How do local communities adapt to climate changes along heavily damaged coasts? A Stakeholder Delphi study in Ky Anh (Central Vietnam)

The Central Vietnamese coast faces increasing impacts on the local livelihoods of coastal communities as a result of the increasing natural hazards which include tropical storms, heavy rains, and floods. A challenge for the local populations is improving their adaptation capacity to climate change hazards in a sustainable way. This study deals with the impacts of climate change-associated hazards and adaptation capacity in coastal communes of the Ky Anh district, Ha Tinh province along the coast in Central Vietnam. A combination of the Stakeholder Delphi technique and the DPSIR (drivers–pressures–states–impacts–responses) framework was used. Delphi questionnaires allowed assessing the consensus among the respondents of a stakeholder group. Twenty questions and 20 statements were listed reflecting the DPSIR components. Thirty-six panel members, which were randomly selected from four stakeholder groups which included local authorities, farmers, fishermen, and fish traders, were involved in a two-round Delphi process. The results show that, both agricultural and non-agricultural sectors are main drivers (D); migration, calamities, population growth, mineral mining, aquaculture processing, and agriculture are main pressures (P); changes in the frequency of extreme weather events, increasing intensity of storms, floods, and droughts indicate main states (S); changes in agricultural land use and productivity are main impacts (I); construction of and upgrading dykes and irrigation systems should be the principal responses (R) in the vision of the local stakeholders. The Kendall’s W value for the second round is 0.681, indicating a high degree of consensus among the panel members and confidence in the ranks. Overall, the study advocates developing sustainable ecosystems, an upgraded New Rural Planning, and renewable energy strategies as the main local adaptations to climate change hazards in this area.     

The Gathering Storm: managing adaptation to environmental change in coastal communities and small islands

Small island communities are inherently coastal communities, sharing many of the attributes and challenges faced by cities, towns and villages situated on the shores of larger islands and continents. In the context of rapidly changing climates, all coastal communities are challenged by their exposure to changing sea levels, to increasingly frequent and severe storms, and to the cumulative effects of higher storm surges. Across the globe, small island developing states, and small islands in larger states, are part of a distinctive set of stakeholders threatened, not only by climate change but also by shifting social, economic, and cultural conditions. C-Change is a collaborative International Community–University Research Alliance (ICURA) project whose goal is to assist participating coastal communities in Canada and the Caribbean region to share experiences and tools that aid adaptation to changes in their physical environment, including sea-level rise and the increasing frequency of extreme weather events associated with climate change. C-Change researchers have been working with eight partner communities to identify threats, vulnerabilities, and risks, to improve understanding of the ramifications of climate change to local conditions and local assets, and to increase capacity for planning for adaptation to their changing world. This paper reports on the knowledge gained and shared and the challenges to date in this ongoing collaboration between science and society.     

Physical basis of coastal adaptation on tropical small islands

Small tropical islands are widely recognized as having high exposure and vulnerability to climate change and other natural hazards. Ocean warming and acidification, changing storm patterns and intensity, and accelerated sea-level rise pose challenges that compound the intrinsic vulnerability of small, remote, island communities. Sustainable development requires robust guidance on the risks associated with natural hazards and climate change, including the potential for island coasts and reefs to keep pace with rising sea levels. Here we review these issues with special attention to their implications for climate-change vulnerability, adaptation, and disaster risk reduction in various island settings. We present new projections for 2010–2100 local sea-level rise (SLR) at 18 island sites, incorporating crustal motion and gravitational fingerprinting, for a range of Intergovernmental Panel on Climate Change global projections and a semi-empirical model. Projected 90-year SLR for the upper limit A1FI scenario with enhanced glacier drawdown ranges from 0.56 to 1.01 m for islands with a measured range of vertical motion from ?0.29 to +0.10 m. We classify tropical small islands into four broad groups comprising continental fragments, volcanic islands, near-atolls and atolls, and high carbonate islands including raised atolls. Because exposure to coastal forcing and hazards varies with island form, this provides a framework for consideration of vulnerability and adaptation strategies. Nevertheless, appropriate measures to adjust for climate change and to mitigate disaster risk depend on a place-based understanding of island landscapes and of processes operating in the coastal biophysical system of individual islands.     

