• Energy Research

In the Indian Sundarban, multiple attributes and interactions of natural hazards, exposure, and vulnerability pose severe threats to lives and livelihoods. Understanding the cause-and-effect relationships contributing to the risk of loss of sustainable livelihoods has become imperative but has not yet been holistically explored in a single study that provides a broader picture of all possible complex interactions. This study used the impact chain tool to holistically understand the risk that manifests as a result of interactions of hazards, exposure, and vulnerability. The secondary literature and authors’ observations helped us structure the first draft of the impact chain, which was further developed and validated through fourteen gender-disaggregated interviews with key informants and delta dwellers. This validation process identified the complex interconnections contributing to risk as experienced by experts and delta dwellers, which is seldom reflected through exclusively quantitative data. A quantitative analysis of the qualitative data strongly indicated that tropical cyclones, rainfall variability, and storms are the dominant hazards that affect social–ecological vulnerability manifested through mangrove degradation, land loss due to erosion, and embankment breaching. Social vulnerability is caused by processes and factors that are either directly or indirectly influenced by natural hazards and social–ecological factors. Processes such as increasing seasonal male migration, uncertain agricultural income, and a lack of hazard-resistant housing exacerbates social vulnerability. Embankment breaching, the salinization of land and water, land loss due to erosion, mangrove degradation, land conversion, and groundwater abstraction were identified as the fundamental threats that can lead to a loss of sustainable livelihoods of the people if left unaddressed.

In the Indian Sundarban, multiple attributes and interactions of natural hazards, exposure, and vulnerability pose severe threats to lives and livelihoods. Understanding the cause-and-effect relationships contributing to the risk of loss of sustainable livelihoods has become imperative but has not yet been holistically explored in a single study that provides a broader picture of all possible complex interactions. This study used the impact chain tool to holistically understand the risk that manifests as a result of interactions of hazards, exposure, and vulnerability. The secondary literature and authors’ observations helped us structure the first draft of the impact chain, which was further developed and validated through fourteen gender-disaggregated interviews with key informants and delta dwellers. This validation process identified the complex interconnections contributing to risk as experienced by experts and delta dwellers, which is seldom reflected through exclusively quantitative data. A quantitative analysis of the qualitative data strongly indicated that tropical cyclones, rainfall variability, and storms are the dominant hazards that affect social–ecological vulnerability manifested through mangrove degradation, land loss due to erosion, and embankment breaching. Social vulnerability is caused by processes and factors that are either directly or indirectly influenced by natural hazards and social–ecological factors. Processes such as increasing seasonal male migration, uncertain agricultural income, and a lack of hazard-resistant housing exacerbates social vulnerability. Embankment breaching, the salinization of land and water, land loss due to erosion, mangrove degradation, land conversion, and groundwater abstraction were identified as the fundamental threats that can lead to a loss of sustainable livelihoods of the people if left unaddressed.

The use of nature-based solutions (NbS) to address the risks posed by hydro-meteorological hazards have not yet become part of the mainstream policy response, and one of the main reasons cited for this, is the lack of evidence that they can effectively reduce disaster risk. This paper addresses this issue, by providing model-based evidence from five European case studies which demonstrate the effectiveness of five different NbS in reducing the magnitude of the hazard and thus risk, in present-day and possible future climates. In OAL-Austria, the hazard is a deep-seated landslide, and the NbS analysed is afforestation. Modelling results show that in today's climate and a landcover scenario of mature forest, a reduction in landslide velocity of 27.6 % could be achieved. In OAL-Germany, the hazard is river flooding and the NbS analysed is managed grazing with removal of woody vegetation. Modelling results show that the NbS could potentially reduce maximum flood water depth in the near-future (2031–2060) and far-future (2070–2099), by 0.036 m and 0.155 m, respectively. In OAL-Greece, the hazard is river flooding, and the NbS is upscaled natural storage reservoirs. Modelling results show that in a possible future climate the upscaled NbS show most potential in reducing the total flooded area by up to 1.26 km2. In OAL-Ireland, the hazard is surface and river flooding, and the NbS is green roofs. Results from a modelled upscaling analysis under two different climate scenarios show that both maximum flood water depth, and total flooded area were able to be reduced. In OAL-UK, the hazard is shallow landslides, and the NbS is high-density planting of two different tree species. Modelling results under two different climate scenarios show that both tree species were able to improve slope stability, and that this increased over time as the NbS matured. The significance of these results is discussed within the context of the performance of the NbS over time, to different magnitude events, impact with stakeholders in engendering wider support for the adoption of the NbS in the OALs, and the uncertainty in the modelling analyses.

