Potential social-ecological development of coastal Bangladesh through the 21st century

Deltas occupy only 1% of global land surface area, but contain 7% of the global human population (ca. 500 million). The influence of changing and interacting climates, demography, economy, land use and coastal/catchment management on deltaic social-ecological systems is complex and little understood. We apply a new and innovative integrated assessment model: The Delta Dynamic Integrated Emulator Model (&#916;DIEM) to coastal Bangladesh to explore a range of plausible future scenarios and quantify the sensitivities of selected environmental and socio-economic outcomes to key external and internal drivers. &#916;DIEM is a tightly coupled integrated assessment platform considering climate and environmental change, demographic changes, economic changes, household decision making and governance, and designed to support the delta planning in Bangladesh. &#916;DIEM allows the testing of a large number of water-based structural and policy interventions within a robust scenario framework, as well as quantify different development trajectories and their trade-offs. In this sensitivity analysis, we quantified the impact of (i) climate (precipitation, temperature and runoff), (ii) relative sea-level rise, (iii) cyclone frequency, (iv) embankment maintenance, (v) population size, (vi) economic changes at household level such as selling price of crops, cost of food, etc., (vii) land cover, and (viii) farming practices on trajectories of inundated area, soil salinity, rice productivity, poverty, income inequality and GDP/capita, assuming two contrasting scenarios in a more Positive and a more Negative World. Trajectories of these plausible futures showed a clear separation and the long-term trends are greatly influenced by the combinations of scenario assumptions. Our systemic results indicate a diverse potential set of futures for coastal Bangladesh, where good governance and adaptation could effectively mitigate the threat of sea-level rise-induced catastrophic inundation and other adverse impacts of the changing climate. However, societal inequality requires special attention otherwise climate-sensitive population groups may be left behind.

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Application of an Integrated Assessment Model (IAM) to for strategic scale delta assessment of socio-ecological risk: Supporting Policy in Coastal Bangladesh

10.5194/egusphere-egu2020-12548 ◽

2020 ◽

Author(s):

Craig Hutton ◽

Robert Nicholls ◽

Alex Chapman ◽

Charlotte Marcinko ◽

Munsur Rahman ◽

...

Keyword(s):

Integrated Assessment ◽

Policy Decision ◽

Integrated Assessment Model ◽

Assessment Model ◽

The Sustainable Development ◽

Coastal Bangladesh ◽

Strategic Risk ◽

South Central ◽

Trade Offs ◽

The Government

There is growing recognition that new approaches, underpinned by more system-oriented decision support tools, will be required to facilitate development compatible with the Sustainable Development Goals (SDGs) and to prevent the risk of dangerous socio-environmental breakdown. We demonstrate the potential of Integrated Assessment Models (IAMs) to inform strategic policy decision making at a regional level, helping to understand key trade-offs as well as indirect or unintended impacts. The stakeholder co-produced Delta Dynamic Emulator Model (&#916;DIEM) model is applied to the southwest coastal zone (pop. 14m) where high rates of extreme poverty prevail. The model integrates biophysical drivers, ecosystem services and community level household wellbeing, and in this work is applied an behalf of the Planning Commission of the Government of Bangladesh in order to assess strategic risk in coastal Bangladesh (2050) and particularly to support the Bangladesh Delta Plan 2100. The intervention we investigated included i) A proposed extensive polder network in the south-central region of coastal Bangladesh ii) Strategic development of a chronically waterlogged area of the delta. In both areas we highlight insights on implications of biophysical drivers on poverty, livelihoods and inequality as well as on risk transfer between regions and populations associated with implementation. In doing so we critically assess IAMs&#8217; growing potential to ask and explore key questions and scenarios about the functioning of integrated biophysical and socioeconomic systems. Finally, we point to ongoing applications of the model in West Bengal

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Contrasting development trajectories for coastal Bangladesh to the end of century

Regional Environmental Change ◽

10.1007/s10113-020-01681-y ◽

2020 ◽

Vol 20 (3) ◽

Cited By ~ 1

Author(s):

