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1.
Reliable predictions of storm runoff from rainfall and snowmelt are important for flood hazard mitigation and resilience. In this study, the HEC-HMS and PRMS hydrological models have been applied to simulate storm runoff in Taunton River Basin for the storm event in 2010 when maximum rainfall intensity reached approximate 5 in/day in March, and the snowfall reached about 11 inches in December. Model parameters were calibrated, and model performance was evaluated by comparing model-simulated daily stream flow with observations. For the rainstorm period during March–April, results indicate that both HEC-HMS and PRMS provide very good predictions of rainfall runoff with the correlation values above 0.95, and PRMS produces lower root-mean-square errors than those from HEC-HMS. Over the 12-month period including the snowfall in December, the time series of flow by PRMS match better with observations than those from the HEC-HMS. The 12-month overall correlation values for HEC-HMS and PRMS are 0.91 and 0.97 at Bridgewater Station, and 0.89 and 0.97 at Threemile Station, respectively. For an extreme storm scenario of the maximum historical 36.7-inch snowfall in early February in combination with the rainstorm in March–April of 2010, model simulations indicate that the flow would substantially increase by about 50% or more. Comparisons between HEC-HMS and RPMS models have been analyzed to provide references for storm runoff modeling. 相似文献
2.
Stanley A. Changnon 《Natural Hazards》2008,45(1):1-9
Winter storms are a major weather problem in the United States and their losses have been rapidly increasing. A total of 202
catastrophic winter storms involving ice storms, blizzards, and snowstorms, each causing >$5 million in damages, occurred
during 1949–2003, and their losses totaled $35.2 billion (2003 dollars). Catastrophic winter storms occurred in most parts
of the contiguous United States, but were concentrated in the eastern half of the nation where 88% of all storm losses occurred.
They were most frequent in the Northeast climate district (95 storms), and were least frequent in the West district (14 catastrophic
storms). The annual average number of storms is 3.7 with a 1-year high of nine storms, and one year had no storms. Temporal
distributions of storms and their losses exhibited considerable spatial variability across the nation. For example, when storms
were very frequent in the Northeast, they were infrequent elsewhere, a result of spatial differences in storm-producing weather
conditions over time. The time distribution of the nation’s 202 storms during 1949–2003 had a sizable downward trend, whereas
the nation’s storm losses had a major upward trend for the 55-year period. This increase over time in losses, given the decrease
in storm incidences, was a result of significant temporal increases in storm sizes and storm intensities. Increases in storm
intensities were small in the northern sections of the nation, but doubled across the southern two-thirds of the nation, reflecting
a climatic shift in conditions producing intense winter storms. 相似文献
3.
Chew-Hung Chang 《Natural Hazards》2011,56(3):667-679
The 2007 Intergovernmental Panel on Climate Change (IPCC) Assessment Report 4 found an average increase in global surface
temperature of 0.74°C between 1906 and 2005. There is general agreement in the literature that the frequency of extreme precipitation
events in Southeast Asia will increase with global warming. In particular, the potential impact of associated storm hazards
will render the densely populated countries in Southeast Asia vulnerable to such changes in precipitation events. One main
adaptation strategy given such impending changes is preparedness. Using existing literature and historical meteorological
data, this paper establishes that Southeast Asia is indeed experiencing storms of higher intensities and more frequently.
Two case of extreme storm event in Southeast Asia, the extreme high rainfall event in December 2006 in Southern Johor and
Typhoon Vamei, are presented to consider the implications of the increased storm activities due to global warming. These two
examples also discuss the need for preparedness in adapting to the impact of global warming. 相似文献
4.
为研究降雨过程雨强随历时的变化关系,利用中国14个气象站近40年逐分钟降雨资料,采用动态K均值聚类法并根据雨峰在降雨过程中出现的位置,将中国10256次降雨过程分为4种类型,即降雨前期集中型（Ⅰ型）、降雨中期集中型（Ⅱ型）、降雨后期集中型（Ⅲ型）和降雨均匀分布型（IV型）。结果表明:中国Ⅰ型降雨出现频次最高,占47.1%;Ⅱ型次之,占21.2%;Ⅲ型和IV型出现频次相当,分别占15.3%和16.4%。夏季Ⅰ型降雨发生频次占绝对优势,为夏季总降水过程的52.2%;冬季各类雨型发生频次相差不大。Ⅰ型多为短历时高强度降雨,而IV型多为长历时低强度降雨,Ⅱ型和Ⅲ型居中。历时越短时,Ⅰ型降雨的比重越大;随着降雨历时的增加,Ⅰ型降雨的比重明显下降,IV型降雨的比重增加。 相似文献
5.
