Configurations of community in flood risk management     

Aleksi Räsänen  Vera Kauppinen  Sirkku Juhola  Gunhild Setten  Haakon Lein 《Norsk geografisk tidsskrift. Norwegian journal of geography》2020,74(3):165-180

ABSTRACT

Despite a notable increase in the literature on community resilience, the notion of ‘community’ remains underproblematised. This is evident within flood risk management (FRM) literature, in which the understanding and roles of communities may be acknowledged but seldom discussed in any detail. The purpose of the article is to demonstrate how community networks are configured by different actors, whose roles and responsibilities span spatial scales within the context of FRM. Accordingly, the authors analyse findings from semi-structured interviews, policy documents, and household surveys from two flood prone areas in Finnish Lapland. The analysis reveals that the ways in which authorities, civil society, and informal actors take on multiple roles are intertwined and form different types of networks. By implication, the configuration of community is fuzzy, elusive and situated, and not confined to a fixed spatiality. The authors discuss the implications of the complex nature of community for FRM specifically, and for community resilience more broadly. They conclude that an analysis of different actors across scales contributes to an understanding of the configuration of community, including community resilience, and how the meaning of community takes shape according to the differing aims of FRM in combination with differing geographical settings.  相似文献   

扬子陆块~2.0 Ga的区域变质事件对南北黄陵古元古代差异演化的启示     

陈超  苑金玲  郭盼  黎方云  孔令耀  杨金香  毛新武 《中国地质》2020,47(4):899-913

扬子陆核黄陵地区发育较为完整的太古宙—古元古代片麻岩、表壳岩组合(即崆岭杂岩),前人调查研究认为南北黄陵Ar-Pt1具有一致的物质组成和地质演化过程。笔者分别对南北黄陵太古宙花岗质片麻岩进行锆石年代学研究发现,北黄陵2件样品(HL013-1、HL013-2)均存在大量锆石发育岩浆核-变质边结构,都获得～2.8 Ga原岩结晶年龄和～2.0 Ga变质年龄;而南黄陵1件样品(HL005-3)以具振荡环带结构的岩浆锆石为主,仅获得～2.9 Ga原岩结晶年龄。结合前人研究成果发现,～2.0 Ga的变质年龄在北黄陵太古宙—古元古代的花岗片麻岩、表壳岩中广泛发育,而在南黄陵相似建造中均未获得,一定程度上说明北黄陵地区广泛遭受～2.0 Ga的区域变质作用而南黄陵不发育,南北黄陵在古元古代可能处在不同地块或者同一地块不同部位。2.1～1.6 Ga的构造岩浆事件的分布特点说明扬子陆块可能存在多条古元古代造山带,扬子陆块古元古代以多块体拼贴为特点,广泛记录2.1～1.6 Ga的构造岩浆事件说明扬子陆块是全球哥伦比亚超大陆的重要组成部分。  相似文献   

Obtaining the distribution of quiescent periods directly from the power spectral densities of Sea waves     

《Applied Ocean Research》2019

There is a growing practical interest in the ability to increase the sea states at which marine operations can be safely undertaken by exploiting the quiescent periods that are well known to exist under a wide range of sea conditions. While the actual prediction of quiescent periods at sea for the control of operations is a deterministic process, the long term planning of future maritime tasks that rely on these quiescent periods is a statistical process involving the anticipated quiescence properties of the forecasted sea conditions in the geographical region of interest. It is in principle possible to obtain such data in tabular form either large scale simulation or from field data. However, such simulations are computationally intensive and libraries of appropriate field data are not common. Thus, it is clearly attractive to develop techniques that exploit standard wave spectral models for describing the quiescence statistics directly from such spectra. The present study focuses upon such techniques and is a first step towards the production of a computationally low-cost quiescence prediction tool and compares its efficacy against simulations. Two significant properties emerge for a large class of wave spectral models that encompasses the ubiquitous Neumann and Pierson Moskowitz or Bretschneider forms. Firstly, the auto-correlation function of the wave profile that are required to produce the quiescence property can be obtained analytically in terms of standard special functions. This considerably reduces the computational cost making desktop computer-based planning tools a reality. Secondly, for each class of these parametric spectra, the probability of a given number of consecutive wave heights (normalised to the significant wave heights) less than some critical value is in fact independent of absolute wave height. Thus, for a broad class of practically interesting wave spectra all that is required to obtain the statistical distribution of the quiescent periods is simple rescaling.  相似文献   

A novel approach to leveraging social media for rapid flood mapping: a case study of the 2015 South Carolina floods     

