This paper describes the design and application of a benefit-cost model to the city of Durban’s (South Africa) climate change adaptation options. The approach addresses the inability to compile an accurate damage-cost function for economic prioritizations at the local level. It proposes that uncertainty over climate impacts and the efficacy of adaptation responses, in conjunction with the lack of economic data, high levels of economic informality and inequality make it difficult to link adaptation efforts to positive GDP impact in Durban. Instead, the research based its calculations of “benefits” on the number of people impacted and the extent of the welfare benefits imparted by the respective adaptation efforts. It also took into account the uncertainty over future events, capacity constraints, priorities of decision makers and the risk of maladaptation. The results were reported as benefit-cost ratios for 16 clusters of interventions (many of which were primarily the responsibility of one municipal department or agency) in each of four future scenarios (defined by minor or major climate change and weak or strong socio-institutional capacity). The paper presents and discusses the benefit-cost ratios and total benefits for each of the intervention clusters in each of the future scenarios. It emphasizes how these are influenced by choices of time frames. It also highlights how the most efficient interventions across all futures and time frames tend to be socio-institutional – for instance the creation of a cross-sectoral disaster management forum, sea level rise preparedness and early warning system, and creating climate change adaptation capacity within the water services unit. Ecosystem-based adaptation measures had moderate benefit-cost ratios, probably because in Durban the land that needs to be purchased for this is relatively expensive. Infrastructure-based clusters generally had the lowest benefit-cost ratios.
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Due to their prevalence in developing countries and the range of ecosystem services they provide, projects aimed at promoting mangroves align with several of the UN Sustainable Development Goals—specifically Goals 13, 14, and 15—which concern adaptation to climate change and the sustainable management of forest and coastal resources. Although mangroves themselves are sensitive to climate change, they also provide services that would help reduce damages, by sequestering carbon, enhancing coastline stability, and protecting coastal settlements from tropical storm surges. In particular, mangroves can rapidly colonize and stabilize intertidal sediments, promoting coastal accretion to reduce the impact of sea level rise. The Government of Bangladesh has established mangrove plantations with the intent to accelerate accretion and stabilize 120,000ha of coastland. As a case study, this paper uses GIS data on coastal dynamics and land cover to evaluate the effectiveness of mangrove plantations for facilitating accretion and preventing erosion in Bangladesh. The results indicate that plantation areas experience greater rates of accretion relative to erosion than non-plantation areas, confirming that mangroves have an important role to play in the sustainable development of coastal regions.
Flooding is a very costly natural hazard in the UK and is expected to increase further under future climate change scenarios. Flood defences are commonly deployed to protect communities and property from flooding, but in recent years flood management policy has looked towards solutions that seek to mitigate flood risk at flood-prone sites through targeted interventions throughout the catchment, sometimes using techniques which involve working with natural processes. This paper describes a project to provide a succinct summary of the natural science evidence base concerning the effectiveness of catchment-based ‘natural’ flood management in the UK. The evidence summary is designed to be read by an informed but not technically specialist audience. Each evidence statement is placed into one of four categories describing the nature of the underlying information. The evidence summary forms the appendix to this paper and an annotated bibliography is provided in the electronic supplementary material.
Efforts to ameliorate flooding have historically centred on engineered solutions such as dredging rivers, building levees, and constructing spillways. The potential for ecosystem-based adaptation (EbA) options is becoming increasingly apparent; however, implementation is often limited by a poor understanding of their costs and benefits. This study compares the costs and benefits of a range of hard infrastructure and ecosystem-based adaptation options to mitigate flooding under climate change using data from two catchments in Fiji. We employ unique survey data to document the costs of flooding under various climate change scenarios. We then use a hydrological model to simulate the potential benefits of a range of hard infrastructure and EbA options and conduct a comprehensive cost–benefit analysis. We find that under reasonable economic assumptions, planting riparian buffers is the most cost-effective option, yielding benefit–cost ratios between 2.8 and 21.6. However, the absolute level of protection provided by this strategy is low. Afforestation provides greater overall benefits, yielding net present values between 12.7 and 101.8 million Fijian dollars, although implementation costs would be substantial. Planting floodplains and reinforcing riverbanks provide some monetary benefits that are lower than riparian and upland planting. Elevating houses is not economically viable under any climate scenario.
