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Timely and accurate information about the extent of floodwater is critical for emergency planning and disaster management efforts. Despite the advances in computational resources and in the field of remote sensing, there is a clear gap that restricts the disaster community from leveraging the technological resources in real time, which impedes on-ground response efforts. To bridge this gap, this paper makes two contributions. First, the paper presents a new web application, the Global Flood Mapper (GFM) that allows the user to generate flood maps quickly and without getting into technical intricacies. To derive the flood extent from Sentinel-1 satellite data, the pre-flood collection is considered as base and anomaly cells in the during-flood image(s) are identified using Z-Score values. Second, it advances an existing flood mapping method to (a) Map the peak of the floods by combining ascending and descending scenes when necessary, and (b) Check for false positives in hilly terrains by adding slope and elevation mask parameters. By comparing our results with Sentinel-2 MSI derived flood maps and field photographs, we show that the GFM can generate flood maps with precision. The GFM can be used to map and download the extent of multiple flood events of an area as vector data (.kml format), which can be a critical input for flood modeling and risk and impact assessments. The GFM shall enable first responders and practitioners across the globe to overcome technical barriers and lack of computational resources to map the extent of inundation during and after floods. [ABSTRACT FROM AUTHOR]

This paper presents a methodology for estimating coastal flood and inundation risk using passive modeling in four coastal urban areas in India. The methodology has been developed by identifying the latest and publicly available datasets, open-source software, and easily adaptable methodology to estimate coastal flood risk: Mumbai, Chennai, Kochi, and Thiruvananthapuram. The highest projections of combined SLR, tide and surge levels from the GTSMip dataset was used for each of the study areas to model the flood risk for the period 2023–2027. The method has been successful in generating subsidence forecasts for regions where GNSS measurements are not available, resulting in better modeling of coastal flooding risk. Further, including land use as a dampening effect for flood water reduced the risk of overestimation while using bathtub models. The analysis showed that Mumbai had a significantly higher percentage of vulnerable regions than the other three cities. The method can be considered a first step in realistically estimating the coastal flood risks and providing valuable insights for policymakers. [ABSTRACT FROM AUTHOR]

The present paper investigates the impact of future scenarios for the past two storms (namely, Vardah and Madi). These two storms had a different intensity over Bay of Bengal, India. The recent study in this region shows that the influence of these Tropical Cyclones (TC) may be severe in future climatic conditions. Different future Representative concentration pathways (RCP) scenarios are investigated in this study. The combined sea level rise (SLR) and high wind intensity in future scenarios has been investigated in the present study for their influence on maximum water level (MWL), wave climate and coastal inundations. The coupled surge and wave models are used to analyze the influence of SLR and wind intensity for different RCPs. The variations of MWL and inundation extent with increase and decrease in wind increment for different RCPs of the TC's were reported. Overall, for the Far Future RCP 8.5 scenario, the relative percentage of difference (compared to the current scenario) in MWL has increased by 135% for TC Vardah and 180% for TC Madi. Further, the flood area for TC's Vardah and Madi will increase by 70% and 95% compared to the current scenario. Finally, the study reveals that the extreme wind intensity of the TC's in future scenarios plays a significant contribution of up to 50% in coastal inundations. [ABSTRACT FROM AUTHOR]

Climate change is expected to exacerbate the extremes in the climate variables. Being prone to harsh climate impacts, it is very crucial to study extreme rainfall-induced flooding for short durations over regions that are rapidly growing. One way to study the extremes is by the application of the Intensity-Duration-Frequency (IDF) curves. The annual maximum rainfall intensity (AMRI) characteristics are often used to construct these IDF curves that are being used in several infrastructure designs for urban areas. Thus, there is a need to obtain high temporal and spatial resolution rainfall information. Many urban areas of developing countries lack long records of short-duration rainfall. The shortest duration obtained is normally at a daily scale/24 h. Thus, it is very crucial to find a methodology to construct IDF curves for short-duration rainfall (sub-daily) for these urban areas. Vietnam is a developing country with rapidly increasing population as well as urbanization. The fast extension of urban area that does not have adequate preparedness to cope with climate change is certainly a big risk to life and economy. The limitation in studying impacts over many regions of Vietnam is the need for robust and sufficient data, both spatial and temporal. To overcome this limitation, this paper describes constructing IDF curves using 6 hourly rainfall AMRI output from a regional climate model (RCM) that downscaled a global climate model (GCM) output at high spatial and temporal resolutions. The study region is Hanoi, the capital city of Vietnam. The sub-daily IDF curves for current and future climate for Hanoi were constructed from 1 to 24 h based on the simple scaling approach. The findings indicate that it is likely that Hanoi might experience more flooding conditions in the future with the AMRI increasing between 34 and 48% for all return periods from 10 to 200 years. The methodology adopted in this paper is suitable for similar ungauged areas elsewhere and will provide useful information in devising adequate planning strategies for drainage designs. [ABSTRACT FROM AUTHOR]

Enhanced ways to cope with climate change and environmental change are being made at various levels across the world. In the southern African region, despite the regions' potential for economic growth, several disasters associated with climate stresses (particularly evidence made for repeated floods and droughts) can retard economic growth, development and livelihood security. In this paper, disaster inventories are argued to be useful ways of revealing nuanced analyses of extreme climate events and other challenges such as the spatial-temporal distribution of events and their impacts, particularly for vulnerable people groups. Despite repeated calls for vigilance about current and future climate variations and environmental change impacts, there are few detailed regional and country-specific inventories of disasters and records of subsequent humanitarian responses that record both impacts and possible implications of disaster events in the region. This paper draws together those data that do exist and offers a review of the occurrences, impacts and past responses to humanitarian crises in the region (for 14 countries over the period of 2000-2012). From this research a number of critical areas are profiled: first, the convergence of compound and complex shocks that occur simultaneously and/or sequentially is compounding disaster risks-including those associated with climate challenges. A review of international and regional UN agency, NGO and governmental reports all illustrates the need to articulate between internationally significant, 'signature' events and smaller, sub-national events with a higher recurrence interval that may be just as damaging to local communities. Second, the reach of disaster impacts is changing with the region becoming increasingly more mobile in terms of the movement patterns of people within countries and across borders, which brings with it new compound and complex threats such as cholera and measles outbreaks. Third, the nature of the changing disaster profile is placing strain on countries and the region. Sub-national disaster response due to personnel capacity limitations, at the national and municipal levels, is unable to effectively respond to and reduce risks associated with various shocks. In the paper, by providing an inventory of disasters and humanitarian responses in the southern African region, we point to the changing regional and national dimensions of the region's disaster risk profile that, we suggest, will require a variety of responses. [ABSTRACT FROM AUTHOR]

Climate change leads to sea level rise worldwide, as well as increases in the intensity and frequency of tropical cyclones (TCs). Storm surge induced by TC's, together with spring tides, threatens to cause failure of flood defenses, resulting in massive flooding in low-lying coastal areas. However, limited research has been done on the combined effects of the increasing intensity of TCs and sea level rise on the characteristics of coastal flooding due to the failure of sea dikes. This paper investigates the spatial variation of coastal flooding due to the failure of sea dikes subject to past and future TC climatology and sea level rise, via a case study of a low-lying deltaic city- Shanghai, China. Using a hydrodynamic model and a spectral wave model, storm tide and wave parameters were calculated as input for an empirical model of overtopping discharge rate. The results show that the change of storm climatology together with relative sea level rise (RSLR) largely exacerbates the coastal hazard for Shanghai in the future, in which RSLR is likely to have a larger effect than the TC climatology change on future coastal flooding in Shanghai. In addition, the coastal flood hazard will increase to a large extent in terms of the flood water volume for each corresponding given return period. The approach developed in this paper can also be utilized to investigate future flood risk for other low-lying coastal regions. [ABSTRACT FROM AUTHOR]