Attila Nándor Lázár ◽

Robert James Nicholls ◽

Jim William Hall ◽

Emily Jane Barbour ◽

Anisul Haque

Keyword(s):

Coastal Zone ◽

Integrated Assessment ◽

Economic Cost ◽

Integrated Assessment Model ◽

Assessment Tools ◽

Assessment Model ◽

Equity Issues ◽

Coastal Bangladesh ◽

Development Trajectory ◽

Development Trajectories

Abstract Bangladesh is one of the most climate-sensitive countries globally, creating significant challenges for future development. Here we apply an integrated assessment model — Delta Dynamic Integrated Emulator Model (ΔDIEM) — to the south-west coastal zone of Bangladesh to explore the outcomes of four contrasting and plausible development trajectories under different climate and socio-economic scenarios: (1) embankment rehabilitation; (2) build elevation via controlled sedimentation; (3) planned migration (managed retreat) and (4) ‘do nothing’ (unplanned migration and abandonment). Embankment rehabilitation reduces flood risk, but at a high economic cost and enhancing waterlogging. Planned and unplanned migration combined with limited infrastructure management and governance both result in significant abandonment. Building elevation through sedimentation has the potential for increased environmental and economic sustainability but raises equity issues. Poverty and inequality persist across all scenarios, and outmigration from the coastal zone continues, although the magnitude is sensitive to assumptions about sea-level rise, socio-economic development and development trajectory. Integrated assessment tools linking the environment, people and policy choices, such as the ΔDIEM used here, highlight the complex interactions occurring in a dynamic delta environment. Such analysis supports informed management, development and adaptation.

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Climate assessment of emissions scenarios for use in WG3 of the IPCC’s Sixth Assessment Report

10.5194/egusphere-egu2020-18182 ◽

2020 ◽

Author(s):

Matthew Gidden ◽

Zebedee Nicholls ◽

Edward Byers ◽

Gaurav Ganti ◽

Jarmo Kikstra ◽

...

Keyword(s):

Atmospheric Chemistry ◽

Integrated Assessment ◽

Integrated Assessment Model ◽

Assessment Model ◽

Model Description ◽

Carbon Budgets ◽

Climate Assessment ◽

Emissions Scenarios ◽

Paris Climate Agreement ◽

The Impact

Consistent and comparable climate assessments of scenarios are critical within the context of IPCC assessment reports. Given the number of scenarios assessed by WG3, the assessment &#8220;pipeline&#8221; must be almost completely automated. Here, we present the application of a new assessment pipeline which combines state-of-the-art components into a single workflow in order to derive climate outcomes for integrated assessment model (IAM) scenarios assessed by WG3 of the IPCC. A consistent analysis ensures that WG3&#8217;s conclusions about the socioeconomic transformations required to maintain a safe climate are based on the best understanding of our planetary boundaries from WG1. For example, if WG1 determines that climate sensitivity is higher than previously considered, then WG3 could incorporate this insight by e.g. considering much smaller remaining carbon budgets for any given temperature target.&#160;The scenario-climate assessment pipeline is comprised of three primary components. First, a consistent harmonization algorithm which maintains critical model characteristics between harmonized and unharmonized scenarios [1] is employed to harmonize emissions trajectories to a common and consistent historical dataset as used in CMIP6 [2]. Next, a scenario&#8217;s reported emissions trajectories are analyzed as to the completeness of its species and sectoral coverage. A consistent set of 14 emissions species are expected, aligning with published work within ScenarioMIP and CMIP6 (see ref [2], Table 2). Should any component of this full set of emissions trajectories be absent for a given scenario, an algorithm (e.g., generalised quantile walk [3]) is employed in order to &#8220;back-fill&#8221; missing species at the native model regional resolution. Finally, full emissions scenarios are analyzed by an Earth System Model emulator, e.g., MAGICC [4].&#160;In this presentation, we explore differences in climate assessments and estimated remaining carbon budgets across various components of the pipeline for available scenarios in the literature. We consider the impact of alternative choices, especially those made in prior assessments by the IPCC (AR5, SR15), including, for example, the historical emissions database used, the effect of harmonization and back-filling, as well as the version and setup of MAGICC used.&#160;&#160;References&#160;[1] Gidden, M.J., Fujimori, S., van den Berg, M., Klein, D., Smith, S.J., van Vuuren, D.P. and Riahi, K., 2018. A methodology and implementation of automated emissions harmonization for use in Integrated Assessment Models. Environmental Modelling & Software, 105, pp.187-200.&#160;[2] Gidden, M. J., Riahi, K., Smith, S. J., Fujimori, S., Luderer, G., Kriegler, E., van Vuuren, D. P., van den Berg, M., Feng, L., Klein, D., Calvin, K., Doelman, J. C., Frank, S., Fricko, O., Harmsen, M., Hasegawa, T., Havlik, P., Hilaire, J., Hoesly, R., Horing, J., Popp, A., Stehfest, E., and Takahashi, K.: Global emissions pathways under different socioeconomic scenarios for use in CMIP6: a dataset of harmonized emissions trajectories through the end of the century, Geosci. Model Dev., 12, 1443-1475, https://doi.org/10.5194/gmd-12-1443-2019, 2019.&#160;[3] Teske, S. et al., Achieving the Paris Climate Agreement Goals. Springer, 2019.&#160;[4] Meinshausen, M., Raper, S.C. and Wigley, T.M., 2011. Emulating coupled atmosphere-ocean and carbon cycle models with a simpler model, MAGICC6&#8211;Part 1: Model description and calibration. Atmospheric Chemistry and Physics, 11(4), pp.1417-1456.

