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Focusing specifically on the topic of flood risk in mountainous regions, the book can be viewed as a sort of manual for EWS designers, managers, and users. It is organised into different independent sections which will appeal both to experts as well as those with an interest in the subject. Most of results can also be exported to other hazards

Malaysia experiences a major flood event every three years due to the adverse effects of two monsoon seasons a year. Floods have thus become the most significant natural disaster in the country in terms of the population affected, frequency, aerial extent, financial cost and the disruption to socio‐economic activities. Many previous flood control measures have had different levels of success but have generally had little effect in reducing the problem. However, it is now understood that it is neither possible nor desirable to control floods completely. Spatial information technology is thus being increasingly recognized as the most effective approach to flood disaster management. This paper reviews the spatial information technology in flood disaster management and its application in Malaysia. Some flood forecasting systems are discussed, along with their shortcomings. The paper discusses the framework of a proposed flood early warning system for the Langat river basin that operationally couples real‐time NOAA‐AVHRR data for quantitative precipitation forecasting with hydrologically oriented GIS and a MIKE11 hydrodynamic model.

Abstract
Flood early warning systems (FEWS) are essential in mitigating flood damage. To optimize their effectiveness, it is important to understand how people respond to warnings and prepare for flooding events. The key factors influencing social preparedness include 1) direct and 2) indirect experiences of floods and 3) trust in warnings. However, existing sociohydrological models do not incorporate all these elements. To include these elements for social preparedness, we propose an idealized model that allows multiple regions to influence one another (i.e., regional interactions). We investigate the dynamics of social preparedness in a society composed of regions with varying infrastructure levels (e.g., levee heights) and explore strategies for developing a socially efficient FEWS. Numerical analyses reveal that in a society that has a region characterized by a low infrastructure level (i.e., a region with frequent floods), regional interactions lead to a pronounced cry wolf effect due to false alarms from other regions, diminishing social preparedness in the low-infrastructure region. These interactions also prevent a warning strategy that optimizes the natural-science-based index (i.e., threat score) from maximizing social efficiency. Conversely, in a society that has a region characterized by a high infrastructure level (i.e., a region with infrequent floods), regional interactions enhance the efficiency of FEWS by improving social preparedness through indirect experiences with floods. These findings suggest that as regional heterogeneity increases, it becomes increasingly vital for forecasters to consider social aspects (e.g., people's experiences, trust, and interactions) when establishing a socially efficient FEWS. The refined model will be valuable to forecasters in designing effective FEWS in real-world situations.

This paper describes the issues relating to the role of the flash flood early warning system provided by the Malaysian Government to the communities in Malaysia, specifically during the flash flood disaster in the Cameron Highlands, Malaysia. Normally, flash flood disasters can occur as a result of heavy rainfall in an area, and that water may possibly cause flooding via streams or narrow channels. The focus of this study is the flash flood disaster which occurred on 23 October 2013 in the Cameron Highlands, and as a result the Sungai Bertam overflowed after the release of water from the Sultan Abu Bakar Dam. This release of water from the dam caused flash flooding which led to damage to properties and also the death of residents and livestock in the area. Therefore, the effort of this study is to identify the perceptions of the flash flood victims on the role of the flash flood early warning system. For the purposes of this study, data were gathered through face-to-face interviews from those flood victims who were willing to participate in this study. This approach helped the researcher to glean in-depth information about their feelings and perceptions of the role of the flash flood early warning system offered by the government. The data were analysed descriptively and the findings show that the respondents of 22 flood victims believe strongly that the flash flood early warning system was confusing and dysfunctional, and communities had failed to response positively to it. Therefore, most of the communities were not well prepared for the releasing of water from the dam which caused property damage, and 3 people were killed in the Cameron Highland flash flood disaster.

Includes bibliographical references (leaves 107-117). ; This thesis examines the feasibility of applying people-centred approaches to flood early warning systems (EWS) in informal settlements in the City of Cape Town, particularly, through the experiences of poor and disadvantaged communities in Kosovo and Masiphumelele informal settlements. The impact of recurrent floods during the winter rainfall months and their costs are disproportionally borne both by those at risk and the local government that is required to repeatedly respond to them. A social science perspective is adopted, with the application of a risk communication framework. The urban flood-risk context of both study sites and the risk governance approach to managing and communicating flood risk were investigated and factors influencing flood warning processes and behavioural factors influencing response to flood-risk and flood warning, examined.

Abstract. Floods remain a wicked problem and are becoming more destructive with
widespread ecological, social, and economic impacts. The problem is acute in
mountainous river catchments where plausible assumptions of risk behaviour
to flood exposure and vulnerability are crucial. Inclusive approaches are
required to design suitable flood early warning systems (EWSs) with a focus
on local social and governance context rather than technology, as is the case
with existing practice. We assess potential approaches for facilitating
inclusiveness in designing EWSs by integrating diverse contexts and
identifying preconditions and missing links. We advocate the use of a
SMART approach as a checklist for good practice to facilitate
bottom-up initiatives that benefit the community at risk by engaging them at every stage of the decision-making process.

Abstract. This paper focuses on the use of community-based early warning systems for flood resilience in Nepal. The first part of the work outlines the evolution and current status of these community-based systems, highlighting the limited lead times currently available for early warning. The second part of the paper focuses on the development of a robust operational flood forecasting methodology for use by the Nepal Department of Hydrology and Meteorology (DHM) to enhance early warning lead times. The methodology uses data-based physically interpretable time series models and data assimilation to generate probabilistic forecasts, which are presented in a simple visual tool. The approach is designed to work in situations of limited data availability with an emphasis on sustainability and appropriate technology. The successful application of the forecast methodology to the flood-prone Karnali River basin in western Nepal is outlined, increasing lead times from 2–3 to 7–8 h. The challenges faced in communicating probabilistic forecasts to the last mile of the existing community-based early warning systems across Nepal is discussed. The paper concludes with an assessment of the applicability of this approach in basins and countries beyond Karnali and Nepal and an overview of key lessons learnt from this initiative.