Modern flood risk management strategies have evolved from flood resistance to a holistic approach incorporating prevention, protection and preparedness with the aim of reducing the likelihood and/or impact of flooding. This evolution has been driven by a trend of increasingly damaging and frequent flood events due to climate change. Populations at risk are required to be an active participant within modern flood risk management plans, resulting in management plan effectiveness being partially dependent on the relevant population's flood risk perception. Thus, understanding how at-risk populations perceive their own flood risk, and how this compares to the reality of the situation, is a significant component of flood risk management. This paper compares subjective risk perception to an objective measure of risk within a specific case study area, where 305 residents were surveyed on their perception of flood risk. As part of the survey, respondents were asked to delineate the areas of the study area that they perceived would be at risk of inundation during a severe flood event. Using spatial statistical indicators, including Fuzzy Kappa comparison, it was possible to quantify the divergence between subjective and objective measures of risk extent, enabling an assessment of the 'correctness' of subjective perceived risk. This novel approach identified significant deviations between risk perception and objective risk measures at an individual level. The paper concludes by considering potential policy implications. [ABSTRACT FROM AUTHOR]

Hydrological extreme events pose an imminent risk to society and economics. In this paper, various aspects of hydrological hazards in Russia are analysed at different scales of risk assessment. It is shown that the number of hydrological and meteorological hazards in Russia has been growing every year. The frequency of economic losses associated with extreme low flow in this century has increased by factor five compared to the last decade of the previous century. With regard to floods, an interesting spatial patter can be observed. On the one hand, the number of floods in the Asian part of the country has increased, whereas on the other hand, the number and intensity of floods in estuarine areas in the European part of Russia have significantly reduced since the middle of the twentieth century, especially in the 2000s. This decrease can be attributed to runoff flooding in the mouths of regulated rivers, with an effective system of flood and ice jam protection. The analysis shows that there is an 8-12-year periodicity in the number of flood occurrences and that flood surges have intensified over the last 110 years, especially on the European territory of Russia. An integrated index that accounts for flood hazards and socio-economic vulnerability was calculated for each region of Russia. A classification of flood risk was also developed, taking into account more than 20 hydrological and social-economic characteristics. Based on these characteristics, hazard and vulnerability maps for entire Russia were generated which can be used for water management and the development of future water resources plans. [ABSTRACT FROM AUTHOR]

Critical infrastructures are essential for the society and economy. In recent years, climate change has been identified as an urgent and growing threat to critical infrastructures, and many studies have been conducted to assess the vulnerability of critical infrastructures to climate change. However, despite these research efforts, the vulnerability of critical infrastructures is often vaguely defined and inconsistently studied in the literature. This paper proposes a framework to analyze critical infrastructure's vulnerability to climate change based on the traditional vulnerability/sustainability framework and hazard-of-place model of vulnerability. The vulnerability assessment of emergency services to sea level rise and storm surge in Collier County, Florida, is taken as an example to validate the proposed framework. Flood simulation, comparisons of storm surge models, spatial analysis, and network-based service area analysis are conducted to assess the vulnerability of fire stations in the case study area. The vulnerability assessment identifies the predominant hazard risk and the exposed infrastructures, analyzes the sensitivity of serviceability, and evaluates the effectiveness of potential adaptive capacity. The results show that the fire stations in the case study area are more vulnerable to the potential landfall and changes in hurricane and tropical cyclone patterns compared to the flooding caused directly by sea level rise. It indicates that the lack of consideration of potential landfall and changes in storms could greatly underestimate the vulnerability to climate change, especially in coastal areas with limited historical tidal data. The analysis also illustrates the current floodplain management that focuses primarily on the 100-year flood may not be a sufficient standard for all regions given the potential changes in frequency and magnitude of climate-related hazards. Finally, it confirms that disaster risk management strategies could also contribute to climate change adaptation. The weak linkages between existing climate change adaptation and disaster risk management need to be strengthened. The proposed concept and framework could be generalized and expanded to other critical infrastructures, regions, and climate-related hazards. [ABSTRACT FROM AUTHOR]

This paper utilizes a multi-level governance framework to explain how and at what scale climate adaptation, exemplified by flood risk management, was governed in the medium-scale city of Saint Louis, Senegal. It explores how this policy sector worked toward a 'resilient city' pointing to gaps between governance as prescribed and as practiced. The paper suggests that strong coordination of climate change adaptation and flood risk management should take place at city level, reflecting the 'place-based' character of these policy sectors. However, adaptation cannot be addressed successfully at any single geographic scale or by any one category of actor. Effective collaboration across politico-administrative boundaries at multiple scales is required in order to address tensions between competing policy agendas and tackle socio-spatial inequality and vulnerability. We found that public officials at the city and regional state level encouraged some degree of citizen participation in planning and input into adaptation. However, despite emerging networks for city-level coordination and capacity to adapt to flood risks among local residents, there were limitations in how higher-level government and institutions supported the lower levels in vertical and horizontal coordination. In particular, services and investments within poor and vulnerable settlements were lacking. This undermined the capability of municipal staff for local engagement and for diverse groups of residents to become really effective partners with the government in coproducing services required to enhance resilience. More so, it limited opportunities to bring local actions to scale-beyond the city boundaries and toward transitional adaptation and transformation. [ABSTRACT FROM AUTHOR]

An introduction is presented in which the editor discusses various reports within the issue on topics including the impact of urban flooding, climate change adaptation and the performance of the adaptive delta management (ADM) approach in flood risk strategies.

In the companion paper, Seidou et al. (, submitted) have shown that when adequate meteorological data are available to calibrate rainfall-runoff models, using a non-stationary GEV model with the simulated flows can provide a better description of flood peaks distributions than directly using the simulated peaks. Their methodology is extended in this paper to improve future flood peaks simulation under a changing climate. In this case, the rainfall-runoff model is forced with the downscaled outputs of the Canadian General Circulation Model CGCM3. Special attention is paid to the statistical downscaling of precipitations, as the choice of the transfer function has a significant influence on the performance of non-stationary GEV model. Stepwise regression was initially used to describe precipitation occurrence and intensity, but the patterns of the simulated hydrographs were found to be unsatisfactory. After precipitation occurrence model was successfully replaced with an ensemble of regression trees, the non-stationary GEV model was shown to provide a better description of flood peaks in the observation period. The non-stationary GEV model shows that exceedance probabilities on the Kemptville Creek will gradually rise up to 34% above current levels in 2100 for a 20-year service life. [ABSTRACT FROM AUTHOR]

Flood risk assessments are an objective and quantitative basis for implementing harmonized flood mitigation policies at the basin scale. However, the generated results are subject to different sources of uncertainty arising from underlying assumptions, data availability and the random nature of the phenomenon. These sources of uncertainty are likely to bias conclusions because they are irregularly distributed in space. Therefore, this paper addresses the question of the influence of local features on the expected annual damage in different municipalities. Based on results generated in the frame of a transnational flood risk assessment project for the river Meuse (Western Europe) taking climate change into account, the paper presents an analysis of the relative contributions of different sources of uncertainty within one single administrative region (the Walloon region in Belgium, i.e., a river reach of approximately 150 km). The main sources of uncertainty are not only found to vary both from one municipality to the other and in time, but also to induce opposite effects on the computed damage. Nevertheless, practical conclusions for policy makers can still be drawn. [ABSTRACT FROM AUTHOR]

The last few years have seen enormous damage and lossof life from climate and weather phenomena. The mostdamaging events have included the severe 1997/98 ElNiño (with its near-global impacts), HurricaneMitch, and floods in China in mid-1998. What have welearnt regarding the causes, variability, andpredictability, of these phenomena? Can we predict theoccurrence of these extreme events, and therebymitigate their damage? This paper reviews what we havelearnt in the last decade or so regarding thepredictability of these climate and weather extremes.The view starts with the largest (El Niño) scales,and works towards the scale of individualthunderstorms. It focuses on the practical outcomes ofour improved knowledge with regard to decreasing theimpact of natural disasters, rather than describing indetail the scientific knowledge underlying theseoutcomes. The paper concludes with a discussion ofsome of the factors that still restrict our ability tomitigate the deleterious effects of atmospheric andclimatic hazards. [ABSTRACT FROM AUTHOR]

