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This study investigates the impact of green open spaces in reducing the probability of flooding and open waste burning in urban areas in Indonesia’s three largest metropolitan cities: Surabaya, Jakarta, and Medan. This study employs urban village microdata from the 2014 and 2018 Village Potential Census. First, we construct the dataset into a difference-in-differences setup. The urban villages that initially did not have any green open spaces in 2014 and then had them in 2018 were assigned as the treatment group, and those without any green open spaces in both periods were the comparison group. Then, we estimated the impact of urban green spaces on the probability of flooding and open waste burning. The results indicate that the likelihood of flooding and open waste burning had decreased in treated areas by 2018.

This paper introduces Neighbor Aware Adaptive Power flooding, an optimized flooding mechanism used in mobile ad hoc networks (MANETS) that employs several mechanisms (neighbor coverage, power control, neighbor awareness and local optimization) to limit the broadcast storm problem, reduce duplicate packet reception and lower power consumption in both transmission and reception. Upon receiving an optimized broadcast, a relay determines a new set of possible relays (to continue the flood) based upon local neighbor information and the previous optimized broadcast. Additionally, neighboring relays only consider the shared neighbors they are closest to. A relay may perform local optimization (to reduce power consumption and isolate broadcasts) by substituting one high power broadcast with two or more low power broadcasts, thereby introducing additional hops, We show that compared to blind flooding and multipoint relaying, NAAP in a static environment greatly reduces the problems associated with the broadcast storm problem, duplicate packet reception and power consumption.

Content networks are overlay networks, enabling access to distributed contents on centralized servers or individual computers. Since flooding-based routing scheme features poor scalability, we present a modification, which reduces the total network traffic while retaining the original efficiency. In choosy routing, as we call it, each node, while passing an answer, remembers which neighbor it came from. Subsequently repeated queries about the same content are forwarded only to that neighbor. This way, the network learns effective routes. The simulations on several topology types have shown the expected behavior, with up to three-fold reduction in the overall query traffic.

Unstructured peer-to-peer (P2P) networks suffer from the increased volume of traffic produced by flooding. Methods such as random walks or dynamic querying managed to limit the traffic at the cost of reduced network coverage. In this paper, we propose a partitioning method of the unstructured overlay network into a relative small number of distinct subnetworks. The partitioning is driven by the categorization of keywords based on a uniform hash function. The method proposed in this paper is easy to implement and results in significant benefit for the blind flood method. Each search is restricted to a certain partition of the initial overlay network and as a result it is much more targeted. Last but not least, the search accuracy is not sacrificed to the least since all related content is searched. The benefit of the proposed method is demonstrated with extensive simulation results, which show that the overhead for the implementation and maintenance of this system is minimal compared to the resulted benefit in traffic reduction.

The watershed transformation is a primary tool for segmenting a grey-tone image into subsets that are of interest to a visual observer. The resulting image, however, may often appear oversegmented into a large number of tiny regions (basins), most of which are not significant to the problem of domain. In this paper, a method for removing these nonsignificant basins is presented. The notions of relative significance and intrinsic significance are introduced, which lead to the definition of three types of significance for a basin: strong, weak and partial. The merging of a basin with other basins only occurs when the significance of the basin is not strong, and is restricted to suitably selected adjacent basins. The merging is performed by using an iterated process consisting of two phases. The first involves the removal of certain regional minima, and is accomplished by following either a flooding or a digging scheme. The second identifies the basins corresponding to the regional minima remaining in the image and utilizes the watershed transformation. An appropriate selection of the basins to be merged produces a segmented image perceptually close to the original image. The performance of the proposed method is for the case of astronomic images.

This paper reviews recent literature on flood research in Bangladesh, focusing on the nation's vulnerability to climate change and its ability to adapt. This review reveals that the literature on community-based vulnerability and adaptation, and their processes and assessments in response to hazards under climate change regimes are inadequate, apart from a recent focus on assessment of the vulnerability of rural communities, their ability to adapt their farming methods, or the economic consequences of failure to adapt in response to extreme flood events, e.g. Younus (2012a,b); Younus and Harvey (2013, 2014). This paper argues that an integrated assessment of rural vulnerability and community-based adaptation is needed in order to ensure sustainable changes in response to future climate change regimes in Bangladesh.

Future risks linked to extreme events and options for managing them are receiving increasing attention in the research and policy arena, where uncertainty is considered to be one of the most challenging aspects in regard to disasters triggered by natural hazards. To shed more light on this issue, this study conducts a detailed uncertainty assessment of a forward-looking country level catastrophe risk model for extreme flood events in Bangladesh and identifies how various sources of uncertainties contribute to the variability in modeling results. Alternative assumptions of climate, exposure and vulnerability parameters show that scenario uncertainty regarding socio-economic development — and exposure in particular — seems to dominate other sources of uncertainty. Importantly, this trend is particularly notable for the estimate of extreme events rather than annual average losses and for the prediction over the longer-time horizons rather than near future. It is concluded that there is ample need to better understand how future vulnerability and exposure will develop as they found to be core determinants of risk, apart from climate change, for increases in extreme losses. One viable way is the incorporation of bottom-up assessment of exposure asset build-up and further analysis of vulnerability drivers, which could reduce epistemic uncertainty regarding projection of catastrophic economic losses into future. It is suggested that the concept of “iterative risk management” may provide a feasible way to achieve reduction of these uncertainties in a step-by-step basis.

