Regionalization of heavy rainfall to improve climatic design values for infrastructure: case study in Southern Ontario,Canada     

Edson Paixao  Heather Auld  M. Monirul Qader Mirza  Joan Klaassen  Mark W. Shephard 《水文科学杂志》2013,58(7):1067-1089

Abstract

Southern Ontario, Canada, has been impacted in recent years by many heavy rainfall and flooding events that have exceeded existing historical estimates of infrastructure design rainfall intensity–duration–frequency (IDF) values. These recent events and the limited number of short-duration recording raingauges have prompted the need to research the climatology of heavy rainfall events within the study area, review the existing design IDF methodologies, and evaluate alternative approaches to traditional point-based heavy rainfall IDF curves, such as regional IDF design values. The use of additional data and the regional frequency analysis methodology were explored for the study area, with the objective of validating identified clusters or homogeneous regions of extreme rainfall amounts through Ward's method. As the results illustrate, nine homogeneous regions were identified in Southern Ontario using the annual maximum series (AMS) for daily and 24-h rainfall data from climate and rate-of-rainfall or tipping bucket raingauge (TBRG) stations, respectively. In most cases, the generalized extreme value and logistic distributions were identified as the statistical distributions that provide the best fit for the 24-h and sub-daily rainfall data in the study area. A connection was observed between extreme rainfall variability, temporal scale of heavy rainfall events and location of each homogeneous region. Moreover, the analysis indicated that scaling factors cannot be used reliably to estimate sub-daily and sub-hourly values from 24- and 1-h data in Southern Ontario.

Citation Paixao, E., Auld, H., Mirza, M.M.Q., Klaassen, J. & Shephard, M.W. (2011) Regionalization of heavy rainfall to improve climatic design values for infrastructure: case study in Southern Ontario, Canada. Hydrol. Sci. J. 56(7), 1067–1089.  相似文献   

Improving the calibration strategy of the physically-based model WaSiM-ETH using critical events     

Shailesh Kumar Singh  Jiaying Liang  András Bárdossy 《水文科学杂志》2013,58(8):1487-1505

Abstract

The use of a physically-based hydrological model for streamflow forecasting is limited by the complexity in the model structure and the data requirements for model calibration. The calibration of such models is a difficult task, and running a complex model for a single simulation can take up to several days, depending on the simulation period and model complexity. The information contained in a time series is not uniformly distributed. Therefore, if we can find the critical events that are important for identification of model parameters, we can facilitate the calibration process. The aim of this study is to test the applicability of the Identification of Critical Events (ICE) algorithm for physically-based models and to test whether ICE algorithm-based calibration depends on any optimization algorithm. The ICE algorithm, which uses the data depth function, was used herein to identify the critical events from a time series. Low depth in multivariate data is an unusual combination and this concept was used to identify the critical events on which the model was then calibrated. The concept is demonstrated by applying the physically-based hydrological model WaSiM-ETH on the Rems catchment, Germany. The model was calibrated on the whole available data, and on critical events selected by the ICE algorithm. In both calibration cases, three different optimization algorithms, shuffled complex evolution (SCE-UA), parameter estimation (PEST) and robust parameter estimation (ROPE), were used. It was found that, for all the optimization algorithms, calibration using only critical events gave very similar performance to that using the whole time series. Hence, the ICE algorithm-based calibration is suitable for physically-based models; it does not depend much on the kind of optimization algorithm. These findings may be useful for calibrating physically-based models on much fewer data.

Editor D. Koutsoyiannis; Associate editor A. Montanari

Citation Singh, S.K., Liang, J.Y., and Bárdossy, A., 2012. Improving calibration strategy of physically-based model WaSiM-ETH using critical events. Hydrological Sciences Journal, 57 (8), 1487–1505.  相似文献   

Design event selection in bivariate hydrological frequency analysis     

E. Volpi  A. Fiori 《水文科学杂志》2013,58(8):1506-1515

Abstract

In the bivariate analysis of hydrological events, such as rainfall storms or flood hydrographs, the choice of an appropriate return period for structure design leads to infinite combinations of values of the related random variables (e.g. peak and volume in the analysis of floods). These combinations are generally not equivalent, from a practical point of view. In this paper, a methodology is proposed to identify a subset of the critical combinations set that includes a fixed and arbitrarily chosen percentage in probability of the events, on the basis of their probability of occurrence. Therefore, several combinations can be selected within the subset, taking into account the specific characteristic of the design problem, in order to evaluate the effects of different hydrological loads on a structure. The proposed method is applicable to any type of bivariate distribution, thus providing a simple but effective rule to narrow down the infinite possible choices for the hydrological design variables. In order to illustrate how the proposed methodology can be easily used in practice, it is applied to a study case in the context of bivariate flood frequency analysis.