Protection against coastal disasters has been identified as an important service of mangrove ecosystems. Empirical studies on this service have been criticized, however, for using small samples and inadequately controlling for confounding factors. We used data on several hundred villages to test the impact of mangroves on human deaths during a 1999 super cyclone that struck Orissa, India. We found that villages with wider mangroves between them and the coast experienced significantly fewer deaths than ones with narrower or no mangroves. This finding was robust to the inclusion of a wide range of other variables to our statistical model, including controls for the historical extent of mangroves. Although mangroves evidently saved fewer lives than an early warning issued by the government, the retention of remaining mangroves in Orissa is economically justified even without considering the many benefits they provide to human society besides storm-protection services.
Hurricanes Katrina and Rita showed the vulnerability of coastal communities and how human activities that caused deterioration of the Mississippi Deltaic Plain (MDP) exacerbated this vulnerability. The MDP formed by dynamic interactions between river and coast at various temporal and spatial scales, and human activity has reduced these interactions at all scales. Restoration efforts aim to re-establish this dynamic interaction, with emphasis on reconnecting the river to the deltaic plain. Science must guide MDP restoration, which will provide insights into delta restoration elsewhere and generally into coasts facing climate change in times of resource scarcity.
In many countries around the world impacts of climate change are assessed and adaptation options identified. We describe an approach for a qualitative and quantitative assessment of adaptation options to respond to climate change in the Netherlands. The study introduces an inventory and ranking of adaptation options based on stakeholder analysis and expert judgement, and presents some estimates of incremental costs and benefits. The qualitative assessment focuses on ranking and prioritisation of adaptation options. Options are selected and identified and discussed by stakeholders on the basis of a sectoral approach, and assessed with respect to their importance, urgency and other characteristics by experts. The preliminary quantitative assessment identifies incremental costs and benefits of adaptation options. Priority ranking based on a weighted sum of criteria reveals that in the Netherlands integrated nature and water management and risk based policies rank high, followed by policies aiming at ‘climate proof’ housing and infrastructure.
As in other parts of the world, the indigenous people of Jharkhand hold important context-relevant knowledge and strategies for addressing dwindling natural resources base and climate change. The paper documents some of the collective wealth of indigenous knowledge related to agricultural practices, including land preparation/ manuring/ soil treatment, cropping systems, input management, water resource management and utilization, and soil and water conservation practices, used especially by tribal farmers of the region. Related research and policy issues essential for successful amalgamation of such indigenous knowledge in resource conservation and climate change adaptation are also discussed. It concludes that the indigenous knowledge will help to address food and nutritional security in the face of climate change.
Ecosystem-based management (EBM) of forests is gaining acceptance for its focus on the maintenance of the long-term integrity of ecosystem processes, but climate change challenges this view because of its impacts on these very processes. We have therefore evaluated the robustness of EBM to projected climate change, considering the role of climate on forest growth and fire regime in a boreal forest of eastern Canada. A climate sensitive growth index model was calibrated for three commercial species and used to project the evolution of merchantable volume for two climate scenarios (B1 and A2) under conventional and EBM strategies. Current burn rate and burn rates under future climate scenarios were also considered. Under the most extreme projected climate scenario, the periodic timber supply could be reduced by up to 79% through direct (growth reduction) and indirect (fire) effects. However, ecological indicators show that EBM is a more robust forest management strategy than conventional one demonstrating its adaptation potential to climate change at least in the short term.
CSIR-National Environmental Engineering Research Institute (CSIR-NEERI) along with the United Nations Environment Programme (UNEP), Geneva, organized a consultative workshop on “Ecological Engineering for DRR (Disaster Risk Reduction) and CCA (Climate Change Adaptation)” in NEERI, Nagpur, on February 5, 2016. The workshop brought together technical experts and policy makers across India to review how the new opportunities offered by science and international policies could be leveraged to promote ecosystem-based (Eb) approaches in India. The consultation succeeded in brainstorming and identifying key actions, actors, and priority areas keeping in view conservation and development challenges. Discussions were also on implementation strategies, monitoring and evaluation mechanisms. Workshop also came up with integrating biodiversity management with existing and ongoing development practices, including existing policy measures and enabling mechanisms at regional, national, and state level. Priority actions for improving DRR approaches, and identification of interventions to support EbDRR and EbA in the country, and possible role and responsibility of potential national institutions and other agencies were the final outcomes of the brainstorming and workshop.