A framework for understanding climate change impacts on coral reef social–ecological systems

Corals and coral-associated species are highly vulnerable to the emerging effects of global climate change. The widespread degradation of coral reefs, which will be accelerated by climate change, jeopardizes the goods and services that tropical nations derive from reef ecosystems. However, climate change impacts to reef social–ecological systems can also be bi-directional. For example, some climate impacts, such as storms and sea level rise, can directly impact societies, with repercussions for how they interact with the environment. This study identifies the multiple impact pathways within coral reef social–ecological systems arising from four key climatic drivers: increased sea surface temperature, severe tropical storms, sea level rise and ocean acidification. We develop a novel framework for investigating climate change impacts in social–ecological systems, which helps to highlight the diverse impacts that must be considered in order to develop a more complete understanding of the impacts of climate change, as well as developing appropriate management actions to mitigate climate change impacts on coral reef and people.     

Regimes of human and climate impacts on coastal changes in Vietnam

Vietnam is a tropical to subtropical country located on the eastern Asian coast where the Red (Song Hong) and Mekong rivers discharge into the sea. The catchments of these two transboundary rivers cover parts of six countries, and their water and sediment discharges greatly influence the coastal seas of Vietnam. The impact of human activities include changes in the supply and distribution of water, sediments, and nutrients; changes in the relationships and balance among dynamically interacting factors and processes; and changes in the quality of the coastal and marine environments due to the increased use and accumulation of pollutants and the loss of habitats. These impacts have resulted in increasing unpredictability and severity of coastal problems such as floods, erosion, sedimentation, and saltwater intrusion; environmental pollution; and the degradation of ecosystems, with accompanying decrease in biodiversity and fishery productivity.     

Coastal vulnerability assessment of the predicted sea level rise in the coastal zone of Krishna–Godavari delta region,Andhra Pradesh,east coast of India

The Krishna–Godavari coastal region in east coast of India has a 525.15-km-long coastline with low-lying tidal mudflats, beaches, mangrove swamp, creek and tidal channels. Recently, the increasing frequency of tropical cyclones in the Bay of Bengal, i.e., Phylin and Hudhud in Andhra Pradesh coast, and the devastating impact of the 2004 tsunami in India increased the significance in assessing the vulnerability of the coastal lands to inundation and flooding, notably in the context of climate change-induced sea level rise. This study aims to estimate a coastal vulnerability index (CVI) for the coastal subregion of Krishna–Godavari delta and to use the calculated index to evaluate the vulnerability of 14 coastal talukas of the Krishna–Godavari delta region. This CVI is calculated by using four geological and three physical parameters characterizing the vulnerability of the study coastal region, including regional slope, coastal elevation, geomorphology, significant wave height, mean tidal range and relative sea level using different conventional and remotely sensed data. Using a composite coastal vulnerability index based on the relative risk rating of those parameters, each of the 14 coastal talukas was classified according to their vulnerability. The CVI results depict that coasts are least and most vulnerable to inundation, flooding and erosion of coastal lands where geological parameters are more efficient to CVI. The paper alerts to decision makers and planners to mitigate the natural disaster and manage the coastal zone and is a primary step toward prioritizing coastal lands for climate change adaptation strategies in the view of increased storminess and projected sea level rise.     

Spatiotemporal changes of geomorphic environment in the Muriganga–Saptamukhi estuarine interfluve of Indian Sundarban in the context of climate change: a case study