文章依据冰芯、树木年轮等自然记录和历史文献记录,分析了中国北方不同地区近2000年的沙尘事件及其与气候变化的关系。结果表明,在干旱区西部,历史时期的沙尘变化主要受温度变化的制约,无论在10年尺度,还是百年尺度上,沙尘事件与温度变化均表现为显著的反相关,即气候寒冷期与沙尘频发事件相对应,气候温暖期与沙尘发生变弱期一致;在半干旱区,在10年尺度上温度和降水序列与沙尘发生频率均显著负相关,但在百年尺度上沙尘与降水变化的关系更为密切;在干旱区东部,沙尘与气候变化的关系具有明显的过渡性特征,气候变化对沙尘事件的作用主要在百年尺度上体现出来,沙尘与温度记录的负相关比降水更好,在10年尺度上气候与沙尘序列尽管也是负相关,但不显著。通过对现代气象记录的气温、降水变化和沙尘事件频数分析,其结果与历史时期情况基本一致。 相似文献
6.
The ongoing greenhouse gas buildup and increase in near-surface air temperatures may have an impact on severe weather events in the United States. Output from some numerical modeling simulations suggests that the atmosphere over mid-latitude land areas could become more unstable in the future thereby supporting an increase in convective activity. However, despite the numerical simulation results, empiricists have been unable generally to identify significant increases in overall severe storm activity as measured in the magnitude and/or frequency of thunderstorms, hail events, tornadoes, hurricanes, and winter storm activity across the United States. There is evidence that heavy precipitation events have increased during the period of historical records, but for many other severe weather categories, the trends have been downward over the past half century. Damage from severe weather has increased over this period, but this upward trend disappears when inflation, population growth, population redistribution, and wealth are taken into account. 相似文献
7.
Taking the Taizihe River Basin located in Liaoning Province as a study area, we applied HBV hydrological model to simulate the hydrological process of this river basin with the support of observed daily precipitation, mean temperature, hydrological data in Xiaolinzi hydrologic station, and global digital elevation model data from SRTM3, land utilization types, etc. According to the simulation results of daily runoff, the possible impact of future climate change on runoff was analyzed through forcing HBV model by RegCM4.4 dynamic downscaled climatic data. The results show that HBV model performed generally well for daily simulation of the Taizihe River Basin with Nash Sutcliffe coefficient and deterministic coefficient being all over 0.60 in the calibration period and validation period, and the response of flooding to precipitation were simulated better. This indicates the HBV model can be successfully applied to the Taizihe River Basin. Mean temperature will increase obviously with persistent rising trend by RegCM4.4 model in 2021-2070 under RCP4.5 scenario. Annual precipitation and runoff depth are expected to reduce a bit. Compared with the baseline period (1986-2005), annual runoff depth will increase by 9.79%. At the same time, the runoff depth will increase significantly in summer and autumn. The variation of runoff quantile indicates that both peak extreme runoff and dry extreme runoff will increase to different degrees than that in the baseline period. In the future, the Taizihe River Basin will be likely to experience extreme flooding. 相似文献
8.
全球气候变化背景下,极端水文气象事件发生的频率和强度都受到了直接影响,研究气候变化对极端水文气象事件的影响对防灾减灾和工程设计等至关重要.采用了联合国政府间气候变化专门委员会(IPCC)第四次评估报告中给出的A1B、A2和B1三种温室气体排放情景,选用大气环流模式Had-CM3,利用随机天气发生器LARS-WG生成逐日气象资料,结合P-Ⅲ型曲线和线性矩方法分析计算了钱塘江流域21世纪中叶的设计暴雨情况.结果表明:LARS-WG天气发生器在钱塘江流域有较好的模拟效果;在A1B和B1情景下,钱塘江流域各站点不同重现期下的设计暴雨值基本呈增大趋势,其中A1B情景下杭州站百年一遇的设计暴雨值为209.14mm,比基准期增大11.0％. 相似文献
9.