Sea level rise (SLR) and storm surge have significant impacts on tourism properties and activities in the low-lying coastal region. Coastal tourism in Zhejiang Province, China, is physically and socioeconomically susceptible to the flood risk posed by accelerated SLR and intensified storm surge. In this paper, within a scenario design of SLR and storm surge, a GIS-based dataset of major coastal tourist attractions in coastal Zhejiang is created to assess their potential flood risk by using a simple inundation model and a risk matrix. It is estimated that only two resorts would be directly flooded by a SLR of 1-2 m, but extensive inundation of coastal tourism communities may occur during low-frequency surges, especially after adding predicted 1-m SLR. The risk assessment further shows that a majority of the exposed sites is subject to moderate and low risk at current state but would be at higher (moderate and high)-risk categories in the future. In the long term, a combination of adaption measures is presented for policy-makers and other stakeholders for sustainable flood risk management in coastal tourism destinations. [ABSTRACT FROM AUTHOR]

There is a growing concern over the unprecedented shifts in seasonality and extreme rainfall over the last century across the globe due to climate change. However, there is still a lack of basin-scale study in documenting trend, changes, and variation across Peninsular Malaysia and its relation with flood occurrence. Therefore, Johor River basin (JRB) which plays a pivotal role in the country's development was selected as a case study by evaluating 24 rainfall stations for homogeneity over the period 1970–2015 and followed by the analysis of rainfall seasonality and extreme rainfall trend. Mann–Kendall trend test was applied to show the area within JRB that is subjected to change at 95% significance level. Even though 75% of the stations had strong auto-correlation in the time series due to large-scale climate influence, the imputed rainfall stations showed no potential discontinuity with t-test statistics between 0.87 and 0.90 and R2 between 0.995 and 0.999 for the double mass curve of the yearly rainfall time series. The constructed PDF showed the restoration of the normal distribution of the rainfall data with higher peak as the missingness of the high-intensity rainfall has been restored. After that, a homogeneity test was conducted for annual and seasonal rainfall using a hybrid of Standard Normal Homogeneity test, Pettit test, Buishand Range test, and Von Neumann ratio test. The results showed that for the annual series, 43% of the total stations were found to be 'useful', but more 'useful' stations based on the seasonal data, with 67% and 52% of the total stations for NE and SW monsoons, respectively. As no anthropogenic effect can be deduced, the presence of inhomogeneity in some stations is associated with the influence of high climate variability. Although non-significant change was observed, the seasonality index (SI) showed that the annual rainfall regime in JRB is mainly classified as 'rather seasonal with a short drier season' (SI range from 0.39 to 0.47). Comparatively, the rainfall regime during the drier SW monsoon is more irregular (SI range from 0.67 to 0.72) than the wetter NE monsoon (SI range from 0.57 to 0.68). Spatially, increasing SI was observed in the downstream area indicating increasing occurrence of extreme rainfall over a shorter period. For trend analysis, RClimDex was utilised to compute eleven extreme rainfall indices as recommended by ETCCDI, consisting of frequency and intensity extreme rainfall indices. Generally, the results showed that increasing extreme rainfall in the form of frequency indices is more prominent throughout JRB particularly at the end of the NE monsoon. During the NE monsoon, frequency index of R10 showed a significant increasing trend at thirteen stations. Meanwhile, R20 and R25 showed increasing trend at five stations, mainly in the downstream and at the west of the basin. During the SW monsoon, R10 showed a significant increasing trend at six stations, but R20 and R25 showed a significant decreasing trend at two and one station, respectively. Based on the past flood record, increasing trend of R10, R20, R25, and CWD during the NE monsoon across flood prone area in Sayong river, Kota Tinggi town and downstream urbanised area is expected to worsen the flood conditions, which required improved flood mitigation and adaptation strategy. [ABSTRACT FROM AUTHOR]

Similarly to other modes of transport, inland waterway transport has to deal with weather events, affecting navigation conditions and the infrastructure on inland waterways. Most significant extreme weather events result from high precipitation, droughts and temperatures below zero degrees Celsius. Heavy rainfall, in particular in association with snow melt, may lead to floods resulting in suspension of navigation and causing damage to the inland waterway infrastructure as well as the property and health of human beings living in areas exposed to flooding. Long periods of drought may lead to reduced discharge and low water levels, limiting the cargo-carrying capacity of vessels and increasing the specific costs of transportation. Temperatures below zero degrees Celsius over a longer period may cause the appearance of ice on waterways, leading to suspension of navigation and possible damage to infrastructure, for example, buoys. Neither extreme weather events as well as climate change are new phenomena nor is their general occurrence expected to change suddenly. However, due to climate change, extreme weather events may change positively or adversely in severity and frequency of occurrence, depending on the respective weather event and the location of its occurrence. This paper gives an overview of the impact of extreme weather events on inland waterway transport in Europe, focussed on the Rhine-Main-Danube corridor, followed by a discussion on how climate change will change these events and their impacts. [ABSTRACT FROM AUTHOR]

A Kuznets curve is the graphical representation of Simon Kuznets' hypothesis that as a country develops, there is a natural cycle of economic inequality driven by market forces, which at first increase inequality and then decrease it after a certain average income is attained. The concept has been applied to environmental studies hypothesizing that the relationship between per capita income and the use of natural resources and/or the emission of wastes has an inverted-U shape. This paper presents a holistic study aimed at validating the applicability of the Kuznets curve to flood disaster. The focus is China and Japan. Both countries are prone to flooding and have experienced great economic growth. Data analysis detected the turning points of annual flood fatality in both countries, and the change in annual flood fatality with economic growth in both countries was found to match the Kuznets curve. However, the variation pattern of annual flood-caused economic loss was different between China and Japan. The difference may be partially attributed to the difference in residential characteristics between the two countries. Besides, it was found that climate change affected the flood-caused economic loss in Japan over recent decades. Furthermore, the variations in annual flood fatality and economic loss in the largest city of China were also analyzed. [ABSTRACT FROM AUTHOR]

The northern coasts of the Gulf of Mexico (GoM) are highly vulnerable to the direct threats of climate change, such as hurricane-induced storm surge, and such risks are exacerbated by land subsidence and global sea-level rise. This paper presents an application of a coastal storm surge model to study the coastal inundation process induced by tide and storm surge, and its response to the effects of land subsidence and sea-level rise in the northern Gulf coast. The unstructured-grid finite-volume coastal ocean model was used to simulate tides and hurricane-induced storm surges in the GoM. Simulated distributions of co-amplitude and co-phase lines for semi-diurnal and diurnal tides are in good agreement with previous modeling studies. The storm surges induced by four historical hurricanes (Rita, Katrina, Ivan, and Dolly) were simulated and compared to observed water levels at National Oceanic and Atmospheric Administration tide stations. Effects of coastal subsidence and future global sea-level rise on coastal inundation in the Louisiana coast were evaluated using a 'change of inundation depth' parameter through sensitivity simulations that were based on a projected future subsidence scenario and 1-m global sea-level rise by the end of the century. Model results suggested that hurricane-induced storm surge height and coastal inundation could be exacerbated by future global sea-level rise and subsidence, and that responses of storm surge and coastal inundation to the effects of sea-level rise and subsidence are highly nonlinear and vary on temporal and spatial scales. [ABSTRACT FROM AUTHOR]