The surface of the earth has been continuously sculptured by the exogenetic processes primarily by the climatic hydrological attributes. Over the sequential phases of evolution of earth, the climatic attributes have altered. The alternative processes such as glaciation and declaciation, fluctuations of sea level and variability in rainfall pattern have changed the surface configuration through maneuvering the operations of the geographical processes. The issue of climate change has become a matter of scientific concern all over the world as the human communities are facing severe problems manifested in the form of flood, drought and submergence of low-lying coastal regions, estuaries and deltas. The present study is an attempt to understand the nature and extent of climate change (1890–2012) and related sea level rise (1970s–2010) in the deltaic Sundarban region of India since the last century and how far they are impacting the erosion–depositional processes (1925, 1926–2014). The changing trend of mean annual temperature, rainfall pattern and frequencies of tropical cyclones has been studied in detail, and spatiotemporal changes of geomorphic environment in different reaches of the study area have also been monitored with available multi-temporal geospatial data. The observation reveals that the flat sandy coastal belt and low-lying island in the extreme southern part have been severely affected by wave dash and seasonal storm surges which are mostly responsible for vigorous erosion. On the other hand, high tidal velocity is observed along the exposed concave bank in the upper–middle reaches of the Muriganga estuary and exposed outer bank in lower–middle reaches of Saptamukhi estuary. The thalweg line, which is very close to the river bank in those reaches of estuary, intensifies the hydraulic pressure along marginal parts of river bank which leads to erosion. Depositional activities are mostly observed along the sheltered inner reaches and convex river banks of the estuaries due to less effective tidal rushes, shallow channel depth, marginal flow velocity and gentle channel slope. Therefore, erosional and depositional processes cannot be explain by the relative mean sea level rise, because increasing mean sea level will affect the erosional processes uniformly in the entire estuary. In this present study area, both the erosional and depositional processes are simultaneously active depending on geographical exposure, sinuous channel pattern, channel depth and lithological compositions.     

Planned retreat as a management response to coastal risk: a case study from the Fleurieu Peninsula, South Australia

Australian coastal areas have been identified as highly vulnerable to climate change, with major projected impacts including sea level rise, extreme weather events, increased erosion, and a change in coastal processes and wave patterns. Such impacts would cause coastal settlements and ecosystems to face increasingly uncertain conditions. In response to increased risk, effective coastal management at local and regional scales is needed, with governing bodies providing significant leadership. This research explores the challenges of applying effective adaptation responses to projected climate change in vulnerable coastal systems on the South Coast of the Fleurieu Peninsula, South Australia. In particular, the option of planned retreat as a management response to coastal risk is critically examined, with the incorporation of learning from Byron Bay, NSW. A mixed methods approach was undertaken by integrating documentary interrogation with the analysis of interview responses from key coastal managers. It was determined that despite the increase in adaptation planning and development of management strategy options to manage sea level rise on the Fleurieu Peninsula, there is a lack of implementation of adaptation responses. In addition, planning seems to focus largely on the implications of sea level rise on infrastructure, often overlooking other risks and possible ecological impacts. Inconsistencies in governance are reflected at all levels, indicating a need for comprehensive improvements to ensure the incorporation of appropriate risk responses into planning decisions.     

Improving cross-sectoral climate change adaptation for coastal settlements: insights from South East Queensland,Australia

Climate change impacts affecting coastal areas, such as sea-level rise and storm surge events, are expected to have significant social, economic and environmental consequences worldwide. Ongoing population growth and development in highly urbanised coastal areas will exacerbate the predicted impacts on coastal settlements. Improving the adaptation potential of highly vulnerable coastal communities will require greater levels of planning and policy integration across sectors and scales. However, to date, there is little evidence in the literature which demonstrates how climate policy integration is being achieved. This paper contributes to this gap in knowledge by drawing on the example provided by the process of developing cross-sectoral climate change adaptation policies and programmes generated for three coastal settlement types as part of the South East Queensland Climate Adaptation Research Initiative (SEQCARI), a 3-year multi-sectoral study of climate change adaptation options for human settlements in South East Queensland, Australia. In doing so, we first investigate the benefits and challenges to cross-sectoral adaptation to address climate change broadly and in coastal areas. We then describe how cross-sectoral adaptation policies and programmes were generated and appraised involving the sectors of urban planning and management, coastal management, emergency management, human health and physical infrastructure as part of SEQCARI. The paper concludes by discussing key considerations that can inform the development and assessment of cross-sectoral climate change adaptation policies and programmes in highly urbanised coastal areas.     

Uncovering causes and effects of desertification using a Leopold matrix in Binh Thuan Province,Vietnam

Vietnam is a coastal country projected to be heavily affected by climate change.Binh Thuan Province is part of the driest region of Vietnam and is prone to desertification.An expert panel participated in developing a Leopold matrix which allowed for identification of desertification impact factors on the province's socioeconomic activities and assessment of the strength of cause-effect relationships in terms of magnitude and importance.Land use planning,surface water,and the length of the dry season are considered the most important causes,with the overall highest scores for both magnitude and importance in the cause-effect relationship.The largest effects of the different factors are perceived on water supply for agriculture and household use.Water availability and land use planning are important remedial action domains,while drought and land cover require monitoring to assess impacts.The indicators of cause and effect can be used in a longer-term general monitoring and assessment framework to combat desertification in the area.     