Our estimation results confirm the role of biodiversity as a nature-based policy solution for climate change mitigation, shedding light on the policy actions that generate co-benefits by enhancing ecosystems’ capacity to mitigate climate change impacts, while conserving biodiversity and sustaining the flows of EGS for human livelihoods. Especially, nature-based mitigation policies are more cost-effective and better at coping with the ethic and inequality issues associated with distributional impacts of the policy actions, compared to the pure technical solutions to improving energy efficiency and reducing emissions. However, the strength of biodiversity as a nature-based policy option for climate change mitigation depends on both the nature of the EGS and the geographical area under consideration. Our estimation results confirm the role of biodiversity as a nature-based policy solution for climate change mitigation, shedding light on the policy actions that generate co-benefits by enhancing ecosystems’ capacity to mitigate climate change impacts, while conserving biodiversity and sustaining the flows of EGS for human livelihoods. Especially, nature-based mitigation policies are more cost-effective and better at coping with the ethic and inequality issues associated with distributional impacts of the policy actions, compared to the pure technical solutions to improving energy efficiency and reducing emissions. However, the strength of biodiversity as a nature-based policy option for climate change mitigation depends on both the nature of the EGS and the geographical area under consideration.
Forests play a major role In Earth’s carbon cycle through assimilation, storage, and emission of CO2. Establishment and management of boreal, temperate, and tropical forest and agroforest systems could potentially enhance sequestration of carbon in the terrestrial biosphere. A biological and economic analysis of forest establishment and management options from 94 nations revealed that forestation, agroforestry, and silviculture could be employed to conserve and sequester one Petagram (Pg) of carbon annually over a 50-year period. The marginal cost of implementing these options to sequester 55 Pg of carbon would be approximately $10/Mg.
“Ecological Infrastructure (EI)” are defined as naturally functioning ecosystems that deliver valuable services to people, such as healthy mountain catchments, rivers, wetlands, coastal dunes, and nodes and corridors of natural habitat, which together form a network of interconnected structural elements in the landscape. On the other hand, natural disaster occur at the locations where habitat was reduced due to the changes of land use, in which the land was converted to the settlements and agricultural cropland. Hence, habitat loss and natural disaster are linked closely. Ecological infrastructure is the nature-based equivalent of built or hard infrastructure, and is as important for providing services and underpinning socio-economic development. Hence, ecological infrastructure is expected to contribute to functioning as ecological disaster reduction, which is termed Ecosystem-based Solutions for Disaster Risk Reduction (Eco-DRR). Although ecological infrastructure already exists in the landscape, it might be degraded, needs to be maintained and managed, and in some cases restored. Maintenance and restoration of ecological infrastructure is important for security of human lives. Therefore, analytical tool and effective visualization tool in spatially explicit way for the past natural disaster and future prediction of natural disaster in relation to ecological infrastructure is considered helpful. Hence, Web-GIS based Ecological Infrastructure Environmental Information System (EI-EIS) has been developed. This paper aims to describe the procedure of development and future application of EI-EIS. The purpose of the EI-EIS is to evaluate functions of Eco-DRR. In order to analyse disaster data, collection of past disaster information, and disaster-prone area is effective. First, a number of digital maps and analogue maps in Japan and Europe were collected. In total, 18,572 maps over 100 years were collected. The Japanese data includes Future-Pop Data Series (1,736 maps), JMC dataset 50m grid (elevation) (13,071 maps), Old Edition Maps: Topographic Map (325 maps), Digital Base Map at a scale of 2500 for reconstruction planning (808 maps), Detailed Digital Land Use Information for Metropolitan Area (10 m land use) (2,436 maps), and Digital Information by GSI (national large scale map) (71 maps). Old Edition Maps: Topographic Map were analogue maps, and were scanned and georeferenced. These geographical area covered 1) Tohoku area, 2) Five Lakes of Mikata area (Fukui), 3) Ooshima Island (Tokyo), 4) Hiroshima area (Hiroshima), 5) Okushiri Island (Hokkaido), and 6) Toyooka City area (Hyogo). The European data includes topographic map in Germany (8 maps), old topographic map in Germany (31 maps), ancient map in Germany (23 maps), topographic map in Austria (9 maps), old topographic map in Austria (17 maps), and ancient map in Austria (37 maps). Second, focusing on Five Lakes of Mikata area as an example, these maps were integrated into the ArcGIS Online (R) (ESRI). These data can be overlaid, and time-series data can be visualized by a time slider function of ArcGIS Online.