Zhenlong Li  Cuizhen Wang  Christopher T. Emrich  Diansheng Guo 《制图学和地理信息科学》2018,45(2):97-110

Rapid flood mapping is critical for local authorities and emergency responders to identify areas in need of immediate attention. However, traditional data collection practices such as remote sensing and field surveying often fail to offer timely information during or right after a flooding event. Social media such as Twitter have emerged as a new data source for disaster management and flood mapping. Using the 2015 South Carolina floods as the study case, this paper introduces a novel approach to mapping the flood in near real time by leveraging Twitter data in geospatial processes. Specifically, in this study, we first analyzed the spatiotemporal patterns of flood-related tweets using quantitative methods to better understand how Twitter activity is related to flood phenomena. Then, a kernel-based flood mapping model was developed to map the flooding possibility for the study area based on the water height points derived from tweets and stream gauges. The identified patterns of Twitter activity were used to assign the weights of flood model parameters. The feasibility and accuracy of the model was evaluated by comparing the model output with official inundation maps. Results show that the proposed approach could provide a consistent and comparable estimation of the flood situation in near real time, which is essential for improving the situational awareness during a flooding event to support decision-making.  相似文献   

From China’s Heavy Precipitation in 2020 to a “Glocal” Hydrometeorological Solution for Flood Risk Prediction     

Huan WU  Xiaomeng LI  Guy J.-P.SCHUMANN  Lorenzo ALFIERI  Yun CHEN  Hui XU  Zhifang WU  Hong LU  Yamin HU  Qiang ZHU  Zhijun HUANG  Weitian CHEN  Ying HU 《大气科学进展》2021,38(1):1-7

The prolonged mei-yu/baiu system with anomalous precipitation in the year 2020 has swollen many rivers and lakes,caused flash flooding,urban flooding and landslides,and consistently wreaked havoc across large swathes of China,particularly in the Yangtze River basin.Significant precipitation and flooding anomalies have already been seen in magnitude and extension so far this year,which have been exerting much higher pressure on emergency responses in flood control and mitigation than in other years,even though a rainy season with multiple ongoing serious flood events in different provinces is not that uncommon in China.Instead of delving into the causes of the uniqueness of this year’s extreme precipitation-flooding situation,which certainly warrants in-depth exploration,in this article we provide a short view toward a more general hydrometeorological solution to this annual nationwide problem.A“glocal”(global to local)hydrometeorological solution for floods(GHS-F)is considered to be critical for better preparedness,mitigation,and management of different types of significant precipitation-caused flooding,which happen extensively almost every year in many countries such as China,India and the United States.Such a GHS-F model is necessary from both scientific and operational perspectives,with the strength in providing spatially consistent flood definitions and spatially distributed flood risk classification considering the heterogeneity in vulnerability and resilience across the entire domain.Priorities in the development of such a GHS-F are suggested,emphasizing the user’s requirements and needs according to practical experiences with various flood response agencies.  相似文献   

1951—2018年衢州市椪柑采摘期连阴雨天气变化特征     

汪晨  毛程燕  龚理卿  王健疆 《气象与环境学报》2021,37(2):71-76

基于1951—2018年衢州市椪柑采摘期降水量、雨日、日照时数、相对湿度等逐日气象资料,应用统计分析和小波分析方法,分析椪柑采摘期连阴雨天气变化特征及其大气环流背景。结果表明：1951—2018年衢州椪柑采摘期连阴雨日数、次数和强度呈略微增加趋势、滑动3 d无雨次数呈减少趋势;滑动3 d无雨次数存在明显的5 a、7 a和15 a左右的年际和年代际周期变化规律,并且均呈现缩短趋势;椪柑采摘期连阴雨较强年亚欧地区呈两高一低的径向型环流,强冷空气南下活动较频繁、东移缓慢,偏南暖湿气流活跃,致使冷暖空气在中国长江中下游地区长时间交汇,导致连阴雨天气。  相似文献   

