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Models for shallow water wave processes are routinely applied in coastal, estuarine and river engineering practice, to problems such as flood waves, tidal circulation, tsunami penetration, and storm tides. Evaluation and confirmation of application codes can be facilitated by analytical solutions that may represent this wide range of physical problems, without significantly compromising the contributing flow processes. The appropriate linearized shallow water wave equations are defined, together with quite general initial and boundary conditions that will represent the expected variety of shallow water wave problems. A completely general analytical solution for both water surface elevation and flow is established, in a manner suitable for the evaluation of shallow water wave codes. The contribution of both free and forced modes is identified, together with the role of friction.

A sequence of analytical solutions explore the spectrum of response patterns expected from numerical codes for flood and tide propagation in channels. Complete analytical details of the solutions are provided, together with specific suggestions for an associated set of analytical benchmark tests. Illustrations of predicted response patterns provide the basis for a discussion of many significant physical aspects and their representation in discrete numerical codes.

The position and configuration of the coastal shelf of the northern Bay of Bengal amplify the storm surge height extraordinarily. The low-lying coast of Bangladesh is severely devastated when extreme surges hit the land. However, the influence of track of a cyclone on surge height is not well known. A calibrated numerical model is used to simulate series of storm surges for a severe cyclone by shifting its track position and angle. The cyclonic wind field has been generated using the extreme parameters adopted from historical measurements. Surge heights simulated by the two-dimensional model are compared at selected locations along the coast. It was found that the cyclone with a landfall location at Barguna, a place between the Sundarban and the Meghna Estuary, develops the highest surge of 12.0 m (PWD) at the northeast of the estuary. The magnitude is further amplified to 13.0 m (PWD) when the surge coincides with the high-tide condition; a surge of similar magnitude attacked the coast of Bangladesh in 1876. Change in track orientation shows little influence on surge heights at the eastern coast. However, relatively higher effect was found in the western coast. Surge height distribution has also been presented with respect to local land or embankment elevation for the extreme event. A flood map is produced showing inundation depth in the aftermath of the extreme surge attack. The coastal areas at the northern tip of the upper bay and the western banks of the Meghna Estuary are found to be the most vulnerable locations.

Usually simulations on environment flood issues will face the scalability problem of large scale parallel computing. The plain parallel technique based on pure MPI is difficult to have a good scalability due to the large number of domain partitioning. Therefore, the hybrid programming using MPI and OpenMP is introduced to deal with the issue of scalability. This kind of parallel technique can give a full play to the strengths of MPI and OpenMP. During the parallel computing, OpenMP is employed by its efficient fine grain parallel computing and MPI is used to perform the coarse grain parallel domain partitioning for data communications. Through the tests, the hybrid MPI/OpenMP parallel programming was used to renovate the finite element solvers in the BIEF library of Telemac. It was found that the hybrid programming is able to provide helps for Telemac to deal with the scalability issue.

In recent years, as the international community pays increasing attention to disaster prevention and reduction, study on vulnerability has become a new focus in the science of disaster, and it gradually becomes a consideration in strategy-making for sustainable social development. Understanding of vulnerability has become a prerequisite for grasping the nature of disasters, and it is also an area where humans can make a difference in disaster prevention and mitigation. Based on historical disasters and the concepts of vulnerability, this study applies the CCR model, one of the most basic Data Envelopment Analysis (DEA) models, to analyze the pattern of variation regarding agricultural vulnerability to floods in Shanghai suburban areas. The results prove the following: chronologically, the overall vulnerability degrees of Shanghai suburbs listed in the descending order are $1991>1983>1984>1981>1985>1979>1986>1990>1980>1989>1987>1988$; spatially, based on the averages recorded in 2013, the vulnerability levels of Shanghai suburban districts are Nanhui $>$ Jinshan $>$ Songjiang $>$ Baoshan $>$ Qingpu $>$ Pudong $>$ Jiading $>$ Fengxian. The results are basically consistent with the fact. Based on the characteristics of each district’s vulnerability to floods, some suggestions for flood prevention and mitigation are provided. The assessment models of flood vulnerability are simple and can be used for vulnerability analysis of natural disasters at regional or national levels. The assessment method adopted in this paper contributes to a deeper understanding of agricultural vulnerability to floods in Shanghai and provides a scientific base for the decision-making of related departments.