Kirsten Halsnæs Morten Andreas Dahl Larsen Per Skougaard Kaspersen 《Natural Hazards》2018,94(1):261-278
Least developed countries are generally regarded as particularly sensitive to climate change due to among other vulnerable locations and low adaptation capabilities. In the present study, we address climate change hazards in least developed countries by presenting a methodological framework, which is suitable for the estimation damage costs as a function of risk aversion, equality, income distribution and climate scenario using state-of-the-art climate model projections. As a case study, the methodology is applied to study severe storms in Cambodia based on two future climate scenarios and data on historical damages from storm events, which are used as a proxy in performing a sensitivity analysis on all input parameters. For the assumptions and parameter ranges used here, the study shows a high sensitivity to the income distribution (reflected by discount rates) and risk aversion and smaller effects from equality measures and extreme wind climate scenario. We emphasize that the assumptions on risk aversion reflecting consumption smoothing possibilities of low-income households clearly depicts that climate risks can be particularly high as a consequence of poverty and therefore recommend that context-specific vulnerabilities and equity concerns in climate risk studies should be included when making assessments for least developed countries. 相似文献
10.
The potential impacts of valley fills associated with mountaintop removal/valley fill (MTR/VF) coal mining on downstream flooding in the coalfields of eastern Kentucky and adjacent states are a subject of public debate and scientific uncertainty. This study explored two aspects of this issue. First, hydrologic indices of relative runoff production and surface and subsurface flow detention were applied to conditions typical of headwater and low-order drainage basins in eastern Kentucky. Results show that there is a clear risk of increased flooding (greater runoff production and less surface flow detention) following MTR/VF operations, and suggest that, on balance, valley fills are more likely to increase rather than decrease flood potential. However, there is a wide range of outcomes, qualitatively and quantitatively. Flood risks can be increased or decreased, and the degree of either may vary markedly. The effects of MTR/VF mining on downstream peak flows are highly contingent on local pre- and post-mining conditions, and it would be unwise to apply generalizations to specific sites. Second, the occurrence of flash floods downstream of MTR/VF operations when nearby unmined areas did not flood or had less severe floods has frequently been explained (without supporting data) in terms of locally greater precipitation. The likelihood of such short-range variability of storm precipitation is evaluated by applying the state probability function to NEXRAD radar estimates of precipitation for two 2001 storms which produced flash floods in eastern Kentucky. The spatial structure of the storm precipitation indicates that at the scale of the analysis (pixel size of approximately 2 km) large local variations in storm precipitation are unlikely—that is, the probability of nearby hollows or low-order drainage basins receiving substantially different storm precipitation totals is low. 相似文献
11.
以太子河流域为研究区域,采用HBV水文模型对流域的水文过程进行模拟,并选取RegCM4.4区域气候模式输出的平均气温和降水数据来驱动HBV水文模型,模拟逐日径流过程,分析RCP4.5排放情景下未来太子河流域径流的演变。结果表明,HBV水文模型在太子河流域模拟效果较好,率定期与验证期Nash效率系数与确定性系数均在0.60以上,模型基本模拟出了洪水对降水的响应过程。RCP4.5情景下,2021 2070年太子河流域年平均气温呈持续升温趋势,流域降水和年径流深度呈微弱减少趋势。相较于基准期,年径流深度将增多9.79%,夏季和秋季径流深度上升明显。径流分位数的变化表明,峰值极端径流和枯水极端径流均较基准期有不同程度的增多,未来太子河流域发生极端洪涝的可能性较高。 相似文献
12.
Hydrological modeling of typhoon-induced extreme storm runoffs from Shihmen watershed to reservoir, Taiwan 总被引：1，自引：1，他引：0
Typhoon-induced extreme storm runoffs often cause flood hazards. In this study, a hydrological model (HEC-HMS) was applied to Shihmen watershed located in Taiwan. Three typhoon-induced storm events, with return period ranging from 1 to 90 years, were used in case studies to characterize storm runoff. With a 5-year storm for model calibration, model parameters were carefully calibrated through the comparison between model simulated and observed flows at a stream gage station. The calibrated model was then verified for a 90-year storm and a 1-year storm event. Results indicate that the calibrated and verified HEC-HMS hydrological model is capable of providing satisfactory predictions of the typhoon-induced extreme storm runoff to support reservoir operation and flood hazard mitigation. Based on model simulations, typhoon-induced water table increases for different initial water volumes at Shihmen Reservoir was derived by adding storm-runoff volume to the reservoir’s initial elevation-volume rating curve. Water tables above the top elevation of the dam in the reservoir indicate the need for immediate water releases to avoid the risk of overflow over the dam. 相似文献
13.