This paper reports exploratory research conducted in a flood-impacted rural Australian town to identify the factors which residents perceived as supporting community resilience to disaster. There is a gap in this research area centred in the Australian disaster context. Since Australia is predicted to be highly impacted by the effects of climate change in the form of an increased incidence of flooding, an urgent need exists to examine the factors that confer resilience to disaster-impacted localities to inform suitable disaster mitigation and adaptation policies for the future. Because of the complexity of community resilience and its interrelationship with individual resilience, a multi-method approach was used: a demographic study to assess community stability and functioning before and after the flood disaster, focus group interviews to obtain from community members their views on what supported them and their community resilience and a survey to generalise the interview findings. Our operating hypothesis was that individuals remaining in the town post-flood were likely to be resilient to the flood disaster. The demographic study results pointed to a resilient community after the floods as they reflected stability in population numbers and socio-economic indicators. The interviews and survey showed that individual resilience was promoted by social connectedness and a sense of place, a factor that was also negatively linked to the desire to relocate from the community. The use of structural equation modelling of our results provided verification of prior research findings about the role of sense of place in supporting individuals' resilience. Results are discussed in the context of future climate change adaptation policy. [ABSTRACT FROM AUTHOR]

Taiwan suffers from losses of economic property and human lives caused by flooding almost every year. Flooding is an inevitable, reoccurring, and the most damaging disaster in Taiwan since Taiwan is located in the most active tropic cyclone formation region of the Western Pacific. Flooding problem is further worse in land subsidence areas along southwestern coast of Taiwan due to groundwater overdraft. Increasing number of people is threatened with floods owing to climate change since it would induce sea level rise and intensify extreme rainfall. Assessments of flooding vulnerability depend not only on flooding severity, possible damage of assets exposed to floods should also be simultaneously considered. This paper aims at exploring how climate change might impact the flooding vulnerability of lowland areas in Taiwan. A flooding vulnerability evaluation scheme is proposed in this study which incorporates flooding severity (the maximum inundation depth determined by a two-dimensional model) and potential economic losses for various land uses. Effects of climate change on flooding vulnerability focus on alterations of rainfall depth for various recurrence intervals. The flood-prone Yunlin coastal area, located in southwestern Taiwan, is chosen to illustrate the proposed methodology. The results reveal that reducing flooding vulnerability can be achieved by either reducing flooding severity (implementation of flood-mitigation measures) or decreasing assets exposed to floods (suspension of land uses for flood-detention purpose). Performance of currently implemented flood-mitigation measures is insufficient to reduce flooding vulnerability when facing with climate change. However, the scenario suggested in this study to sustain room for floods efficiently reduces flooding vulnerability in both without- and with climate change situations. The suggestions provided in this study could support decision processes and help easing flooding problems of lowland management in Taiwan under climate change. [ABSTRACT FROM AUTHOR]

The failure of the Tous dam in 1982 caused one of the most important socio-natural disasters in Spain during the twentieth century. That event triggered a paradigm change in the way disaster risks were perceived and managed, not only locally, but also at multiple levels of governance. Fifteen interviews with relevant stakeholders, content analysis of scientific literature, and review of historical and media accounts indicate that the collapse of the Tous dam had the two major effects. First, it prompted a process of institutional development, which led to the growth, and increase in complexity of the organizations involved both in vertical and horizontal communication of disaster risk reduction. Second, actions taken and experiences gained in dealing with disaster risk reduction in the Tous area were used as a benchmark to develop new strategies, as well as new mechanisms for communication and planning in other territories and other risk domains in Spain. This paper also identified the three main stages in the evolution of disaster risk reduction planning in the area: (1) After the collapse of the Tous dam, disaster risk reduction strategies in Spain focused on improving preparedness in order to reduce short-term risks. (2) Disaster management in the 1990s was strongly influenced by international initiatives, which emphasized the contextualization of risk and the importance in long-term disaster risk reduction measures such as land-use planning. (3) The European Water Framework Directive (2000) and, more recently, the Floods Directive (2007) are exerting a strong influence on the development of a new Spanish flood policy that focuses on preventive measures. However, this process is far from complete and many issues still remain unresolved: dealing with different domains of risk action, integrating concepts of ecological resilience and climate change, and promoting public awareness and effective participation. [ABSTRACT FROM AUTHOR]

Coastal inundation from hurricane storm surges causes catastrophic damage to lives and property, as evidenced by recent hurricanes including Katrina and Wilma in 2005 and Ike in 2008. Changes in hurricane activity and sea level due to a warming climate, together with growing coastal population, are expected to increase the potential for loss of property and lives. Current inundation hazard maps: Base Flood Elevation maps and Maximum of Maximums are computationally expensive to create in order to fully represent the hurricane climatology, and do not account for climate change. This paper evaluates the coastal inundation hazard in Southwest Florida for present and future climates, using a high resolution storm surge modeling system, CH3D-SSMS, and an optimal storm ensemble with multivariate interpolation, while accounting for climate change. Storm surges associated with the optimal storms are simulated with CH3D-SSMS and the results are used to obtain the response to any storm via interpolation, allowing accurate representation of the hurricane climatology and efficient generation of hazard maps. Incorporating the impact of anticipated climate change on hurricane and sea level, the inundation maps for future climate scenarios are made and affected people and property estimated. The future climate scenarios produce little change to coastal inundation, due likely to the reduction in hurricane frequency, except when extreme sea level rise is included. Calculated coastal inundation due to sea level rise without using a coastal surge model is also determined and shown to significantly overestimate the inundation due to neglect of land dissipation. [ABSTRACT FROM AUTHOR]

In August 2001, the worst flash flooding event of the Caspian Sea regions in over two centuries claimed over 300 lives after a weekend of heavy rainfall and brought about a devastating disaster in the Mother-Soo catchment, province of Golestan, Iran. As a result of this event, a series of site investigation were carried out to identify the pertinent factors that led to a flood of this magnitude. This paper identifies the fundamental causes of the frequent floods and debris flow occurrence in the area prone to flooding and analyzes the main runoff mechanism of these events. The maximum observed 24-h rainfall depths and maximum peak discharges at the existing gauges were compared with the depths of rainfall and the peak values corresponding to the August 2001 flood respectively. For the majority of the rain gauges, the rainfall depth exceeded those of historical recorded events. In Golestan dam, an increase of 7.5 times the maximum value observed in the past 20 years was noted. The flood height was 10-15 m while passing through the middle subcatchment area of Golestan National Park. The preliminary evaluation indicates the existence of bare soil in the catchment, movable material, steep slopes, high rainfall intensity, deterioration of pasture and forest land, and inappropriate agriculture and development practices as well as climate change were the main factors for the occurrence and the extent of the August 2001 disaster. Finally, due to the likelihood of flooding and debris flow events in future, some countermeasures are proposed. [ABSTRACT FROM AUTHOR]

There is an increasing concern that the current management practices for many coastal regions are unsustainable. Very few countries have planned to deal with the exacerbation of environmental decline in the face of sea level rise. It is therefore necessary to assess socioeconomic and environmental impacts of sea level rises to better understand the vulnerability of coastal zones, as part of devising adaptive and integrated management principles. This paper presents a systematic approach by which relevant stakeholders can be actively engaged in prioritising flood impact issues and deriving information for quantification of impacts for adaptation measures and demonstrates the approach through implementation in the Gippsland coastal region. As outcomes of the project, we have identified key issues of concern for this region for flood impacts and constructed synthetic response functions for quantification of impacts of floods on some of the key issues in the region. The analysis also showed that stakeholders consider that some of the issues are not likely to be significantly affected by floods and thus may not require adaptation measures. The analysis did not provide high agreement on some issues. Different approaches are required to assess the importance of these issues and to establish impact response functions for them. [ABSTRACT FROM AUTHOR]