Coastal management, climate change adaptation and sustainability in small coastal communities: leatherback turtles and beach loss

Beaches are frequently subjected to erosion and accretion that are influenced by coastal development interventions and natural variations due to storms and changes in river flow. Climate change may also exacerbate beach erosion and accretion. Natural scientists are concerned with the sustainability of species dependent on the beach ecosystem. Policymakers are pre-occupied with the economic sustainability of coastal communities should species decline and prolonged beach loss occur. The aim of this paper is to explore the linkage between science and policy by reporting the findings of a study of coastal change impacts on leatherback turtle nesting and analysing the socio-economic and adaptation implications of these changes for coastal communities. Grande Riviere, Trinidad, was used as a case study. Primary fieldwork investigated unsustainable coastal management practices. A questionnaire was administered to examine livelihoods, including ecotourism based on leatherback turtle nesting, and knowledge and awareness of climate change. One key finding of the study was that the community’s livelihoods were natural resources dependent, and that natural beach dynamics and unsustainable coastal management practices posed major threats to natural resource and economic sustainability. Another key finding was that, despite these impacts, community knowledge and awareness of climate change in general was low, and there was a perception of state responsibility for climate change adaptation. The research findings have global applicability for coastal communities at risk of exposure and that are highly vulnerable to natural resources damage arising from anthropogenic stress and potential climate change. These communities require policy reforms to strengthen current coastal management practices and adaptation responses aimed at ensuring long-term sustainability.     

Influence of global warming on coastal infrastructural instability

The increasing infrastructure instability is an important issue in relation to the influences of global climate change in urban areas. A serious issue pertaining to this is the dual nature of damage triggered by events combined with climate change and natural hazards. For example, catastrophic damage could result from the combination of global warming with a great earthquake, which is a worst-case scenario. Although this worst-case scenario has rarely occurred and presents a low probability of occurrence, countermeasures must be prepared in advance based on an appropriate response and adaptation strategies. After an overview of possible infrastructural instabilities caused by global warming, methodologies are proposed placing emphasis on the increasing probability of infrastructural instability triggered by natural hazards resulting from groundwater-level (GWL) variations. These effects are expected to be particularly serious in coastal regions because of the influence of the rising sea level resulting from global warming. The influence of sea-level rises (SLR) will become apparent along with land subsidence because groundwater abstraction will become severe in coastal regions. Additionally, the probability of earthquake liquefaction increases if GWL rises in accompaniment with SLR. Using case histories, we examined the possible occurrence of these natural hazards as a result of global warming. Finally, possible countermeasures and adaptation strategies for reducing and mitigating infrastructure damage accelerated by global warming are described for each case in specific regions. In particular, special attention should be paid to adaptation strategies in coastal lowlands, which particularly suffer from the effects of land subsidence.     

Socio-economic vulnerability of the megacity of Shanghai (China) to sea-level rise and associated storm surges

Sea-level rise (SLR) poses a significant threat to many coastal areas and will likely have important impacts on socio-economic development in those regions. Located on the eastern coast in China, the megacity of Shanghai is particularly vulnerable to SLR and associated storm surge risks. Using the municipality of Shanghai as a case study, the possible impacts of flooding risks caused by SLR and associated storm surges on socio-economic development in the region were analysed by a Source–Pathway–Receptor–Consequence (SPRC) conceptual model. The projections of flooding risk in the study area were simulated by MIKE21 (a two-dimensional hydrodynamic model) for the three time periods of 2030, 2050 and 2100. An index system for vulnerability assessment was devised, in which flooding depth, density of population, GDP per capita, GDP per unit land, loss rate under flooding and fiscal revenue were selected as the key indicators. A quantitative spatial assessment method based on a GIS platform was established by quantifying each indicator, calculating and then grading the vulnerability index. The results showed that in the 2030 projection, 99.3 % of the areas show no vulnerability to SLR and associated storm surges under the present infrastructure. By 2050, the areas with low, moderate and high vulnerabilities change significantly to 5.3, 8.0 and 23.9 %, respectively, while by 2100, the equivalent figures are 12.9, 6.3 and 30.7 %. The application of the SPRC model, the methodology and the results from this study could assist with the objective and quantitative assessment of the socio-economic vulnerability of other similar coastal regions undergoing the impacts of SLR and associated storm surges. Based on the results of this study, mitigation and adaptation measures should be considered, which include the controlling the rate of land subsidence, the reinforcement of coastal defence systems and the introduction of adaptation in long-term urban planning.     