The storm impact scale of Sallenger (J Coast Res 890–895, 2000) was tested on a partially engineered beach. This scale is supposed to provide a convenient tool for coastal managers to categorize the storm impact at the shore. It is based on the relation between the elevation of storm wave runup and the elevation of a critical geomorphic or man-made structures in the present study. Two different approaches were tested to estimate the elevation of extreme storm wave runup: (1) a parametric model based on offshore wave conditions and local beach slope and (2) the XBeach process-based model that solves implicitly the runup. The study shows comparisons between impact regimes computed with the two methods and those derived from video observations acquired during 2 weeks while the site was battered by three consecutive storms. Storms scenario including wave conditions with higher return periods and different tidal range were also investigated. The advantages and disadvantages of the two methods used to compute extreme water level are then compared, and guidelines for the development of early warning system are drawn. 相似文献
14.
Space weather prediction involves advance forecasting of the magnitude and onset time of major geomagnetic storms on Earth. In this paper, we discuss the development of an artificial neural network-based model to study the precursor leading to intense and moderate geomagnetic storms, following halo coronal mass ejection (CME) and related interplanetary (IP) events. IP inputs were considered within a 5-day time window after the commencement of storm. The artificial neural network (ANN) model training, testing and validation datasets were constructed based on 110 halo CMEs (both full and partial halo and their properties) observed during the ascending phase of the 24th solar cycle between 2009 and 2014. The geomagnetic storm occurrence rate from halo CMEs is estimated at a probability of 79%, by this model. 相似文献
15.
The Eastern Mediterranean and the Middle East (EMME) is suffering from abnormal cooling of weather conditions and existence of an extreme weather phenomenon known as ice storm Alexa. The present paper investigates the weather conditions over Europe that causes this abnormal weather over the EMME through December of 2013. Daily data sets of several meteorological elements (temperature, precipitation, relative humidity, sea level pressure, and geopotential height at level 500 hPa, etc.) over the northern hemisphere, including Europe and EMME of December of 2013, have been used through the present work. In addition, to that, a time cross section analysis of the daily operational data for meteorological elements (mean surface temperature, temperature and geopotential height at level 500 hPa, relative humidity, precipitation rate, and sea surface pressure) was done over the EMME for December 2013. The methodology of anomaly and correlation coefficient techniques for the data sets has been used. The results uncovered that the EMME has abnormal and very cold weather conditions due to the inference of meridional blocking persisted over Europe and the existence of the extremely negative geopotential height anomaly aloft over Eastern Europe throughout this month. 相似文献
16.
海南岛东南部海岸砂丘风暴冲越沉积记录 总被引：1，自引：0，他引：1
通过海南岛东南部海岸详细的古风暴学考察,在尖岭海岸发现了含有风暴冲越沉积物的海岸沙丘剖面,分别命名为JL-1和JL-2剖面,试图从海岸沙丘沉积记录中提取历史上的风暴事件信息。沉积物粒度、磁化率等参数的指标分析表明,这两个剖面含有典型的风暴冲越沉积物,利用放射性核素AMS14C测年、OSL测年分析,并结合历史文献记载,确定这些风暴沉积层是多次台风作用的产物,其形成机制与风暴浪越过海岸沙丘的堆积有关,风暴流越过沙丘顶部后不能回流,导致风暴流携带的沉积物迅速沉积。此外,依据Stockdon经验公式计算结果,该地点沉积记录所代表的最大风暴事件相当于100到200年一遇的重现期。研究表明,该处海岸沙丘冲越沉积含有南海台风强度与重现期的重要信息。 相似文献
17.