Local risk managers in New York City were keenly aware that the city’s residents, businesses, and infrastructure were vulnerable to significant flooding events before Hurricane Sandy hit in October 2016. The storm and its aftermath have influenced the structure of the city’s approach to risk management and urban development in many ways. The objective of this manuscript is to characterize the current risk management regime in New York City, how it is changing, and how it might shift with the further onset of climate change. More specifically, the paper addresses three basic questions: 1. How does current risk management policy in New York City intersect with climate change adaptation and urban development?; 2. Is there sentiment that transition to a new risk management paradigm is needed?; and 3. If transition is necessary, how will it be enabled or blocked by the current actors, organizations and policy-making networks for adaptation and risk management in the city? In the analysis we focus on examining the relative importance of a suite of possible factors and drivers. Two sources of data are reviewed and integrated. These include results from a workshop with local risk managers, and as well as face-to-face extended interviews with risk manager stakeholders and practitioners. The results indicate that there is significant need for a transition to wider and more comprehensive transformative adaptation policy but the means and opportunities to do is limited.

Sharing of risk knowledge for extreme events is taking place against a backdrop of changing societal communication patterns, in which the flow of information is increasingly multi-directional, within and between individuals, wider communities and a variety of authorities using online media. We present qualitative findings from the CASCADE knowledge exchange project and a case study, from a flood risk area, on the role of social networks using such ‘new’ media as engagement tools in building resilience to flooding. The data emerged from a workshop held in 2018, together with a study into changing communication practice in the Thames Valley near Windsor, UK. It was found that engagement is occurring both during events, as an emergency management tool, and between events, often linked to strategic management such as flood defense and related planning. The qualitative findings were analyzed to investigate whether knowledge and information sharing in emergencies may lead to co-operative sharing between emergencies. According to evidence from workshop discussions across the seminars, and empirical evidence from the flood risk zone, social networks formed and/or enhanced using new media can help promote consensus but also have the potential to accentuate distrust and divide managers and the community at risk. Relevant factors were the nature of the risk faced, nature of event-related protection activity, whether extreme weather events were occurring or had occurred in the recent past, and sociocultural aspects such as the degree of general engagement of civil society, linked to location. There is a possibility that new media may thus reinforce existing power structures, including acknowledged paternalistic attitudes by management authorities and pre-conceived ideas from at-risk communities. In terms of the contribution that social media can make toward the goal of social learning for resilience, the specific role of online social media as a communication tool continues to evolve. It was noted from the workshop that there is a potential for producers of information to act also as consumers (the ‘prosumer effect’), but gaining benefit from this trend requires some changes to existing interaction patterns within and between risk management authorities and communities. More investment may be required in forms of engagement that build relationships of trust, using ‘traditional’ (face-to-face) approaches.

Among natural disasters in Pakistan, flooding is the most frequent and devastating. In Punjab, the flood-prone areas suffer heavy damage during the heaving rainfall of the monsoon. The population density of Punjab region is increasing every year. Conversely, the dependence of population on rivers and urbanization on agricultural land is increasing every year. Many researchers tried to investigate flood mechanism and predict flood disasters. Researchers have mainly focused on the upstream of the Indus River due to flash flood disaster risk. At the downstream of Indus river, the high population density area after the confluence of the Indus and Chenab rivers is also important due to the riverine. In this region, severe inundation by flooding occurred in 2015. In this study, Rainfall-Runoff-Inundation Model (RRI) and River model (iRIC) were used to evaluate the inundation. We aimed to comprehensively evaluate the inundation risks (inundation depth, peak inundation discharge, and inundation area) by considering extreme rainfall events over densely populated areas located downstream of the confluence point of the Indus and Chenab Rivers. In addition, sensitivity experiments for land cover were conducted to reveal the impact of land-cover change (urbanization and afforestation) on inundation. The Nash-Sutcliffe model efficiency coefficient for river discharge calculation at the Tounsa barrage and Trimmu headworks (on just before the confluence point of Indus and Chenab) was 0.83 and 0.67 respectively. Furthermore, the flooding at the confluence point of the Indus River was reproduced by iRIC with high accuracy. The results showed that planting and afforestation will mitigate flooding scale, but urbanization increases the risk of flooding especially after the confluence point of two rivers at the high population dense area. Planting between the Indus River and Chenab River could mitigate flood disasters downstream of the confluence point.

Every year flooding and landslides cause severe material damages and thousands of deaths and injuries. To reduce the risk, measures can be taken by applying different management strategies either by reducing the probability of the event or by reducing the potential consequences in case of an event. This chapter provides a systematic (step-by-step) guidance, a brief overview of landslide and flood risk management in general and a summary of an investigation of the present risk management situation in Sweden which has resulted in some general recommendations. Examples of general recommendations are to apply available knowledge, for example by learning from existing good examples and, when available, lessons learned and documentation of the rational argumentation made in the decision process. There is a request of checklists and guides that can be used in the current daily work among planners and risk managers. It is important with a broad basis for decisions, therefore integrated assessments and valuations are recommended for example by applying multi-criteria analysis methodology and involving relevant stakeholders in the process for example through well working networks. It is further important to counteract the current trend that more automatic monitoring results in less field monitoring and reduced local knowledge.

Of all widespread natural hazards with large scale human, economic and environmental impacts, flooding surpasses. In the urban areas, its threats are substantial and calls for ever more attention. Urban flooding, a relatively new hazard phenomenon, is a key global issue due to the economic and political significance of cities. Flood risk management based on the UNISDR idea of living with floods rather than fighting them provides systematic techniques for tackling urban flooding. However, these techniques are undermined in many developing countries (DCs) such as Nigeria and Bangladesh due to the insufficiency or lack of pertinent capacities, which are fundamental to best practices in flood risk management. The present study explores some of these capacities, drawing from urban flooding and management experiences in Lagos, Dhaka and Maputo. Among other issues, the idea of resilient cities and communities as well as sustainable development will be realistic in the DCs only if adequate attention is given to capacity development.