Landslide hazard can be influenced by natural resource management and rural development related activities, such as forest management, road construction, agricultural practices and river management. Vegetation cover and its utilizations may play a role in mitigating the risk of landsliding. Moreover and above all, it does play a role in mitigating the processes leading to increased landslide hazard, such as gully erosion. Thus, forest management and development are of particular concern. But all people living in mountain areas rely on the soil stability for their livelihoods, and their livelihoods may influence this soil stability. Therefore all related activities have to be done on an appropriate way in order to promote soil and slope stability. To identify best adapted practices in a particular area, to organize spatially the different land uses and to promote the implementation of the identified best practices, the ideal scale is the watershed. It allows addressing upstream-downstream linking issues, such as landslides, and provides a framework for sound land use planning. However, it is not always possible to implement actions exactly with the watershed boundaries. From the lack of knowledge regarding the scientific evidence of the role of forests against landslides to the institutional challenge of implementing watershed scaled policies, many progresses have to be done regarding this issue. But the already existing scientific knowledge, the integrated projects which are already implemented and the results which are obtained are encouraging. Above all, they show that fundamental research, socio-economic levers and institutional development have to be carried out and developed in a sound way, towards a better understanding of all the natural and man-made processes and a better management of all natural resources, in particular water and soil of the mountain areas.
Ecosystem-based approaches for adaptation (EbA) integrate the use of biodiversity and ecosystem services into an overall strategy for helping people adapt to climate change. To date, however, insight into these approaches has often been based on anecdotal case studies of local peoples’ use of ecosystems. A systematic map of ecosystem-based adaptation-relevant peer-reviewed literature, and a sample of grey literature, was undertaken to (1) give a methodical overview of the state of the evidence-base on ecosystem-based adaptation effectiveness and (2) identify key knowledge gaps. A framework was developed with stakeholders to assess the evidence-base for ecosystem-based adaptation effectiveness. The literature reviewed showed that much can be learnt about ecosystem-based adaptation from articles which considered climatic variability and climate extremes. Measures of the effectiveness of ecosystem-based adaptation-relevant interventions recorded in the articles showed positive results, although discussion of thresholds, limits and timescales related to these interventions was limited. Social, environmental and economic benefits of ecosystem-based adaptation interventions were in evidence in most articles, and though costs were discussed, this was limited in extent. It is concluded that the literature on ecosystem-based adaptation-relevant interventions addressing climatic variability, change, and linked extremes and natural hazards, contains some information that will support making the case for ecosystem-based adaptation, but the evidence-base has a number of gaps that should be addressed.
Marine vegetated habitats (seagrasses, salt-marshes, macroalgae and mangroves) occupy 0.2% of the ocean surface, but contribute 50% of carbon burial in marine sediments. Their canopies dissipate wave energy and high burial rates raise the seafloor, buffering the impacts of rising sea level and wave action that are associated with climate change. The loss of a third of the global cover of these ecosystems involves a loss of CO2 sinks and the emission of 1 Pg CO2 annually. The conservation, restoration and use of vegetated coastal habitats in eco-engineering solutions for coastal protection provide a promising strategy, delivering significant capacity for climate change mitigation and adaption.
Results of recent investigations suggest that climate change tends to accelerate geodisasters. Therefore, adaptation to climate change has rapidly become and urgent issue. In comparison to those examining water disasters, few studies have examined climate change-induced geodisasters. This study aims to focus on climate change-induced geodisasters in various countries of the Asia-Pacific region, especially in Japan and Vietnam. Sea level rise is accounted for about 2 mm/1 on average in the region. This amount is much larger in some places due to groundwater extraction. Moreover, we should prepare for the worst case in which climate-induced severe rainfall, wave attacks, storm surges and a great earthquake might take place simultaneously or almost simultaneously with each other in the coastal zone, although this worst case might be very rare. As a possible compound geohazard caused by climate change, we propose solutions with emphasizes on using geosynthetics and ecological engineering measures.
