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The Ba River catchment and delta on the island of Viti Levu, Fiji, supports a wealth of livelihoods and is populated by diverse communities who are living with an increased frequency and intensity of hydro-meteorological hazards (floods, cyclones and droughts). Participatory mapping as part of focus group discussions is a tool that can be used to elucidate communities’ understanding of the differing impacts of multiple hazards, as well as the strategies used to prepare and respond to different hazards. In this chapter, the authors present the results of qualitative research undertaken with members of three communities along the Ba River, from the Nausori highlands to the coastal mangroves, with a particular focus on recent floods (2009, 2012) and Tropical Cyclone Winston (2016). The communities draw on a wide range of livelihood strategies from fishing and agriculture to tourism and outside work. Natural hazard events vary in their impact on these livelihood strategies across the landscape and seascape, so that community members can adjust their activities accordingly. The temporal ‘signatures’ of ongoing impacts are also variable across communities and resources. The results suggest that taking a broad, landscape (and seascape) approach to understanding how communities draw livelihoods is valuable in informing effective and inclusive adaptation strategies for environmental change. Furthermore, documenting how the landscape is used in a mapped output may be a valuable tool for future social impact assessment for resource extraction activities.

The overall objective of this study is envisaged to provide decision makers with actionable insights and access to multi-risk maps for the most in-danger stave churches (SCs) among the existing 28 churches at high spatial resolution to better understand, reduce and mitigate single- and multi-risk. In addition, the present contribution aims to provide decision makers with some information to face the exacerbation of the risk caused by the expected climate change.

Material and data collection started with the consultation of the available literature related to: (1) SCs' conservation status, (2) available methodologies suitable in multi-hazard approach and (3) vulnerability leading indicators to consider when dealing with the impact of natural hazards specifically on immovable cultural heritage.

The paper contributes to a better understanding of place-based vulnerability with local mapping dimension also considering future threats posed by climate change. The results highlight the danger at which the SCs of Røldal, in case of floods, and of Ringebu, Torpo and Øye, in case of landslide, may face and stress the urgency of increasing awareness and preparedness on these potential hazards.

The contribution for the first time aims to homogeneously collect and report all together existing spread information on architectural features, conservation status and geographical attributes for the whole group of SCs by accompanying this information with as much as possible complete 2D sections collection from existing drawings and novel 3D drawn sketches created for this contribution. Then the paper contributes to a better understanding of place-based vulnerability with local mapping dimension also considering future threats posed by climate change. Then it highlights the danger of floods and landslides at which the 28 SCs are subjected. Finally it reports how these risks will change under the ongoing impact of climate change.

This paper places a college at the centreof a multi-hazard assessment (earthquake, flood and landslide). The college is within a less studied, rural area of Ladakh, North India. Research focusses on a case study (Students Educational and Cultural Movement of Ladakh (SECMOL) College), close to Leh, Ladakh, and extends to incorporate/apply thinking from/to the wider Ladakh region. The approach adopted, centring on the hazard assessment of a single entity/local area, allows a rapid uptake of hazard recommendations within a college environment planning to continue its existence for decades ahead. A sister paper (Petterson et al., 2019) documents the active involvement of college staff and students in the principles of geohazard assessment and the development of student-centric hazard assessments of the college and their home village. SECMOL is a self-sufficient, alternative, college, organised along strong environmentally sustainable principles. The paper aims to discuss these issues.

This work has adopted different strategies for different hazards. Fieldwork involved the collection of quantitative and qualitative data (e.g. shape and size of valleys/river channels/valley sides, estimation of vegetation density, measurement of sediment clasts, angle of slopes, assessment of sediment character, stratigraphy of floodplains and identification of vulnerable elements). These data were combined with satellite image analysis to: define river catchment character and flood vulnerability (e.g. using the methodology of Collier and Fox, 2003), examine catchment connectivity, and examine landslip scars and generic terrain analysis. Literature studies and seismic database interrogation allowed the calculation of potential catchment floodwater volumes, and the collation of epicentre, magnitude, depth and date of seismic events, together with recent thinking on the return period of large Himalayan earthquakes. These data were used to develop geological-seismic and river catchment maps, the identification of vulnerable elements, and disaster scenario analyses.

This research concludes that SECMOL, and much of the Ladakh region, is exposed to significant seismic, flood and landslide hazard risk. High magnitude earthquakes have return periods of 100s to c. 1,000 years in the Himalayas and can produce intense levels of damage. It is prudent to maximise earthquake engineering wherever possible. The 2010 Leh floods demonstrated high levels of devastation: these floods could severely damage the SECMOL campus if storms were centred close by. This study reveals the connectivity of catchments at varying altitudes and the potential interactions of adjacent catchments. Evacuation plans need to be developed for the college. Northern ridges at SECMOL could bury parts of the campus if mobilised by earthquakes/rainfall. Slope angles can be lowered and large boulders moved to reduce risk. This work reinforces recommendations that relate to building quality and urban/rural planning, e.g. using spatial planning to keep people away from high-risk zones.