The use of nature-based solutions (NbS) to address the risks posed by hydro-meteorological hazards have not yet become part of the mainstream policy response, and one of the main reasons cited for this, is the lack of evidence that they can effectively reduce disaster risk. This paper addresses this issue, by providing model-based evidence from five European case studies which demonstrate the effectiveness of five different NbS in reducing the magnitude of the hazard and thus risk, in present-day and possible future climates. In OAL-Austria, the hazard is a deep-seated landslide, and the NbS analysed is afforestation. Modelling results show that in today's climate and a landcover scenario of mature forest, a reduction in landslide velocity of 27.6 % could be achieved. In OAL-Germany, the hazard is river flooding and the NbS analysed is managed grazing with removal of woody vegetation. Modelling results show that the NbS could potentially reduce maximum flood water depth in the near-future (2031–2060) and far-future (2070–2099), by 0.036 m and 0.155 m, respectively. In OAL-Greece, the hazard is river flooding, and the NbS is upscaled natural storage reservoirs. Modelling results show that in a possible future climate the upscaled NbS show most potential in reducing the total flooded area by up to 1.26 km2. In OAL-Ireland, the hazard is surface and river flooding, and the NbS is green roofs. Results from a modelled upscaling analysis under two different climate scenarios show that both maximum flood water depth, and total flooded area were able to be reduced. In OAL-UK, the hazard is shallow landslides, and the NbS is high-density planting of two different tree species. Modelling results under two different climate scenarios show that both tree species were able to improve slope stability, and that this increased over time as the NbS matured. The significance of these results is discussed within the context of the performance of the NbS over time, to different magnitude events, impact with stakeholders in engendering wider support for the adoption of the NbS in the OALs, and the uncertainty in the modelling analyses.

AbstractRiver deltas globally are highly exposed and vulnerable to natural hazards and are often over-exploited landforms. The Global Delta Risk Index (GDRI) was developed to assess multi-hazard risk in river deltas and support decision-making in risk reduction interventions in delta regions. Disasters have significant impacts on the progress towards the Sustainable Development Goals (SDGs). However, despite the strong interlinkage between disaster risk reduction and sustainable development, global frameworks are still developed in isolation and actions to address them are delegated to different institutions. Greater alignment between frameworks would both simplify monitoring progress towards disaster risk reduction and sustainable development and increase capacity to address data gaps in relation to indicator-based assessments for both processes. This research aims at aligning the GDRI indicators with the SDGs and the Sendai Framework for Disaster and Risk Reduction (SFDRR). While the GDRI has a modular indicator library, the most relevant indicators for this research were selected through a delta-specific impact chain designed in consultation with experts, communities and stakeholders in three delta regions: the Red River and Mekong deltas in Vietnam and the Ganges–Brahmaputra–Meghna (GBM) delta in Bangladesh and India. We analyse how effectively the 143 indicators for the GDRI match (or not) the SDG and SFDRR global frameworks. We demonstrate the interconnections of the different drivers of risk to better inform risk management and in turn support delta-level interventions towards improved sustainability and resilience of these Asian mega-deltas.

AbstractRiver deltas globally are highly exposed and vulnerable to natural hazards and are often over-exploited landforms. The Global Delta Risk Index (GDRI) was developed to assess multi-hazard risk in river deltas and support decision-making in risk reduction interventions in delta regions. Disasters have significant impacts on the progress towards the Sustainable Development Goals (SDGs). However, despite the strong interlinkage between disaster risk reduction and sustainable development, global frameworks are still developed in isolation and actions to address them are delegated to different institutions. Greater alignment between frameworks would both simplify monitoring progress towards disaster risk reduction and sustainable development and increase capacity to address data gaps in relation to indicator-based assessments for both processes. This research aims at aligning the GDRI indicators with the SDGs and the Sendai Framework for Disaster and Risk Reduction (SFDRR). While the GDRI has a modular indicator library, the most relevant indicators for this research were selected through a delta-specific impact chain designed in consultation with experts, communities and stakeholders in three delta regions: the Red River and Mekong deltas in Vietnam and the Ganges–Brahmaputra–Meghna (GBM) delta in Bangladesh and India. We analyse how effectively the 143 indicators for the GDRI match (or not) the SDG and SFDRR global frameworks. We demonstrate the interconnections of the different drivers of risk to better inform risk management and in turn support delta-level interventions towards improved sustainability and resilience of these Asian mega-deltas.

Disasters have significant impacts on the progress towards achieving the Sustainable Development Goals (SDGs). However, the interlinkage between sustainable development and disaster risk reduction is not considered enough in risk assessment tools. A greater alignment with global frameworks would ease the monitoring while increasing the capacity to address data availability issues for indicator-based assessments.To bridge this gap, we use the Global Delta Risk Index (GDRI), which is composed of multiple components to assess risks to livelihoods: hazards, vulnerability, and exposure of social-ecological systems. The modular library of indicators of the GDRI has been further aligned with the Sustainable Development Goals (SDG) and the Sendai Framework for Disaster and Risk Reduction (SFDRR). To improve the accuracy of the risk assessment, the list of indicators has been weighted and scored through consultation with stakeholders.This research presents the initial results of a multi-hazard risk assessment that encompasses SDG and SFDRR indicators in three Asian river deltas: Ganges-Brahmaputra-Meghna, Mekong and Red River. This work aims at better informing risk management and supporting delta-level interventions to influence progress towards sustainability and resilience of river deltas.