Under the background of global climate change and rapid development of urbanization, urban extreme occurs more frequently. In consideration of the existing problems in the emergency management decision-making of urban rainstorm and flood disasters in China, this study put forward the decision-making method of urban rainstorm and flood disaster emergency management based on similar cases analysis method. Based on the evolution process of urban waterlogging disaster, the problem attribute system of urban rainstorm and flood disasters was established. The case-based reasoning (CBR) method was used to calculate the global similarity to determine the best historical case. The case-based decision theory (CBDT) method was used to calculate the comprehensive utility value of alternative cases to determine the optimal alternative cases. The empirical analysis was took in Xi'an city, one of the national center cities of China. Results show that the CBR method was used to obtain the highest similarity of historical case P3, which is 0.481. The CBDT method was used to calculate the high similarity of historical cases P3 and P4 to form the similar case set, with the similarity of 0.820 and 0.851, respectively. Combined with the event development, the comprehensive utility values were calculated. When the decision-maker pays the same attention to the emergency effect and response cost, the comprehensive utility value of P3 and P4 is 0.922 and 0.900, respectively, and P3 is the best reference scheme. By comparison, the latter is more suitable. The results can provide scientific basis for emergency management of urban rainstorm and flood disasters. [ABSTRACT FROM AUTHOR]

In the context of climate change and urbanization, flood becomes one of the most important threats to human life, health, and property. Coastal areas gathering large numbers of population, capital, and industries are vulnerable to suffering from the compound floods caused by hydrological and oceanic processes. The disaster mechanisms of compound floods are more complex, and the consequences are even more serious. Based on the existing research results, this article sorts out the main disaster mechanisms of compound floods in coastal areas and explains the main methods, including using statistical models to study the dependence between flood drivers or joint probability and numerical models to simulate compound flood inundation, and presents the characteristics of different methods. We also discuss the advantages and disadvantages of different models and analyze their uncertainties. Current research seldom considers the rainfall-runoff-storm surge compound flood and the effect of climate change. In addition, there are only a few kinds of literature that integrate statistical models and numerical models to investigate compound flood hazard. Uncertainties in compound flood study methods are also less considered. Future investigation should focus on the characteristics and uncertainties of different models and consider the impact of climate change on compound floods. These will help to fully understand compound floods, research models, and provide effective opinions for flood management in coastal areas. [ABSTRACT FROM AUTHOR]

In the active tectonic setting of Aotearoa/New Zealand, large earthquakes are a relatively frequent occurrence and pose particular threats to infrastructure and society in Westland, on the west coast of South Island. In order to better define the medium- and long-term (annual to decadal) implications of these threats, existing dendrochronological data were supplemented by several hundred tree-ring analyses from 14 hitherto unstudied living tree stands in five catchments; these were combined to compile a regional picture of the location, extent, and timing of major prehistoric reforestation episodes on the floodplains of the area. These episodes correspond well with known dates of large earthquakes in the area (ca. 1400, ca. 1620, 1717 and 1826 AD), and their extents are thus interpreted to reflect the sediment deliveries resulting from coseismic landsliding into mountain valleys, and their reworking by rivers to generate widespread avulsion, aggradation, floodplain inundation and forest death. This regional aggradation picture can underpin anticipation of, and planning for, the medium- to long-term societal impacts of future major West Coast earthquakes. The source location of the next major earthquake in the region is unknown, so any of the Westland floodplains could be affected by extensive, up to metre-scale river aggradation, together with avulsion and flooding, in its aftermath, and these could continue for decades. Re-establishment and maintenance of a functioning economy under these conditions will be challenging because roads, settlements and agriculture are mostly located on the floodplains. The differences in floodplain vegetation between prehistoric and future episodes will affect the rapidity and distribution of aggradation; response and recovery planning will need to consider this, together with the impacts of climate changes on river flows. [ABSTRACT FROM AUTHOR]

Deltas are the promising places with multifarious ecosystems and arable soils along with the ease of water transportation system; hence, a number of important cities are established in or near coastal delta regions. However, due to the geomorphic characteristics, those cities are extremely exposed to hydro-meteorological hazards, especially to riverine and coastal flood. Additionally, climate change, rapid urbanization and subsidence are exacerbating the existing situation and causing monumental loss. Researchers as well as various international organizations like United Nations Inter-Agency Secretariat of the International Strategy for Disaster Reduction have recognized the implications of formulating disaster risk reduction (DRR) plans for coastal delta cities. This demands for the excogitation of adaptation policies and measures in addition to the mitigation efforts to reduce flood risks. In this regard, to support the comprehensive concept development, this study elicits different components of flood risk reduction policies and measures, congenial for coastal delta cities in respect of physical and environmental perspectives. Eleven precedent (model) cities are selected to study their various initiatives for reducing coastal flood risks. Findings show that protecting cities from flooding and reducing exposure to floods are two different but interrelated approaches of DRR. Combinations of structural and non-structural measures are the prerequisites to achieve the goal of effective DRR. [ABSTRACT FROM AUTHOR]

Over the last decade, the Amazon region has been hit by some of the worst floods in history. The floods killed hundreds of people and damaged thousands of homes. However, in southeast Brazil, specifically in the states of Sao Paulo, Rio de Janeiro, and Minas Gerais, a highly significant decreasing rainfall trend has been discovered. The Sao Paulo State drought has had a significant impact on national electrical energy and agricultural productivity. In the last 100 years and 90 years, respectively, 2021 was a record flood in the Amazon region and a record drought in southeast Brazil. According to this study, recent floods in the Amazon and droughts in southeast Brazil, particularly extreme events in 2021, are strongly linked to the changing Hadley cell. [ABSTRACT FROM AUTHOR]

The Upper Yangtze River (above Yichang) in China has constructed the world's largest reservoir group with the Three Gorges Reservoir (TGR) as the core, the operation of these reservoirs and future climate change will no doubt alter the downstream hydrological processes and pose a challenge to the downstream flood design. As Yichang Hydrologic Station is 44 km downstream of TGR, how the design flood at Yichang Station would be impacted in the future by climate and upstream reservoirs has rarely been investigated. In this study, the climate and upstream reservoirs effects on design flood at Yichang Station are evaluated under six future climate and reservoir scenarios (S1, S2, S3, S4, S5 and S6) with different combinations of summer precipitation anomaly (SPA) and reservoir index (RI), in which SPA is obtained from global climate models under the three emission scenarios (SSP1-2.6, SSP2-4.5 and SSP5-8.5) of CMIP6 and RI is calculated under the two reservoir conditions (RI at current level and RI at planning level). The SPA and RI of S1, S2, S3, S4, S5 and S6 are, respectively, substituted into the optimal nonstationary GEV probability model, and the corresponding 1000-year design floods are estimated by using average annual reliability method. Under the same future reservoir condition, the flood peak discharge, 3-day, 7-day, 15-day and 30-day flood volume (denoted as Qm, W3, W7, W15 and W30, respectively) under SSP2-4.5 and SSP5-8.5 are 0.2% ~ 2.5% larger than those under SSP1-2.6. The change rates of Qm, W3, W7, W15 and W30 under six scenarios relative to the stationary design flood values calculated by Changjiang Water Resources Commission range from −11.4% to −23.9%, and the reduction amount of Qm is more than 16,000 m3/s even under SSP5-8.5. Therefore, reservoirs impact on the design flood of Yichang Station is quite prominent. [ABSTRACT FROM AUTHOR]

With climate change, hydro-climatic hazards, such as floods in the Himalayas regions, are expected to worsen, thus likely to overwhelm humans and socioeconomic system. Precisely, the Koshi River basin (KRB) is often impacted by floods over time. However, studies on estimating and predicting floods are still scarce in this basin. This study aims at developing a flood probability map using machine learning algorithms (MLAs): Gaussian process regression (GPR) and support vector machine (SVM) with multiple kernel functions including Pearson VII function kernel (PUK), polynomial, normalized poly kernel, and radial basis kernel function (RBF). Historical flood locations from available (topography, hydrogeology, and environmental) datasets were further considered to build a flood probability model. Two datasets were carefully chosen to measure the feasibility and robustness of MLAs: the training dataset (flood locations between 2010 and 2019) and the testing dataset (flood locations of 2020) with thirteen flood influencing factors. Validation of the MLAs was performed with statistical indices such as the coefficient of determination (r2: 0.546 –.995), mean absolute error (MAE: 0.009 –373), root mean square error (RMSE: 0.051–0.466), relative absolute error (RAE: 1.81–8.55%), and root-relative square error (RRSE: 10.19–91.00%). Results showed that the SVM-Pearson VII kernel (PUK) yielded better prediction than other algorithms. The resultant map from SVM-PUK revealed that 27.99% area with low, 39.91% area with medium, 31.00% with high, and 1.10% area with very high probabilities of flooding in the study area. The flood probability map, derived in this study, could add great value to the effort of flood risk mitigation and planning processes in KRB. [ABSTRACT FROM AUTHOR]