Urban growth, in many Asian cities, may lead to increased exposure to flood and growing sensitivity mainly because of the presence of informal settlements. On the other hand, urban areas may offer better access to public facilities, improving adaptive capacity and enhancing the local government’s capabilities. This study aims to investigate to what extent urban growth exacerbates flood vulnerability in Central Java. Concurrently, floods are the most frequent disaster in the area. The approach used in the vulnerability assessment involves socioeconomic conditions (population density, the number of impoverished families, public facilities) associated with three main aspects (exposure, sensitivity, and adaptive capacity), resulting in the Exposure and Sensitivity Index and the Adaptive Capacity Index. Scoring and weighting analysis using secondary data in a sub-district unit from the Central Bureau of Statistics are applied. The result shows that urban growth contributes to the escalation of hazards and vulnerability. On the other hand, a high population also increases the number of public facilities and affects adaptive capacity in certain areas. Indeed, strategic urban development policies are critical to manage the three elements that form the flood vulnerability.

Severe flooding events often cause significant damage to an area, including affecting the local economy, disrupting transportation, and damaging infrastructure. While raw statistics offer some understanding of crop and property-related damages, resulting from large-scale floods, we also need to consider the longer-term impacts and recovery within an area and the interaction between adjacent areas during the recovery process. In this paper, we examine the impacts of major and minor flood events on business employment and the number of establishments in different sectors of the economy. While we find that flood events had a negative short-run impact on agricultural services and particularly small establishments, estimations show positive impacts in the service sector. We also identify significant spatial spillovers.

We measure the impact of extreme weather events—droughts and floods—on health-care utilization and expenditures in Sri Lanka. We find that frequently occurring local floods and droughts impose a significant health risk when individuals are directly exposed to these hazards. Individuals are also at risk when their communities are exposed even if they themselves are unaffected. These impacts, especially the indirect spillover effects to households not directly affected, are associated with land use in affected regions and access to sanitation and hygiene. Finally, both direct and indirect health risks associated with floods and droughts have an economic cost: our estimates suggest that Sri Lanka spends $19 million per year directly on health-care costs associated with floods and droughts. This cost is divided almost equally between the public purse and households, with 83% of it spent on flood-related health care and the rest on drought-related health care. In Sri Lanka, both the frequency and intensity of droughts and floods are likely to increase because of climatic change. Consequently, the health burden associated with these events will likely increase.

Disasters, predicted to increase in intensity and frequency in the near future as a result of climate change, are cross-scale in their impact, disrupting functioning across multiple levels of socio-cultural systems in which individuals’ lives are embedded. Governments all over the world need policies to plan support for community preparedness and recovery from disasters and to this end they need to understand and model disaster resilience as accurately as possible. Disasters can be either rapid or slow onset events, requiring differing responses to facilitate resilience. These might be at community and/or individual scales. The interconnectedness of resilience at individual and community scales requires multilevel preparedness, responses and mitigation strategies. A useful lens with which to investigate these interconnections for policy creation is Bronfenbrenner’s bioecological theory. This chapter describes research conducted in four disaster impacted regional Australian towns using Bronfenbrenner’s bioecological theory to assess and model disaster resilience. The four sites experienced flood, cyclone, bushfire and drought respectively, resulting in damage running into many millions of dollars. The research validated the use of Bronfenbrenner’s theory for modeling disaster resilience. Results highlighted several important areas for targeted government policy to promote disaster resilience, manage risk and reduce individuals’ vulnerability in diverse settings.

This paper studies on interactions between morphological changes and wave and current fields around the Tenryu River mouth during a severe storm. Installing six cameras, authors successfully captured collapse of sand bar around the Tenryu River mouth when typhoon T0704 hit the Pacific Coast of Japan in July 2007. Obtained images were analyzed based on several image processing techniques and, coupled with the other hydrodynamic data, showed clear evidence for interactive features of bathymetry changes and surrounding wave and current fields. Finally, a numerical model based on depth-integrated non-linear shallow water equations and energy balance equations were applied to the observed conditions and it was found that topography changes during the storm was one of the most essential factors that determine the characteristics of surrounding wave and current fields.