The frequency of hazards is low, but potential impacts high to very high. Hazard mitigation actions include engineering options for hazardous slopes, buildings to be earthquake-proofed, and evacuation management for large floods.

Methodologies undertaken in this research are well-tested. Linkages between disciplines are ambitious and somewhat original. The application of this work to a specific college centre site with the capacity to rapidly take up recommendations is novel. The identification of catchment inter-connectivity in this part of Ladakh is novel. This work complements a sister paper (Petterson et al., 2019) for community aspects of this study, adding to the novelty value.

This study assesses the effects of flood hazard on property price, which focus on residential property. The growth in the population has resulted in more areas being explored, including areas that are prone to flooding. The exploration of a new area for housing development also brings vulnerability to flood hazard. This research employed hedonic regression method to assess the impact of flood to property price between low-flood and non-flood areas. The case study areas are residential properties along Langar River, Selangor, Malaysia. The findings reveal that residential price in case study areas have only little impact in terms of price impact from the flood events. This study also establishes a new valuation model by considering flood hazard. It is expected that the impact from the flood to property price will be significant in future due to changes in property demand patterns as well as the increase in environmental issues.

The purpose of this paper is to prepare flood hazard map and show the extent of flood hazard under climate change scenarios in Woybo River catchment. The hydraulic model, Hydrologic Engineering Center - River Analysis System (HEC-RAS) was used to simulate the floods under future climate scenarios. The impact of climate changes on severity of flooding was evaluated for the mid-term (2041–2070) and long-term (2071–2100) with relative to a baseline period (1971–2000).

Future climate scenarios were constructed from the bias corrected outputs of five regional climate models and the inflow hydrographs for 10, 25, 50 and 100 years design floods were derived from the flow which generated from HEC-hydrological modeling system; that was an input for the HEC-RAS model to generate the flood hazard maps in the catchment.

The results of this research show that 25.68% of the study area can be classified as very high hazard class while 28.56% of the area is under high hazard. It was also found that 20.20% is under moderate hazard and about 25.56% is under low hazard class in future under high emission scenario. The projected area to be flooded in far future relative to the baseline period is 66.3 ha of land which accounts for 62.82% from the total area. This study suggested that agricultural/crop land located at the right side of the Woybo River near the flood plain would be affected more with the 25, 50 and 100 years design floods.

Multiple climate models were assessed properly and the ensemble mean was used to prepare flood hazard map using HEC-RAS modeling.

The main objective of the study is to identify the vulnerable areas for river‐line and flash flood hazard and its mitigation through GIS Database Management System (DBMS) of geo‐hydrometeorological parameters. The Dabka watershed constitutes a part of the Kosi Basin in the Lesser Himalaya, India in district Nainital has been selected for the case illustration.

The Dabka DBMS is constituted of three GIS (Geographic Information System) modules, i.e. geo‐informatics (consists of geomorphology, soils, geology and land use pattern, slope analysis, drainage density and drainage frequency), weather informatics (consists of daily, monthly and annual weather data about temperature, rainfall, humidity and evaporation) and hydro‐informatics (consist of runoff, sediment delivery, and denudation). The geo‐informatics and weather informatics modules carried out by comprehensive field work and GIS mapping than both modules used to carry out hydro‐informatics module. Through the integration and superimposing of spatial data and attribute data with their GIS layers of all these modules prepared Flood Hazard Index (FHI) to identify the level of vulnerability for flood hazards and their socio‐economic and environmental risks.

The results suggest that geo‐environmentally most stressed areas of barren land (i.e. river‐beds, flood plain, denudational hills, sites of debris flow, gullies, landslide prone areas etc.) have extreme vulnerability for flood hazard due to high rate of runoff, sediment load delivery and denudation during rainy season (i.e. respectively 84.56 l/s/km², 78.60 t/km² and 1.21 mm/year) whereas in geo‐environmentally least stressed dense forest areas (i.e. oak, pine and mixed forests) have low vulnerability due to low rate of stream runoff, sediment load delivery and denudation (i.e. respectively 20.67 l/s/km², 19.50 t/km² and 0.20 mm/year). The other frazzled geo‐environment which also found high vulnerable for flood hazard and their risks is agricultural land areas due to high rate of stream runoff, sediment load delivery and denudation rates (i.e. respectively 53.15 l/s/km², 90.00 t/km² and 0.92 mm/year).

For hydro‐informatics module it is quite difficult to monitor water and sediment discharge data from each and every stream of the Himalayan terrain due the steep and rugged topography. It requires strategic planning and trained man power as well as sufficient funds; therefore representative micro‐watershed approach of varied ecosystem followed for a three years (2006‐2008) period.

The study will have great scientific relevance in the field of river‐line flood and flash flood hazard and its socio‐economic and environmental risks prevention and management in Himalaya and other mountainous terrain of the world.

This study generated primary data on hydro‐informatics and weather informatics to integrate with geo‐informatics data for flood hazard assessment and mitigation as constitutes a part of multidisciplinary project, Department of Science and Technology (D.S.T.) Government of India.