The increasing rate of anthropic activities in flood-prone areas and the effects of climate change are aggravating the dangers posed by floods to people. One of the main reasons for fatality during flood events is walking through floodwaters. Although authorities strongly advise against walking in flood waters, evacuations or the accessing of flooded areas by emergency services might be necessary. This research proposes a novel approach to increasing resilience by retrofitting existing infrastructures to enhance evacuation and access routes by reducing flood hazard rate based on flood and pedestrian characteristics. The methodology was applied to flash floods in two case studies in the UK, namely Boscastle and Borth, highlighting that retrofitting small regions of the existing roads and pathways to reduce flood hazard can enhance people's safety during the evacuation, and hence provides a solution to improve the resilience of the existing environment. [ABSTRACT FROM AUTHOR]

Rapid urbanization has become and will continue to be an inevitable and inescapable phenomenon in the developing world. Unplanned expansion of cities and the impacts of climate change increase risks and pose challenges to sustainable development. Urban flooding is a hazard that is attributed to an increase in built-up area and extreme weather events. Despite this, little has been done to understand the impact of urbanization and climate change, particularly in the big cities of Africa. This research integrated GIS, remote sensing, and statistical analysis to study past and future urban development patterns, rainfall trends, and their impact on urban flooding risk in Addis Ababa, Ethiopia. Future urbanization scenarios were developed using an integrated artificial neural network–Markov model in the IDRISI Selva 17.0 software, while a soil conservation service–curve number model and a Mann–Kendell test were employed to study direct runoff and trends in precipitation. The methodology and workflow were designed to address limitations of conducting empirical study, especially for developing countries, caused by the lack of detailed data on past and present conditions like land-use maps, networks of meteorological stations, and soil-related datasets such as soil texture and moisture. The results indicate that rapid urbanization is the major cause of flooding in Addis Ababa, spiking from 80.1 km2 in 1984 to 287.9 km2 in 2020 and expected to increase to 367.1 km2 in 2030 under a business-as-usual scenario. The fast urbanization has increased the number of flooding susceptible woredas (smallest administrative units) to a direct runoff depth of 25 mm from 40 in 1984 to 81 in 2020. On the other hand, no statistically significant increase has been found in the city's precipitation trend from 1976 to 2015. Furthermore, the flooding risk is likely to increase given the historical pattern of urban expansion and its current speed, as the number of flooding susceptible woredas increase to 90 in 2030 under the business-as-usual scenario. Thus, smart growth management on urban expansion and dense inner-city development are recommended to reduce the flooding risk. [ABSTRACT FROM AUTHOR]

This work investigates the autonomous adaptive capacity of populations in flood-prone areas in the city of Belem (state of Para) in the Amazon region of Brazil. Autonomous adaptive measures are behaviors that the population adopts without explicit planning or the assistance of either institutions, professionals, or both, all of which are focused on protecting themselves from risks. This research focuses near the part of superficial drainage channels, which is divided into five areas. Visits to the study area and interviews with residents allowed to identify urban typologies and autonomous adaptive constructive techniques, as well as the relationship between these forms of adaptation and the socioeconomic conditions of the population. The main results are associated with the main motivations, information and knowledge that support flood adaptation strategies and the consequences of their success or failure in Amazonian cities. Some of them indicates that autonomous flood adaptation measures were not provided with professional technical assistance or externally financed; the measures are associated with structural modifications (e.g., raise the level of the properties and improve the building) and non-structural modifications (e.g., shims). Some of the conclusions are associated with sources of information; community recognition of flood adaptation methods; motivation to the measures implemented autonomously; consequence to the urban planning and people internal migration, and the difficulties to identify and characterize an adaptation measure as proactive or reactive in recurrent flood cycles in Amazonian cities. [ABSTRACT FROM AUTHOR]

As a result of climate change, urban areas are increasingly vulnerable to flooding, which can cause devastating effects, both in terms of loss of life and property. Therefore, an accurate assessment of urban flood processes and improved pre-disaster mitigation strategies in threatened areas is essential. Urban flood modeling enables users to understand, assess, and forecast flood conditions as well as their impact. For effective flood modeling, especially in highly urbanized floodplains, model selection based on the contextual requirements is a challenge. This review provides a systematic overview of the application of urban flood modeling approaches from the perspective of urban flood strategy design sequences. In this review, recent research advances are presented as well as suggestions for future research topics that will improve the availability and reliability of urban flood modeling methods. The results of this review will help urban flood managers and potential users balancing model complexity and needs while undertaking effective flood modeling tasks. [ABSTRACT FROM AUTHOR]

Climate change-induced floods have diversified effects on the physical and economic system of the dwelling societies. These effects mainly hit agricultural livelihood and livestock ending up in poverty. These irreversible damages are associated with high magnitude and frequency of floods, which are common in the South Asian countries. Similarly, Pakistan was hit hard by 2010 floods which were biggest in history as affecting over 20 million people and causing loss of over US$ 10.85 billion. The devastations were extended to rural poor communities of north-western part of Malakand division in Khyber-Pakhtunkhwa province of Pakistan, which were studied in this research on deploying 500 questionnaires at household level. It was to evaluate the extend of damages to livelihood and economic status of locality. Furthermore, this study tried to analyse the rise in poverty level, compared to the situation before inundating event of 2010. The results of cross-tabulation and logistic regressions confirmed that 1% increase in floods led to 0.44%, 0.31% decrease in livelihood and economic status, respectively. It was also found 1% increase in flooding ended up in 1.947% increase in the poverty level at household level. Further, the loss of livelihood resulted in the economic losses due to damages to crops and livestock and caused rise in poverty. The poverty syndrome was coupled with loss of savings and borrowing of funds that further ruined the economic situation of the locality. Conclusively, the flooding was declared to have posed adverse impacts on sustainable livelihood provision and rise in poverty in the area as not yet addressed through any institutional/governmental intervention. [ABSTRACT FROM AUTHOR]

Climate variability and changes in contemporary society such as increasing population, poor urbanization and expansion of residential areas are increasing the vulnerability and frequency of flooding hazards in Pakistan, especially in Khyber Pakhtunkhwa (KP) Province. Minimizing flood vulnerability needs an understanding of the factors that drive vulnerability to flooding hazard. The present study was conducted in the flood-prone areas of Peshawar, a district of KP, to evaluate flood vulnerability of the population using the Method for the Improvement of Vulnerability Assessment in Europe. Following this framework, an extensive literature review was conducted to develop relevant proxy indicators. Structured questionnaires were used for household surveys to collect data from 210 households in seven selected sites through simple random sampling method. The vulnerability factors, i.e., exposure, susceptibility and resilience, as well as the overall vulnerability were calculated and compared using ArcGIS tools. Results show that the overall vulnerability and the factor vulnerability of the studied sites were very high. Susceptibility and exposure factors were found to greatly influence vulnerability, and communities had low resilience in the face of flooding hazard. Addressing these indicators properly in developing strategies can reduce vulnerability and increase capacity of the communities to cope with floods in the future. Additionally, the government and disaster management agencies can play a significant role in minimizing the vulnerability to floods by strengthening physical and socioeconomic capacities through education, training and awareness about precautionary and mitigation measures. [ABSTRACT FROM AUTHOR]

