常由中尺度对流系统层状云降水区内的强地闪回击产生,是对流层和中间层之间的一种能量耦合过程.目前,有关中国南海及东南亚地区的红色精灵观测鲜有报道.为了进一步了解热带地区产生红色精灵事件的沿海性雷暴特征,于2019年利用低光度光学观测系统和低频磁场...  相似文献   

12.
新一代天气雷达超级单体风暴中气旋特征分析   总被引:4,自引:0,他引:4  
超级单体风暴常伴随着冰雹、雷雨大风等强对流天气,最本质的特征是有一持久深厚的几千米尺度的涡旋——中气旋。利用2003--2009年福建龙岩新一代天气雷达观测到的32次超级单体风暴,分析了超级单体风暴中气旋的时空分布、结构特征以及旋转速度大小、中气旋顶和底的高度、伸长厚度以及切变值等特征量。结果表明:90%以上的超级单体中尺度气旋是与冰雹、雷雨大风、短时强降水等强对流天气相联系的。统计8次有详细灾情的雷雨大风或冰雹天气过程发现,中气旋强度不断加强,中气旋厚度加大,最强切变中心突降时将产生大风或冰雹等强对流天气。  相似文献   

13.
14.
This paper contributes to the literature underscoring the importance of climatic variance by developing a framework for incorporating the means and tails of the distributions of rainfall and temperature into empirical models of agricultural production. The methodology is applied to estimate the impact of climate change on the discrete choice decision to adopt irrigation since it is an important adaptation to climate change. We develop a discrete choice model for the decision to install irrigation capacity that captures the effects of both climate means and extremes. Climatic means and frequencies of climatic events in the upper tails of the temperature and precipitation distributions are used to estimate the parameters of a normal distribution for temperature and a Weibull distribution for precipitation. Using estimates from a probit model, we examine the independent effects of changing climatic mean and variance on the probability of adopting irrigation. Increasing the mean temperature, holding variance constant, shifts the entire distribution toward warmer temperatures—increasing the frequency of extreme temperatures. For precipitation, the specification captures the separate effects of mean rainfall, frequency of rainfall, and frequency of extreme events. The results show that the tails of the temperature and precipitation distributions, not the means, are the dominant climatic determinants in irrigation adoption. The results also show that water availability, soil characteristics, farm size and operator demographics are important determinants of irrigation.  相似文献   

15.
The historical frequency, distribution and impact of tropical cyclones, severe thunderstorms and bushfires in Australia are discussed. Although the climatological record of frequency and distribution is incomplete for some hazards, this information is more reliable than that available on the impacts of the hazards. Insurance payout costs form the best quantitative measure of negative impacts, but such figures represent only a fraction of the true costs of damage from severe weather. For tropical cyclones the insurance payout since 1967 has been $1715 million, for severe thunderstorms $1808 million and for bushfires $488 million. Tropical cyclones and storms each result in the loss of 4 to 6 lives each year, while bushfires have an average annual death toll of about 10. Although significant benefits arising from severe weather events can also be identified, quantitative estimates of their alue are not available.  相似文献   

16.
根据1961~2000年武威站雷暴天气实况资料分析了河西走廊东部40年强雷暴天气发生的气候规律,并研究了河西走廊东部强雷暴天气发生的4种环流背景及4种主要天气条件,归纳总结出其短期预报着眼点,为雷暴天气预报业务系统的研制奠定了基础。  相似文献   

17.
De Li Liu  Heping Zuo 《Climatic change》2012,115(3-4):629-666
This paper outlines a new statistical downscaling method based on a stochastic weather generator. The monthly climate projections from global climate models (GCMs) are first downscaled to specific sites using an inverse distance-weighted interpolation method. A bias correction procedure is then applied to the monthly GCM values of each site. Daily climate projections for the site are generated by using a stochastic weather generator, WGEN. For downscaling WGEN parameters, historical climate data from 1889 to 2008 are sorted, in an ascending order, into 6 climate groups. The WGEN parameters are downscaled based on the linear and non-linear relationships derived from the 6 groups of historical climates and future GCM projections. The overall averaged confidence intervals for these significant linear relationships between parameters and climate variables are 0.08 and 0.11 (the range of these parameters are up to a value of 1.0) at the observed mean and maximum values of climate variables, revealing a high confidence in extrapolating parameters for downscaling future climate. An evaluation procedure is set up to ensure that the downscaled daily sequences are consistent with monthly GCM output in terms of monthly means or totals. The performance of this model is evaluated through the comparison between the distributions of measured and downscaled climate data. Kruskall-Wallis rank (K-W) and Siegel-Tukey rank sum dispersion (S-T) tests are used. The results show that the method can reproduce the climate statistics at annual, monthly and daily time scales for both training and validation periods. The method is applied to 1062 sites across New South Wales (NSW) for 9 GCMs and three IPCC SRES emission scenarios, B1, A1B and A2, for the period of 1900–2099. Projected climate changes by 7 GCMs are also analyzed for the A2 emission scenario based on the downscaling results.  相似文献   