Population dynamics,delta vulnerability and environmental change: comparison of the Mekong,Ganges–Brahmaputra and Amazon delta regions

Tropical delta regions are at risk of multiple threats including relative sea level rise and human alterations, making them more and more vulnerable to extreme floods, storms, surges, salinity intrusion, and other hazards which could also increase in magnitude and frequency with a changing climate. Given the environmental vulnerability of tropical deltas, understanding the interlinkages between population dynamics and environmental change in these regions is crucial for ensuring efficient policy planning and progress toward social and ecological sustainability. Here, we provide an overview of population trends and dynamics in the Ganges–Brahmaputra, Mekong and Amazon deltas. Using multiple data sources, including census data and Demographic and Health Surveys, a discussion regarding the components of population change is undertaken in the context of environmental factors affecting the demographic landscape of the three delta regions. We find that the demographic trends in all cases are broadly reflective of national trends, although important differences exist within and across the study areas. Moreover, all three delta regions have been experiencing shifts in population structures resulting in aging populations, the latter being most rapid in the Mekong delta. The environmental impacts on the different components of population change are important, and more extensive research is required to effectively quantify the underlying relationships. The paper concludes by discussing selected policy implications in the context of sustainable development of delta regions and beyond.     

Obstacles to climate change adaptation decisions: a case study of sea-level rise and coastal protection measures in Kiribati

International aid is increasingly focused on adaptation to climate change. At recent meetings of the parties to the United Nations Framework Convention on Climate Change, the developed world agreed to rapidly increase international assistance to help the developing world respond to the impacts of climate change. In this paper, we examine the decision-making challenges facing internationally supported climate change adaptation projects, using the example of efforts to implement coastal protection measures (e.g. sea walls, mangrove planting) in Kiribati. The central equatorial Pacific country is home to the Kiribati Adaptation Project, the first national-level climate change adaptation project supported by the World Bank. Drawing on interview and document research conducted over an 8-year period, we trace the forces influencing decisions about coastal protection measures, starting from the variability and uncertainty in climate change projections, through the trade-offs between different measures, to the social, political, and economic context in which decisions are finally made. We then discuss how sub-optimal adaptation measures may be implemented despite years of planning, consultation, and technical studies. This qualitative analysis of the real-world process of climate change adaptation reveals that embracing a culturally appropriate and short-term (~20 years) planning horizon, while not ignoring the longer-term future, may reduce the influence of scientific uncertainty on decisions and provide opportunities to learn from mistakes, reassess the science, and adjust suboptimal investments. The limiting element in this approach to adaptation is likely to be the availability of consistent, long-term financing.     

Integration, synthesis and climate change adaptation: a narrative based on coastal wetlands at the regional scale

The idea that integration and synthesis are critical for designing climate change adaptation and mitigation is well entrenched conceptually. Here, we review the concepts of adaptation, synthesis and integration and apply them to the case study of coastal wetlands in South East Queensland, Australia. The distribution and condition of coastal wetlands will change as climate changes. This will create conservation challenges and economic costs, but these can be minimised by drawing from a broad sectoral perspective in undertaking adaptation planning and by ensuring integration into policy. Our review indicates that adaptations to sea level rise that are focussed on wetland and biodiversity conservation are likely to have impacts for urbanisation patterns. Planning regulations that provide spatial buffering around wetlands may give rise to more compact urban forms that may lead to reductions in the cost of defence against sea level rise, reduce energy usage per person and provide more green space. However, more compact urban forms could exacerbate heat island effects and place greater burden on the economically disadvantaged as, for example, single-family homes become more expensive. Planning for climate change needs to balance these equity and cross-sectoral issues in order to reduce the likelihood of unforeseen negative consequences.     