Due to gradual sea level rise and changes in the climate system, coastal vulnerability to storm surge hazards is expected to increase in some areas. Studies regarding the effect of storm surge inundation on buildings and human lives, especially when it comes to relatively low-threat level events, have been few, however. In this research, storm surge load impact around coastal residential areas was quantitatively assessed, through fine-resolution numerical modelling. Meso- and street-scale simulation results for a storm surge event in Nemuro, Japan, were comprehensively validated against observations and field measurements, and the simulation results showed good accuracy for sea level, significant wave height and inundation area. A fine-resolution, street-scale coastal flood simulation was carried out with individual and grouped buildings, created with a building block model, and the results showed the significant role of buildings by realistically capturing inundation dynamics. Hydrodynamic results showed that coastal flood impact on buildings was insignificant (consistent with surveys). Lastly, the potential flood impact on people in the streets was investigated, using five human instability equations, where the most pessimistic results showed average values between 0.0 and 0.2 (max 0.6–0.7), and slightly below 0.4 for children and the elderly, respectively. These values indicated that threat levels during the Nemuro storm event were low, which corresponded with observations (no fatalities). This study framework could be applied wherever an accurate local storm surge threat estimate was required. [ABSTRACT FROM AUTHOR]

This study focused on flood damage assessment for future floods under the impact of climate change. Four river basins of Southeast Asia were selected for the study. They included the Pampanga River Basin (PRB) in the Philippines, the Solo River Basin (SRB) in Indonesia, the Lower Mekong River Basin (LMRB) in Cambodia and Vietnam, and the Chao Phraya River Basin (CPRB) in Thailand. Flood damage to rice crops was assessed by flood damage functions considering flood depth and duration and the growth stage of rice plants. Flood characteristics such as flood depth, duration, and distribution were computed using the rainfall–runoff–inundation model to assess flood hazards under the present and future climatic conditions produced by MRI-AGCM3.2S. The damage assessment methodology for rice crops employed in this study was verified using data on past flood events. Then, flood damage assessment was conducted for both the present climate (1979–2003) and future climate (2075–2099) conditions, using MRI-AGCM3.2S precipitation datasets. Flood damage was assessed for worst cases chosen from each climate period and for floods of 50- and 100-year return periods with different rainfall patterns chosen from each climate scenario. The results of flood hazard and damage assessment show that the flood inundation area for a 100-year flood may increase in the future by 20% in PRB; by 66% in SRB; by 27% in LMRB; and by 27% in CPRB. The flood damage area of paddy fields for a 100-year flood may also increase in the future by 16% in PRB; by 55% in SRB; by 23% in LMRB; and by 13% in CPRB. [ABSTRACT FROM AUTHOR]

This study assesses and evaluates the impacts of future extreme rainfall event(s) on conveyance capacity of urban Storm Water Network (SWN) of Hyderabad City, India, along with flood risk analysis and inundation mapping. The catchment runoff volume was simulated using Storm Water Management Model (SWMM). The runoff simulations were carried out for historic and future extreme rainfall event(s). Future rainfall events were simulated under climate change scenarios using Global Climate Model (GCM), GFDL-CM3 of Coupled Model Intercomparison Project Phase 5 (CMIP5). Nonlinear regression-based statistical downscaling was used to obtain rainfall at regional scale for Representative Concentration Pathways (RCPs) 2.6, 4.5, 6.0 and 8.5. It was found that RCPs 2.6, 4.5, 6.0 and 8.5 predicted a future extreme rainfall of 693 mm, 431 mm, 282 mm and 564 mm for the years 2088, 2098, 2040 and 2068, respectively. SWMM results indicated that the future extreme rainfall in Hyderabad can result in increased runoff volumes causing flooding. The existing SWN was capable of handling RCP 6.0 with 82% runoff. However, it was inadequate to convey runoff from RCPs 2.6, 4.5 and 8.5. Modelling results suggest that the conveyance capacity of storm drains can be increased by 25–30% by desilting major drains and outlets. [ABSTRACT FROM AUTHOR]

Pakistan is alarmingly exposed and vulnerable to flood disasters as a result of rapid urbanization that has not taken into account the threats posed by climate change. The devastating impacts of floods and other natural disasters put extra pressure on the country’s budget and has driven the country’s leadership to adopt a proactive approach instead of traditional, aid-based, approach, one that encourages the inclusion of disaster risk reduction measures within local disaster management policies. This research elaborates household vulnerability and resilience to flood disaster within two districts within Pakistan. It uses a dataset of 600 households collected through face-to-face interviews from two districts within the Khyber Pakhtunkhwa province that were severely affected by the 2010 flood and data from the Directorate of Khyber Pakhtunkhwa Provincial Disaster Management Authority. In a second step, we assigned weights to the selected variables for vulnerability (exposure, susceptibility and adaptive capacity) and resilience (with social, physical, economic, and institutional components) and used a subjective method (based on expert judgment) to weight these. The survey findings revealed that both study areas were highly vulnerable and had low resilience to flood disasters. The study findings indicated that community households in the flood-prone areas of Nowshera district were more vulnerable and less resilient than those in Charsadda, with a higher composite vulnerability index scoring and a lower composite resilience index score. This study shows that provincial and local disaster management authorities can play a vital role in reducing vulnerability and that more efforts are required to strengthen social, physical, economic, and institutional resilience through capacity-building training, preparedness, and awareness building about preventing and mitigating flood damage. [ABSTRACT FROM AUTHOR]

Flooding is a major threat to the local communities in the UK, and the risks are increasing due to climate change. Encouraging homeowners to prepare for the consequences of catastrophic flooding is imperative. This study aims to examine the ways in which individuals' risk perceptions and socio-cultural characteristics co-determine the preparedness for flood hazards. It is based on a social survey about household arrangements that can reduce the economic losses arising from flooding and enhance community resilience. A total of 485 responses were solicited from homeowners in England and Wales. Results confirm that the intention to act is socially motivated. This indicates the need for addressing the role of social networks and engagement with local community in enhancing community resilience to flooding. On the other hand, the effect of risk-related considerations is complicated. Perceived severity of flood damage is associated with intended actions, whereas risk characteristics are not. This implies that although providing relevant risk information to the public is crucial, appealing to the feelings of fears and uncertainties is less likely to be effective in driving actions for managing flood risks than has been usually assumed. The findings have practical implications for policy-making and climate risk communication. [ABSTRACT FROM AUTHOR]

Future trends in the occurrence of heat waves (HW) over Pakistan have been presented using three regional climate models (RCMs), forced by three different global climate models (GCMs) runs under RCP8.5 scenarios. The results of RCMs are obtained from CORDEX (Coordinated Regional climate Downscaling EXperiment) database. Two different approaches for the assessment of HWs are defined, namely Fixed and Relative approaches. Fixed approach is defined for a life-threatening extreme event in which the temperature can reach more than 45 °C for a continuous stretch of several days; however, Relative approach events may not be directly life-threatening, but may cause snow/ice melt flooding and impact on food security of the country in summer and winter seasons, respectively. The results indicate a consistent increase in the occurrence of HWs for both approaches. For the Fixed approach, the increase is evident in the eastern areas of Pakistan, particularly plains of Punjab and Sindh provinces which host many big cities of the country. It is argued that the effect of HWs may also be exacerbated in future due to urban heat island effect. Moreover, summer time HWs for Relative approach is most likely to increase over northern areas of the country which hosts reservoirs of snow and glacier, which may result in events like glacial lake outburst flood and snow/ice melt flooding. Furthermore, the increase in winter time HWs for Relative approach may affect negatively on the wheat production, which in turn can distress the overall food productivity and livelihoods of the country. It is concluded that this study may be a useful document for future planning in order to better adapt to these threats due to climate change. [ABSTRACT FROM AUTHOR]