Editor Z.W. Kundzewicz; Associate editor Sheng Yue

Citation Volpi, E. and Fiori, A., 2012. Design event selection in bivariate hydrological frequency analysis. Hydrological Sciences Journal, 57 (8), 1506–1515.  相似文献   

The nature of rainfall in the main drainage sub-basins of Uganda     

Francis W.N. Nsubuga  O.J. Botai  Jane M. Olwoch  C.J. deW Rautenbach  Yvette Bevis  Adebayo O. Adetunji 《水文科学杂志》2013,58(2):278-299

Abstract

A study of rainfall trends and temporal variations within seven sub-basins of Uganda spanning from 1940 to 2009 has been made. Rainfall climatologies are constructed from observational data, using 36 station records which reflect hydroclimatic conditions. Long-term changes in rainfall characteristics were determined by non-parametric tests (Mann-Kendall and Sen’s T tests), coefficient of variation (CV), precipitation concentration index and drought severity index. Magnitude of change was estimated by applying Sen’s estimator of slope. Decadal variability of rainfall with marked seasonal cycles is evident. Temporal variability of drought patterns is detected. Variations in annual rainfall are low with no significant trends observed in the main drainage sub-basins. Significant trends occur in October, November, December and January. A noticeable decrease in the annual total rainfall was observed mostly in northwestern and southwestern sub-basins. Rainfall trend in the second normal of June–July–August (JJA) was decreasing in all the main drainage sub-basins.

Editor Z.W. Kundzewicz; Associate editor S. Yue

Citation Nsubuga, F.W.N., Botai, O.J., Olwoch, J.M., Rautenbach, C.J.deW., Bevis, Y., and Adetunji, A.O., 2014. The nature of rainfall in the main drainage sub-basins of Uganda. Hydrological Sciences Journal, 59 (2), 278–299.  相似文献   

塔里木河流域干湿变化与大气环流关系          下载免费PDF全文

陶辉  毛炜峄  黄金龙  翟建青 《水科学进展》2014,25(1):45-52

基于塔里木河流域39个气象站1961—2010年逐日观测数据和NCEP/NCAR再分析数据,采用标准化降水蒸散指数（Standardized Precipitation Evapotranspiration Index,SPEI）,分析了该流域近50年来干湿时空变化特征及典型干湿月份和突变前后的大气环流特征。对SPEI序列进行的趋势检验和突变分析表明,近50年来,塔里木河流域显著变湿并在1986年发生显著突变,SPEI上升趋势显著的站点较多的月份主要集中在暖季（5~10月）。对突变前后不同等级干湿事件频率变化的统计结果表明,突变后,极端干旱事件发生频率略有增加,但轻度和中度干旱事件发生频率有所减少,而不同等级的湿事件发生频率则一致地表现为增加。对典型干湿月份和突变前后对应的北半球500hPa位势高度场和风场变化的合成分析表明,暖季典型干湿月份环流系统配置存在明显差异,增加的水汽和弱不稳定大气层结构是该区域1986年后暖季变湿的原因之一。  相似文献   

淮河流域近500年洪旱事件演变特征分析   总被引：1，自引：0，他引：1  

杨传国  陈喜  张润润  胡琪  余钟波  郝振纯  林朝晖 《水科学进展》2014,25(4):503-510

为了认识淮河流域过去500年洪旱事件发生规律并鉴别当前的洪旱情势,收集并对比分析了流域实测降雨资料、重建历史雨季降雨资料、历史旱涝等级资料、历史洪旱文献记录和历史调查洪水资料等多源洪旱灾害数据。以重建历史雨季降雨资料和历史旱涝等级资料为主要依据,通过滑动平均、频率计算、小波分析和突变检验等方法,分析流域过去500年洪水干旱时空分布特征和演变规律。结果表明,17世纪淮河流域洪旱灾害最严重,但20世纪极端洪旱事件发生频次最多。淮河流域洪旱事件存在40年左右的稳定长周期,主周期从18世纪的15~20年逐渐减少到19世纪的5年周期,近20年来出现2~3年的主周期,洪旱灾害事件呈增加趋势,流域社会经济发展面临着严峻的洪旱灾害威胁。  相似文献   