Vulnerability of Catalan (NW Mediterranean) ports to wave overtopping due to different scenarios of sea level rise

The overtopping of port breakwaters may affect the assets located at the breakwater lee side. If adaptation measures are not taken, the sea level rise will increase the overtopping discharges putting those assets at significant risk. This study compares, at a regional scale, overtopping discharges over port breakwaters for three storm conditions (return periods of 1, 5 and 50 years) under present climate as well as for three scenarios of sea level rise based on recent projections. The results indicate that, for the worst storm and sea level rise conditions, the overtopping discharge would not be negligible (larger than 1 l/s/m) in 35 ports (84 %), in contrast to only 18 ports (42 %) being affected under present conditions. In addition, in 28 ports (65 %) the overtopping would be at least one order of magnitude larger than for present conditions. In the case of large storms, in 2 ports the overtopping discharge exceeds 200 l/s/m (the discharge that can initiate breakwater damage) under present conditions, while in the worst scenario of sea level rise the number of ports exceeding this value would be 7. On the other hand, the vulnerability of each port for which overtopping flow is greater than an acceptable discharge flux is assessed, and regional maps of vulnerability are plotted. For the worst storm conditions, 23 % of the Catalan ports have risks associated with overtopping under present climate conditions. This percentage would increase to 47 % in the worst sea level rise scenario.     

Economic,equitable, and affordable adaptations to protect coastal settlements against storm surge inundation

The distribution of risk of coastal inundation, and the potential benefits of adapting to protect against inundation, vary greatly both within and between coastal communities. This diversity is a result of physical factors, such as the risk of storm surge, sea level rise projections, and the topography of the landscape, as well as socio-economic factors, such as the level of development, and the capacity within the community to adapt. Despite this strong local variation, various communities share common characteristics that constrain or enable different adaptation options in different situations. Understanding these drivers is likely to be important in engaging coastal communities in the discussion around adaptation and may provide new insights into which adaptation options are suitable for each of our at-risk coastal communities. We performed a property-level analysis of 6 suburb-sized case studies distributed along the coast of Queensland, Australia. We assessed the potential economic costs of inundation events now and in the future under sea level rise projections, and the potential avoided costs following adaptation to protect against inundation. We went beyond this to estimate the distribution of risk in each community and compared the potential costs of adaptation with the capacity of the community to pay for their implementation. We used these insights to propose a typology of coastal communities based on their exposure to total inundation risk, the distribution of that risk within the community, and their capacity to adapt.     

2014, The “year without a summer” in Italy: news media coverage and implications for the climate change debate

In 2014, there was virtually no summer in northern and central-southern Italy. Storm after storm battered the peninsula, triggering floods and landslides from Veneto to Puglia. We studied the coverage of “the year without a summer” in Italy by analyzing the content of 171 news articles from two influential online newspapers. Our software-based analysis enabled us to observe that the two newspapers hardly ever mentioned climate change in their coverage of the weather anomaly that affected Italy in the summer of 2014. This type of coverage is in line with climate science, according to which there is no evidence of a climate change-related influence on summer precipitation patterns in Southern Europe—whereas such influence has been documented for northern Europe. We compared our results with a recent paper, which documented that the same online dailies chose to represent the particularly hot summer of 2012 in Italy as a direct consequence of climate change. We corroborated this comparison also on the basis of a preliminary analysis we performed on the media coverage of the exceptionally hot and arid summer of 2015 in Italy.     

Flood risk,climate change and settlement development: a micro-scale assessment of Austrian municipalities

This paper analyses the influence of climate change and land development on future flood risk for selected Austrian flood-prone municipalities. As part of an anticipatory micro-scale risk assessment we simulated four different inundation scenarios for current and future 100- and 300-year floods (which included a climate change allowance), developed scenarios of future settlement growth in floodplains and evaluated changes in flood damage potentials and flood risk until the year 2030. Findings show that both climate change and settlement development significantly increase future levels of flood risk. However, the respective impacts vary strongly across the different cases. The analysis indicates that local conditions, such as the topography of the floodplain, the spatial allocation of vulnerable land uses or the type of land development (e.g. residential, commercial or industrial) in the floodplain are the key determinants of the respective effects of climate change and land development on future levels of flood risk. The case study analysis highlights the general need for a more comprehensive consideration of the local determinants of flood risk in order to increase the effectiveness of an adaptive management of flood risk dynamics.