There is observational evidence that hydrometeorological extremes, such as heavy rainfall events, have become more frequent and intense in the last decades around the world. In Brazil, intense rainfall events that triggered flash floods and landslides were responsible for 74% of the deaths related to natural disasters in the 1991-2010 period. To evaluate Brazil's hot spots of vulnerability to these disasters, two indices were developed using three data sets: (1) climate, with IPCC climate extreme indices; (2) environmental, including land use, drainage systems, relief, slope, road density and hydrography; and (3) socioeconomic, including the Gini coefficient, Human Development Index, housing conditions and a poverty-related index. Simulations at high resolution were carried out using the Eta 20-km regional climate model nested within two global climate models: HadGEM2 ES and MIROC 5 IPCC AR5 models. For the baseline period of 1961-1990, the vulnerability indices were adjusted by means of an iterative process and were validated by comparing them to the Brazilian National Disasters Data. The two indices were also used to estimate the vulnerability up to the end of the twenty-first century, using the representative concentration pathways (RCP) 4.5 and 8.5 from the IPCC AR5 RCP scenarios. The results indicate a large increase in Brazil's vulnerability to landslides and flash floods in the context of climate change. [ABSTRACT FROM AUTHOR]

Climate change is expected to result in an increase in the frequency and intensity of extreme weather events. In turn, this will result in more frequent occurrences of extreme flood events, such as flash flooding and large-scale river flooding. This being the case, there is a need for more accurate flood risk assessment schemes, particularly in areas prone to extreme flooding. This study investigates what type of flood hazard assessment methods should be used for assessing the flood hazard to people caused by extreme flooding. Two flood hazard assessment criteria were tested, namely: a widely used, empirically derived method, and recently introduced, physically based and experimentally calibrated method. The two selected flood hazard assessment methods were: (1) validated against experimental data, and (2) used to assess flood hazard indices for two different extreme flood events, namely: the 2010 Kostanjevica na Krki extreme river flood and the 2007 Železniki flash flood. The results obtained in this study suggest that in the areas prone to extreme flooding, the flood hazard indices should be based on using the formulae derived for a mechanics-based analysis, as these formulations consider all of the physical forces acting on a human body in floodwaters, take into account the rapid changes in the flow regime, which often occur for extreme flood events, and enable a rapid assessment of the degree of flood hazard risk in a short time period, a feature particularly important when assessing flood hazard indices for high Froude numbers flows. [ABSTRACT FROM AUTHOR]

Since recently, the potential of torrential downpour is increased and the flood damage shows increasing trend, in this study, the method to assess the flood vulnerability was established for the industrial parks, which is the driving power of the economic growth in Korea, and the results were analyzed. The vulnerability of each industrial parks was analyzed using three indicators: climate exposure, sensitivity and the adaptation ability, and the indicator value was calculated by selecting the proxy variable by each indicator. Among the primarily indicators, the final indicators were selected through the site investigation and in-depth interview. The vulnerability assessment was performed not only for the present but for the future (2020s, 2050s and 2100s). In the analysis results, Ulsan Mipo National Industrial Park was the most vulnerable for the present but in 2020s, Gwangyang National Industrial Park and Myeongji-Noksan National Industrial Park in 2050s and 2100s were assessed as most vulnerable. In the results of flooding vulnerability assessment, south coast industrial parks are the most vulnerable region during baseline and future. In addition, such industrial parks mostly built in the early phase of industrialization and they have advantage in import and export but were represented to be highly vulnerable due to aged infrastructures. In the industrial parks, as the enterprises are concentrated, it is easy to exchange the information and logistics, but the damage of natural disasters due to flooding can be aggravated due to the characteristics of the concentration. Actually, there are some cases that the industrial parks and the enterprises received the flooing damage in the highly vulnerable area by the torrential downpour. In this study, the vulnerability assessment was performed for the flooding damage by the torrential downpour for the industrial parks and the potential that the this study can be used as a useful decision-making tool in deciding the priority of adaptation ability was confirmed. [ABSTRACT FROM AUTHOR]

Devils Lake, a terminal saline lake in eastern North Dakota, has experienced catastrophic flooding over the past two decades producing direct damages in excess of $1 billion ($USD). We use three long-term datasets to examine the temporal coherence between historical lake fluctuations and basic hydroclimatic drivers. Monthly precipitation and mean monthly air temperature data are used to characterize long-term precipitation delivery and evaporative demand. Monthly water balance data for a representative location are used to assess basin soil moisture conditions. A lake volume time series documents lake volume fluctuation in response to long-term precipitation and regional soil moisture conditions. Three variables are derived from the datasets, each characterizing a different aspect of the region's hydroclimatology. A rescaling technique is applied to each variable to examine the temporal coherence and relative patterns of the variables and to identify distinct homogeneous hydroclimatic regimes during the historical period. The three rescaled variables show strong temporal coherence and confirm 1980 as an abrupt transition year between two distinct long-term hydroclimatic modes. Mode 1, a longer and drier phase, runs from 1907 to 1980, while mode 2, a shorter and wetter phase, extends from 1981 to the present. Multi-decadal and century-scale fluctuations between these two modes are the key drivers of long-term lake volume fluctuations, upon which interannual- and interdecadal-scale climatic variability are superimposed. The similar rates of change among the rescaled variables provides evidence in support of the conclusion that long-term natural hydroclimatological variability is the primary driver of observed lake volume changes at Devils Lake during the Twentieth Century and provides a foundation upon which to evaluate the potential contributing effects of anthropogenic climate change, and human alterations of the land use hydrology. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the spatial distribution of flood shelters in relation to flood hazards in a resource-poor country. Flood hazard estimates were developed from multi-temporal flood-affected frequency and floodwater depth maps. It is intended that the results could support non-structural flood management. In addition, the location of vulnerable housing units was mapped and their accessibility to shelters was computed with the aid of spatial techniques using a geographic information system. A subset of the Dhaka Metropolitan Development Plan zone and Dhaka megacity, covering an area of 878 km, was used as a case study since this area is likely to experience more frequent and intense flooding in coming years as a result of rapid urbanisation and climatic change. Using three different criteria, the study identified that a total of 5537 buildings, out of 6342 candidate structures, can be used as emergency shelters during floods, and approximately 145,000 dwellings (19.3 % of total residential units) of various types were located in places that are prone to flood. Further, many (3500 of 5537) of the identified shelters were not sufficiently close to vulnerable dwellings to protect approximately 496,000 potential flood victims during an emergency. There were 26.4 % of the total residents living in vulnerable housing units. In addition, 1098 flood shelters were distributed over five catchments in the study area, although in close proximity to vulnerable residents, do not have the capacity to house the number of people who could potentially seek refuge there. This study, the first of its kind in Dhaka, can assist urban planners and emergency managers in developing an effective evacuation plan for an imminent flood disaster as the city currently lacks any disaster management plan. [ABSTRACT FROM AUTHOR]

To incentivize more community flood risks mitigation, the US Congress implemented the community rating system (CRS) in 1990. The CRS seeks to help communities build capacity to address flood risks and become more resilient to future flood disasters. Communities participating in CRS can reduce their flood risks and enjoy discounted premiums (up to 45 %) on federally required flood insurance commensurate with their community's CRS score. A participant community is placed into one of the ten classes depending on its CRS score. Although previous research finds that the program's structure creates opportunities for communities participating in CRS to respond to its incentives, no study has examined the characteristics of communities that changed their mitigation behavior due to this incentive scheme. In order to evaluate the performance of CRS and its tiered incentive structure, this study investigates the extent to which communities are responding strategically to CRS incentives and the characteristics of those communities behaving strategically. This study uses a regression discontinuity approach to compare the characteristics of communities above and below CRS class thresholds. The results show strategic behavior of communities participating in CRS. Communities with more information-based flood management activities, lower property values, lower flood risk, and lower population densities are more likely to respond strategically with respect to smaller CRS subsidies. For larger subsidies, the results indicate that CRS communities with higher property values are more likely to respond strategically to the policy incentives. The study concludes with a discussion of the implications of these results for the CRS program. [ABSTRACT FROM AUTHOR]