大洋洲地区大地构造格架与优势矿产资源   总被引：1，自引：0，他引：1  

姚仲友  王天刚  傅朝义  马春  齐立平  孔红杰  汪传胜  李文光  陈刚 《中国区域地质》2014,(2):143-158

大洋洲横跨印澳板块、太平洋板块和欧亚板块三大板块,区内从太古宙至今经历了漫长的构造演化历史。根据区域地质特征,该区可划分为3个一级构造单元,即澳大利亚中西部前寒武纪克拉通、澳大利亚东部古生代造山带和环太平洋中新生代岛弧区,12个二级构造单元和40个三级构造单元。3个一级构造单元由于经历了不同的构造演化过程,各自发育了不同的岩石组合和矿化作用。在研究区域构造演化与成矿作用耦合关系的基础上,总结出3个构造单元的成矿特征：澳大利亚中西部前寒武纪克拉通成矿过程与克拉通的生长有关,成矿时代主要为太古宙和元古宙,优势矿种为金、铜、镍、锰、铁、铀、稀土、铅锌、铝土等;东部古生代造山带成矿多和古太平洋与古冈瓦纳板块的相互作用有关,成矿时代为古生代,优势矿种为铜、金、铅锌和钨锡;环太平洋中新生代岛弧区的成矿作用多与印澳板块、欧亚板块与太平洋板块的相互作用有关,成矿时代多集中在中一更新世,优势矿种为铜、金、镍、钴等。对大洋洲地区矿产资源潜力进行了评估,认为大洋洲地区的铁、锰、铜、铝、镍、金、铀、稀土等矿产资源均具有较好的潜力。  相似文献   

近20年台风事件对黄渤海颗粒有机碳季节性的影响     

王秀君  王晓雯  尤再进  石洪源 《海洋与湖沼》2022,53(4):861-871

边缘海初级生产力普遍较高,有机碳在沉积物中的埋藏高达全球的80%。黄渤海是位于我国东部的一个半封闭的温带陆架边缘海,在近20年中,黄渤海经历的台风事件频率不断增大,对碳循环关键过程发生多重影响。文章利用多组卫星及再分析资料,围绕2003~2020年期间夏季台风过境对黄渤海关键环境变量的影响,分析生物和非生物过程对不同海域水体中颗粒有机碳的贡献。结果表明,夏季台风过境一次、两次对黄渤海叶绿素的影响没有明显差异,叶绿素浓度增加主要在渤海西南部和南黄海约50%的海域。总体上看,台风过境对渤海、北黄海大部分海域水体中颗粒有机碳影响不大,但两次台风过境引起了南黄海约80%的离岸海域颗粒有机碳浓度的显著增加。南黄海中部海域水体中颗粒有机碳与叶绿素的比值在台风过后明显降低,表明该海域颗粒有机碳浓度的提高主要是由生物固碳过程的增强引起。台风过境加剧了黄海与渤海、近岸与离岸的水流交换,此过程增强了高营养盐和有机物水向南黄海尤其是中部海域的输送,因而提高了南黄海大部分海域颗粒有机碳浓度。除了光合作用等生物过程及水流交换对颗粒有机碳有影响外,黄渤海水体中颗粒有机碳浓度还受到沉积物再悬浮、陆源有机碳输入等过程的影响。台风过境可以加剧沉积物再悬浮和陆源有机物的输入,进一步提高黄渤海近岸及离岸海域颗粒有机碳的浓度。  相似文献   

Comparison of nominal and standardized catch per unit effort data in quantifying habitat suitability of skipjack tuna in the equatorial Pacific Ocean     

Cheng Zhou  Yuanyuan Hu  Jie Cao  Liuxiong Xu  Xuefang Wang  Rong Wan  Yu Xiao  Jiangfeng Zhu  Hao Tang 《海洋学报(英文版)》2022,41(3):1-2

In the western and central Pacific Ocean, upper strata waters exhibit highly dynamic oceanographic features under ENSO variability. This has been proved to be responsible for the dynamic change of both abundance and zonal distribution of skipjack tuna(Katsuwonus pelamis). Although causality has been suggested by researchers using physical–biological interaction models, cumulative evidence needs to be obtained and the tenability of assertion needs to be tested from an ecological habitat perspecti...  相似文献   

气象干旱对中亚棉花产量的影响     

徐杨  李秀芬  葛全胜  郝志新 《地理学报》2022,77(9):2338-2352

极端干旱事件频发对中亚棉花生产具有重要影响。本文利用乌兹别克斯坦赞格阿塔实验站棉花大田试验数据评估了APSIM-Cotton模型的适用性,根据CMIP6气候模式模拟的SSP1-2.6、SSP3-7.0和SSP5-8.5等3种共享社会经济路径下的气候变化数据集,分析了2021—2090年SPEI-3干旱指数的变化特征,进而利用APSIM-Cotton模型模拟了考虑CO₂肥效作用的气象干旱对棉花产量的影响。结果表明：APSIM-Cotton模型能够准确模拟乌兹别克斯坦塔什干地区的生育期和产量变化趋势;未来塔什干地区呈现温度明显升高、干旱发生频率明显增加的特征;气象干旱将导致棉花产量下降,SSP1-2.6、SSP3-7.0和SSP5-8.5等3种排放情景下,严重气象干旱导致2021—2050年棉花产量较1961—1990年分别下降28.0%、29.6%和32.1%,2061—2090年棉花分别减产31.5%、33.1%和35.7%,在SSP3-7.0和SSP5-8.5情景下,极端气象干旱导致2061—2090年棉花产量分别下降41.3%和54.2%;CO₂浓度升高可提高棉花产量,贡献率为14.9%~25.0%,但浓度达到750 µmol/mol以上时,棉花增产幅度将不再持续增加。  相似文献