Among the effects of global warming, sea level rise (SLR) and severe typhoons pose the greatest threat to the stability of human settlements along coastlines. Therefore, counter measures must be developed to mitigate the influences of strong typhoons and persistent SLR for coastal protection. This study assesses climate change impacts on coastal erosion, especially in two projected SLR scenarios of RCP2.6 and RCP8.5. The results show that SLR and severe typhoons lead to the increase of coastal erosion, beach lowering and scour. Moreover, as in projected SLR scenarios, average waves in high tide can cause severe soil erosion at inner slopes and lead to dyke failure by 2060. The paper highlights the need for additional countermeasures to protect the coast of Hai Hau district against SLR and severe typhoons. Among the alternatives available for countering these threats, applying soil stabilization and soil improvement combined with geosynthetics are promising strategies for coastal structures. Hybrid structures can be used with earth reinforcement and soil improvement. Additionally, the paper emphasizes the importance of multiple protective adaptations, including geosynthetics and ecological engineering measures against climate change-induced severe erosion on the coast of Hai Hau district.
Conversion of the Danube river floodplains through dyke construction for farming and other development has cut off 95, 75 and 28% of the floodplains of the upper Danube, the lower Danube and the Danube delta, respectively. Together with channelization, this has exacerbated flood peaks. Anthropogenic climate change is anticipated to bring more frequent flooding and reduced water quality. In assessing ongoing floodplain restoration work that commenced in 1993, this paper finds the following. (a) Along the lower Danube River, restoration of floodplains by decommissioning under-performing flood protection infrastructure has provided many benefits. The benefits of these adaptation measures include improved natural capacity to retain and release floodwaters and remove pollutants, enhanced biodiversity, and strengthened local economies through diversification of livelihoods based on natural resources. (b) The drivers for more successful adaptation measures in the Danube included EU expansion, legal mechanisms, and local desire to improve livelihoods. The support of non-governmental organizations (WWF and partner organizations) for basin- and regional-level planning for more effective water resource management has also been a powerful driver of policy change in the lower Danube countries.
Greening roofs or walls to cool down city areas during summer, to capture storm water, to abate pollution, and to increase human well-being while enhancing biodiversity: nature-based solutions (NBS) refer to the sustainable management and use of nature for tackling societal challenges. Building on and complementing traditional biodiversity conservation and management strategies, NBS integrate science, policy, and practice and create biodiversity benefits in terms of diverse, well-managed ecosystems.
Even though ‘green’ options for addressing the impacts of climate change have gained in currency over recent years, they are yet to be fully mainstreamed into development policy and practice. One important reason is the lack of economic evidence as to why investing in ecosystems offers a cost-effective, equitable and sustainable means of securing climate adaptation, disaster risk reduction and other development co-benefits. This chapter presents a conceptual framework for integrating ecosystem values into climate-compatible development planning. Case studies from coastal areas of Kenya and Sri Lanka illustrate how such an approach can be applied in practice to make the economic and business case for ecosystem-based measures. It is argued that, rather than posing ‘grey’ and ‘green’ options as being necessarily in opposition to each other or as mutually incompatible, from an economic perspective both should be seen as being part and parcel of the same basic infrastructure that is required to deliver essential development services in the face of climate change
A central claim of community-based adaptation (CBA) is that it increases resilience. Yet, the concept of resilience is treated inconsistently in CBA, obscuring discussion of the limitations and benefits of resilience thinking and undermining evaluation of resilience outcomes in target communities. This paper examines different participatory assessment activities carried out as part of CBA case studies in Timor-Leste and Solomon Islands. The activities and their outputs were assessed against 10 characteristics of resilience previously identified in a systematic review. The findings offer support to the claim that CBA can build resilience in target communities, revealing the inherent strengths of CBA in relation to resilience. However, it is necessary for CBA assessments to simultaneously incorporate activities that consider cultural, political, economic and ecological factors influencing resilience within and between communities. This may demand multiple staff with different skills. The findings also highlight the importance of politics and power in shaping adaptive capacity. In particular, addressing the highly context specific nature of social, cultural and political relations demands an approach that is situated in and responsive to local realities. Overall, our case studies suggest that using the 10 characteristics as an analytical framework offers support to practitioners looking to develop, implement or evaluate CBA assessment activities. Yet within this, it is critical that a focus on increasing resilience through CBA does not preclude transformation in social relations. Realising the potential to support resilience and transformation requires CBA practitioners to acknowledge the multifaceted nature of resilience, whilst also paying close attention to multiple potential barriers to equitable adaptation.