18.
Performance of a multi-RCM ensemble for South Eastern South America   总被引:1,自引:1,他引:0  
The ability of four regional climate models to reproduce the present-day South American climate is examined with emphasis on La Plata Basin. Models were integrated for the period 1991–2000 with initial and lateral boundary conditions from ERA-40 Reanalysis. The ensemble sea level pressure, maximum and minimum temperatures and precipitation are evaluated in terms of seasonal means and extreme indices based on a percentile approach. Dispersion among the individual models and uncertainties when comparing the ensemble mean with different climatologies are also discussed. The ensemble mean is warmer than the observations in South Eastern South America (SESA), especially for minimum winter temperatures with errors increasing in magnitude towards the tails of the distributions. The ensemble mean reproduces the broad spatial pattern of precipitation, but overestimates the convective precipitation in the tropics and the orographic precipitation along the Andes and over the Brazilian Highlands, and underestimates the precipitation near the monsoon core region. The models overestimate the number of wet days and underestimate the daily intensity of rainfall for both seasons suggesting a premature triggering of convection. The skill of models to simulate the intensity of convective precipitation in summer in SESA and the variability associated with heavy precipitation events (the upper quartile daily precipitation) is far from satisfactory. Owing to the sparseness of the observing network, ensemble and observations uncertainties in seasonal means are comparable for some regions and seasons.  相似文献   

19.
王婷波  周康辉  郑永光 《气象》2020,46(2):189-199
基于2010—2014年国家闪电监测网的云-地闪电定位数据,利用雷暴识别与追踪算法获得了505 257个雷暴系统,进而统计分析了我国中东部地区的雷暴发生发展特征。考虑地形和气候差异,将我国中东部划分为东北、华北、华中与华东、西南、华南五个区域,对比了上述区域的雷暴中地闪活动持续时间、移动距离、移动速度等特征,并进一步对雷暴发生的环境物理量特征进行了统计分析,最后讨论了雷暴发生与地形的相关关系。结果显示:雷暴具有局地性强、快速生消的特性,超过70%的雷暴移动速度低于60 km·h~(-1),超过80%的雷暴持续时间低于2 h,超过90%的雷暴移动距离低于60 km;东北地区雷暴移动速度相对更快,西南地区移速较慢且雷暴移动距离更短。华中与华东、华南地区雷暴发生的整层可降水量与对流有效位能值最高,西南次之,东北与华北地区最低,而0~6 km垂直风切变则反之;广东、海南等地为雷暴发生最活跃区域,江南、西南地区东部、华南地区西部、华北地区太行山一带等地为雷暴发生较为活跃的地区;雷暴发生与地形密切相关,四川盆地西麓与珠江三角洲地区明显呈现出随地形抬升而导致雷暴触发的情况。  相似文献   

20.
Summary A new statistical method for regional climate simulations is introduced. Its simulations are constrained only by the parameters of a linear regression line for a characteristic climatological variable. Simulated series are generated by resampling from segments of observation series such that the resulting series comply with the prescribed regression parameters and possess realistic annual cycles and persistence. The resampling guarantees that the simulated series are physically consistent both with respect to the combinations of different meteorological variables and to their spatial distribution at each time step. The resampling approach is evaluated by means of a cross validation experiment for the Elbe river basin: Its simulations are compared both to an observed climatology and to data simulated by a dynamical RCM. This cross validation shows that the approach is able to reproduce the observed climatology with respect to statistics such as long-term means, persistence features (e.g., dry spells) and extreme events. The agreement of its simulations with the observational data is much closer than for the RCM data. Correspondence: B. Orlowsky, Potsdam Institute for Climate Impact Research, P.O. Box 60 12 03, 14412 Potsdam, Germany  相似文献   

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