秋行夏令:2021年10月初北方致灾性持续暴雨及水汽极端性分析          下载免费PDF全文

车少静  李想  丁婷  高辉 《大气科学学报》2021,44(6):825-834

2021年10月3—6日,我国北方地区经历了历史罕见的持续性极端强降水过程,暴雨中心稳定维持在陕西中部、山西、京津冀、辽宁等地南部和山东北部,给上述地区造成了巨大的经济损失和严重的人员伤亡。基于台站观测降水、NCEP/NCAR和ERA5再分析资料诊断了本次降水过程的极端性。结果表明,本次暴雨过程无论是降水强度、持续时长还是经向水汽输送均表现出典型北方夏季暴雨和大气环流配置特征。上述五省二市区域平均的过程累计雨量强度远远超过秋季其他暴雨个例,即使在夏季也位列第二。本次过程的极端性与强降水中心稳定在上述地区密切相关。上述五省二市区域平均降水连续4日均超过15 mm,这在秋季历史上从未出现过。除过程的极端性强外,9月山西等地降水异常偏多对10月初秋涝也起到了叠加作用。本次秋涝对应的大气环流呈现出典型的北方夏季主雨季环流型,表现为西太平洋副热带高压（副高）偏西偏北,副高西侧的经向水汽输送异常强盛,同时10月4—6日北方地区发生一次强冷空气过程,冷暖气流交汇在上述地区。水汽收支计算表明,本次过程的经向水汽输送强度为秋季历史之最,甚至超过了盛夏时期北方大部分暴雨过程水汽输送强度。上述分析结果表明,即使在仲秋时节亦可产生有利于北方极端持续暴雨的环流形势和水汽输送,并导致秋涝发生。  相似文献   

关于复合型极端事件的新认识和启示          下载免费PDF全文

余荣  翟盘茂 《大气科学学报》2021,44(5):645-649

近年来,极端天气气候事件频繁发生,且常常表现为多种事件交织形成的复合型极端事件。为了更好地认识复合型极端事件,IPCC AR6基于现有的新证据评估了复合型极端事件的最新研究成果,并取得一些新认识：扩展了有关复合型极端事件的定义,重点围绕高温干旱复合型极端事件、复合洪水和野火,评估了复合型极端事件的变化特征,探讨了复合型极端事件多因子之间的依赖性,对人类活动的影响进行了归因分析并给出了未来可能的变化。这些评估结果丰富了对复合型极端事件的基本认识。但根据现有的评估可以发现,目前在复合型极端事件发生发展机理认识方面还存在不足;同时,未来仍需进一步完善跨学科跨部门跨区域研究,加强对复合型极端事件形成机理、预估及其对生态系统,经济社会影响风险的评估,提高对区域气候变化的适应能力。  相似文献   

Rainfall flood hazard at nuclear power plants in India     

Pramod Kumar Sharma 《Georisk: Assessment and Management of Risk for Engineered Systems and Geohazards》2018,12(3):218-233

Flood hazard evaluation is an important input for Nuclear Power Plants external events safety studies. In the present study, flood hazard at various nuclear sites in India due to rainfall has been evaluated. Hazard estimation is a statistical procedure by which rainfall intensity versus occurrence frequency is estimated from historical records of rainfall data and extrapolated with asymptotic extreme value distribution. Rainfall data needed for flood hazard assessment are daily annual maximum rainfall (24?h data). The observed data points have been fitted using Gumbel, power law and exponential distribution, and return period has been estimated. To study the stationarity of rainfall data, a moving window estimate of the parameters has been performed. The rainfall pattern is stationary in both coastal and inland regions over the period of observation. The coastal regions show intense rainfall and higher variability than inland regions. Based on the plant layout, catchment area and drainage capacity, the prototype fast breeder reactor (PFBR) site is unlikely to be flooded.  相似文献   

气候变化情景下澜沧江流域极端洪水事件研究   总被引：1，自引：0，他引：1  

王书霞  张利平  李意  佘敦先 《气候变化研究进展》2019,15(1):23-32

以澜沧江流域为研究对象,基于ISIMIP2b协议中提供的GFDL-ESM2M、HadGEM2-ES、IPSL-CM5A-LR、MIROC5这4种全球气候模式,通过4种模式的输出数据耦合VIC模型,分析4种模式在历史时期（1961—2005年)对洪峰洪量极值(年最大洪峰流量、3 d最大洪量)、极端洪水的模拟能力,比较RCR2.6和RCP6.0两种情景下未来时期（2021—2050年)年均径流量较基准期（1971—2000年)的变化情况,并结合P-III型分布曲线预估了澜沧江流域在两种情景下未来时期极端洪水的强度变化情况。结果表明：VIC模型在该流域能够较好地模拟极端洪水;HadGEM2-ES和MIROC5两种气候模式的输出数据在澜沧江流域有较好的径流模拟适用性;在RCP2.6情景下,澜沧江流域未来时期年均径流量没有明显变化,可能会有略微的增加,而在RCP6.0情景下,未来时期年均径流量有较大可能增加;澜沧江流域未来时期极端洪水较基准期,在RCP2.6情景下无明显变化,而在RCP6.0情景下,洪峰、洪量增加的可能性较大,极端洪水频率和强度也较大可能增加。  相似文献