This chapter seeks to articulate future directions in the field of Eco-DRR/CCA, in the context of the new post-2015 sustainable development agenda. It synthesises the experiences featured in this book and highlights the key challenges and opportunities in advancing Eco-DRR/CCA approaches. Four main themes are discussed: demonstrating the economic evidence of Eco-DRR/CCA; decision-making tools for Eco-DRR/CCA; innovative institutional arrangements and policies for mainstreaming Eco-DRR/CCA; and research gaps. The major global policy agreements in 2015 are examined for their relevance in promoting Eco-DRR/CCA implementation in countries. Finally, the authors reflect on a new agenda for Eco-DRR/CCA and outline some of the key elements required to significantly advance and scale-up Eco DRR/CCA implementation globally.
In Mexico, due to reduced and unevenly distributed hydrological resources and incipient water management capabilities, climate change adaptation in the water sector is recognized as an urgent issue. To derive lessons for climate change adaptation, this paper evaluates the results gained after five years of an integrated river basin management (IRBM) programme in the Conchos River in northern Mexico. Autonomous adaptation measures assessed include: modernization of irrigation practices; pilot sustainable watershed management projects in the upper basin; development of an environmental flow assessment and a proposal to improve water allocation; and the creation of the Inter-institutional Working Group as a basin organization. These measures have improved river basin management, yet adverse outcomes were also observed, such as impacts of surface water efficiency measures that were not managed in conjunction with groundwater. Key adaptation lessons derived include: the importance of multi-stakeholder participation in designing and implementing adaptive management measures; the need for significant investment in transfer of expertise and capacity building; and the positive effect of linking local, national and international institutions. These results highlight the need for more investment in ‘soft’ adaptive management in place of infrastructure. In the Rio Conchos, if these ‘no regrets’ adaptation measures are consolidated in the following years, they will serve as a foundation to develop planned and more effective climate change adaptation programmes, and enhance institutional, environmental and societal resilience.
Much of the developing world and areas of the developed world suffer water vulnerability. Engineering solutions enable technically efficient extraction and diversion of water towards areas of demand but, without rebalancing resource regeneration, can generate multiple adverse ecological and human consequences. The Banas River, Rajasthan (India), has been extensively developed for water diversion, particularly from the Bisalpur Dam from which water is appropriated by powerful urban constituencies dispossessing local people. Coincidentally, abandonment of traditional management, including groundwater recharge practices, is leading to increasingly receding and contaminated groundwater. This creates linked vulnerabilities for rural communities, irrigation schemes, urban users, dependent ecosystems and the multiple ecosystem services that they provide, compounded by climate change and population growth. This paper addresses vulnerabilities created by fragmented policy measures between rural development, urban and irrigation water supply and downstream consequences for people and wildlife. Perpetuating narrowly technocentric approaches to resource exploitation is likely only to compound emerging problems. Alternatively, restoration or innovation of groundwater recharge practices, particularly in the upper catchment, can represent a proven, ecosystem-based approach to resource regeneration with linked beneficial socio-ecological benefits. Hybridising an ecosystem-based approach with engineered methods can simultaneously increase the security of rural livelihoods, piped urban and irrigation supplies, and the vitality of river ecosystems and their services to beneficiaries. A renewed policy focus on local-scale water recharge practices balancing water extraction technologies is consistent with emerging Rajasthani policies, particularly Jal Swavlamban Abhiyan (‘water self-reliance mission’). Policy reform emphasising recharge can contribute to water security and yield socio-economic outcomes through a systemic understanding of how the water system functions, and by connecting goals and budgets across multiple, currently fragmented policy areas. The underpinning principles of this necessary paradigm shift are proven and have wider geographic relevance, though context-specific research is required to underpin robust policy and practical implementation.