Cambodia is considered one of the countries that are most vulnerable to adverse effects of climate change, particularly floods and droughts. Kampong Speu Province is a frequent site of calamitous flash floods. Reliable sources of flash flood information and analysis are critical in efforts to minimize the impact of flooding. Unfortunately, Cambodia does not yet have a comprehensive program for flash flood hazard mapping, with many places such as Kampong Speu Province having no such information resources available. The purpose of this paper is, therefore, to determine flash flood hazard levels across all of Kampong Speu Province using analytical hierarchy process (AHP) and geographical information system (GIS) with satellite information.

The integrated AHP–GIS analysis in this study encompasses ten parameters in the assessment of flash flood hazard levels across the province: rainfall, geology, soil, elevation, slope, stream order, flow direction, distance from drainage, drainage density and land use. The study uses a 10 × 10 pairwise matrix in AHP to compare the relative importance of each parameter and find each parameter’s weight. Finally, a flash flood hazard map is developed displaying all areas of Kampong Speu Province classified into five levels, with Level 5 being the most hazardous.

This study reveals that high and very high flash flood hazard levels are identified in the northwest part of Kampong Speu Province, particularly in Aoral, Phnum Srouch and Thpong districts and along Prek Thnot River and streams.

The flash flood hazard map developed here provides a wealth of information that can be invaluable for implementing effective disaster mitigation, improving disaster preparedness and optimizing land use.

Natural hazards such as floods, wildfires and droughts disrupt communities, their economies and environments, and cost millions every year. The existing literature on hazard mitigation shows that community resilience is best achieved when mitigation strategies are integrated with land use and comprehensive planning. The purpose of this paper is to evaluate the strengths and weaknesses of hazard mitigation in local comprehensive plans.

The analysis uses a new plan evaluation protocol that integrates flood, wildfire and drought mitigation to evaluate the plans of the six largest and fastest growing counties in Arizona.

The study finds that counties do not plan equally well for all hazards, that they tend to plan better for droughts than wildfires and floods, and indicates the need to improve hazard information in plans to support the adoption of mitigation goals, objectives and strategies.

The research is based on a small sample of comprehensive plans. It focuses on the content of plans rather than the causes that may explain this content or the implementation of the strategies included in the plans. Future research will thus need to analyze larger numbers of plans to identify the determinants of the degree to which comprehensive plans integrate hazard mitigation; and evaluate whether strategies advanced in plans are integrated with other planning documents and implemented.

The paper makes recommendations to improve the plans evaluated and to guide planners as they develop or revise comprehensive plans in other jurisdictions subject to natural hazards.

The key methodological contribution of the paper is the new plan evaluation protocol designed to assess the wildfire, drought and flood mitigation provisions in comprehensive plans.

Climate change, deforestation and hydropower dams are contributing to environmental change in the Lower Mekong River region, the combined effects of which are felt by many rural Cambodians. How people perceive and manage the effects of environmental change will influence future adaptation strategies. The objective of this research was to investigate whether the use of a low-cost, explicitly spatial method (participatory mapping) can help identify locally relevant opportunities and challenges to climate change adaptation in small, flood-prone communities. Four villages along the banks of the Mekong River in Kratie Province, Cambodia, were the subject of this research. To identify perceived environmental hazards and adaptive responses, eight workshops were conducted using focus-group interviews and participatory mapping. The communities’ responses highlight the evolving nature of environmental hazards, as droughts increase in perceived importance while the patterns of wet season flooding were also perceived to be changing. The attribution of the drivers of these hazards was strongly skewed towards local factors such as deforestation and less towards regional or global drivers affecting the hydrology of the Mekong and climate patterns. Combining participatory mapping with focus-group interviews allowed a greater depth of understanding of the vulnerabilities and opportunities available to communities than reliance on a single qualitative method. The study highlights the potential for a bottom-up transfer of information to strengthen existing climate change policies and tailor adaptation plans to local conditions.

Vulnerability studies are commonly used to inform planning, as cities and regions seek to build resilience to environmental hazards. In Shelby County, Tennessee, socioeconomic census tract data were mapped to identify the socially vulnerable population and places to underpin strategies in the Mid-South Regional Resilience Master Plan (RRMP). While this is an important step in identifying vulnerability in the county, this paper aims to enhance the local analysis through an integrated approach that considers both social factors and environmental hazards in assessing vulnerability.

This paper conducts a social vulnerability assessment by integrating a social vulnerability index with risk exposure analysis at the census tract level to identify the population and places vulnerable to riverine flooding in Shelby County.

The analysis reveals that social vulnerability assessments that do not relate socioeconomic factors to specific environmental hazards such as riverine flooding underestimate the population and places that are vulnerable. For Shelby County, this has the tendency to undermine the prioritization and effectiveness of strategies to build resilience to riverine flooding and can worsen preexisting marginalization.

This paper recommends integrated vulnerability assessments for each of the environmental hazards identified in the Mid-South RRMP to augment existing resilience efforts in the county.

This paper enhances the understanding of social vulnerability assessments by consolidating the need for integrated assessment frameworks as basis for resiliency planning.