Flood is among the deadliest disasters in India, and the frequency of floods and extreme precipitation events is projected to increase under the warming climate. The frequency of floods in India varies geographically as some regions are more prone to floods than the others. The Kerala flood of 2018 caused enormous economic damage, affected millions of people, and resulted in the death of more than 400 people. Here we provide a hydroclimatological perspective on the Kerala flood of 2018. Using the observations and model simulations from the Variable Infiltration Capacity (VIC) model, we show that the 2018 extreme precipitation and runoff conditions that caused flooding were unprecedented in the record of the past 66 years (1951–2017). Our results show that mean monsoon precipitation has significantly declined while air temperature has significantly increased during 1951–2017 in Kerala. The drying and warming trends during the monsoon season resulted in a declined total runoff in large part of the state in the last 66 years. Apart from the mean hydroclimatic conditions, extreme precipitation, and extreme total runoff have also declined from 1951 to 2017. However, 1 and 2-day extreme precipitation and extreme runoff conditions in August 2018 exceeded substantially from the long-term 95th percentiles recorded during 1951–2017. Since there is no increase in mean and extreme precipitation in Kerala over the last six decades, the extreme event during August 2018 is likely to be driven by anomalous atmospheric conditions due to climate variability rather anthropogenic climate warming. The severity of the Kerala flood of 2018 and the damage caused might be affected by several factors including land use/land cover change, antecedent hydrologic conditions, reservoir storage and operations, encroachment of flood plains, and other natural factors. The impacts of key drivers (anthropogenic and natural) on flood severity need to be established to improve our understanding of floods and associated damage. 相似文献
18.
Balanced Sediment Fluxes in Southern California’s Mediterranean-Climate Zone Salt Marshes 总被引：1，自引：0，他引：1
Jordan A. Rosencranz Neil K. Ganju Richard F. Ambrose Sandra M. Brosnahan Patrick J. Dickhudt Glenn R. Guntenspergen Glen M. MacDonald John Y. Takekawa Karen M. Thorne 《Estuaries and Coasts》2016,39(4):1035-1049
Salt marsh elevation and geomorphic stability depends on mineral sedimentation. Many Mediterranean-climate salt marshes along southern California, USA coast import sediment during El Niño storm events, but sediment fluxes and mechanisms during dry weather are potentially important for marsh stability. We calculated tidal creek sediment fluxes within a highly modified, sediment-starved, 1.5-km2 salt marsh (Seal Beach) and a less modified 1-km2 marsh (Mugu) with fluvial sediment supply. We measured salt marsh plain suspended sediment concentration and vertical accretion using single stage samplers and marker horizons. At Seal Beach, a 2014 storm yielded 39 and 28 g/s mean sediment fluxes and imported 12,000 and 8800 kg in a western and eastern channel. Western channel storm imports offset 8700 kg exported during 2 months of dry weather, while eastern channel storm imports augmented 9200 kg imported during dry weather. During the storm at Mugu, suspended sediment concentrations on the marsh plain increased by a factor of four; accretion was 1–2 mm near creek levees. An exceptionally high tide sequence yielded 4.4 g/s mean sediment flux, importing 1700 kg: 20 % of Mugu’s dry weather fluxes. Overall, low sediment fluxes were observed, suggesting that these salt marshes are geomorphically stable during dry weather conditions. Results suggest storms and high lunar tides may play large roles, importing sediment and maintaining dry weather sediment flux balances for southern California salt marshes. However, under future climate change and sea level rise scenarios, results suggest that balanced sediment fluxes lead to marsh elevational instability based on estimated mineral sediment deficits. 相似文献
19.
依据甘肃兰州市1955-2010年沙尘暴、 浮尘天气事件年变化资料, 划分年强度分级, 应用Markov模型对其不同强度发生概率进行分析, 在此基础上预测和检验了2011年兰州沙尘暴浮尘天气事件的发生概率.结果显示: 2011年沙尘暴发生的特强年、 强烈年、 强发生年、 一般发生年和少发年的概率为,而事实上2011年发生沙尘暴0次,属于少发年, 符合预测结果; 2011年浮尘天气发生的特强年、 强烈年、 强发生年、 一般发生年和少发年的概率为,而事实上2011年发生浮尘9次,介于平常年和少发年范围, 符合预测结果.随着时间序列的延长, Markov模型可成为短期沙尘暴浮尘天气变化预测的有效途径. 相似文献
20.
跨海桥隧工程设计需要推算工程位置不同重现期设计流速,由于现场缺乏长期实测流速资料,设计流速推算存在很大困难。研究提出了采用不同重现期典型风暴潮过程推算河口海岸设计流速的数值模拟方法,对河口地区考虑洪水径流与风暴潮流的耦合。在依据澳门验潮站1925—2003年实测潮位资料分析珠江口海域风暴潮过程特征的基础上,结合潮位和潮差年极值频率分析结果构建了不同重现期典型风暴潮潮型。采用平面二维水动力数学模型模拟了不同重现期风暴潮和上游一般洪水组合条件下珠江口水域的流场,得出港珠澳大桥沿线各控制点处设计流速。 相似文献