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Devising Mineral Resource Supply Pathways to a Low-Carbon Electricity Generation by 2100

Resources ◽

10.3390/resources8010033 ◽

2019 ◽

Vol 8 (1) ◽

pp. 33 ◽

Cited By ~ 6

Author(s):

Antoine Boubault ◽

Nadia Maïzi

Keyword(s):

Life Cycle ◽

Integrated Assessment ◽

Fossil Fuels ◽

Mineral Resources ◽

Integrated Assessment Model ◽

Assessment Model ◽

Raw Material ◽

Low Carbon ◽

Life Cycle Inventories ◽

The Impact

Achieving a “carbon neutral” world by 2100 or earlier in a context of economic growth implies a drastic and profound transformation of the way energy is supplied and consumed in our societies. In this paper, we use life-cycle inventories of electricity-generating technologies and an integrated assessment model (TIMES Integrated Assessment Model) to project the global raw material requirements in two scenarios: a second shared socioeconomic pathway baseline, and a 2 °C scenario by 2100. Material usage reported in the life-cycle inventories is distributed into three phases, namely construction, operation, and decommissioning. Material supply dynamics and the impact of the 2 °C warming limit are quantified for three raw fossil fuels and forty-eight metallic and nonmetallic mineral resources. Depending on the time horizon, graphite, sand, sulfur, borates, aluminum, chromium, nickel, silver, gold, rare earth elements or their substitutes could face a sharp increase in usage as a result of a massive installation of low-carbon technologies. Ignoring nonfuel resource availability and value in deep decarbonation, circular economy, or decoupling scenarios can potentially generate misleading, contradictory, or unachievable climate policies.

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Ensemble Projection of the Sea Level Rise Impact on Storm Surge and Inundation in the Coastal Bangladesh

10.5194/nhess-2017-216 ◽

2017 ◽

Cited By ~ 1

Author(s):

Mansur Ali Jisan ◽

Shaowu Bao ◽

Leonard J. Pietrafesa

Keyword(s):

Sea Level Rise ◽

Sea Level ◽

Storm Surge ◽

21St Century ◽

Coastal Region ◽

Climate Scenario ◽

Future Change ◽

Coastal Bangladesh ◽

Projected Changes ◽

The Impact

Abstract. The hydrodynamic model Delft3D is used to study the impact of Sea Level Rise (SLR) on storm surge and inundation in the coastal region of Bangladesh. To study the present day inundation scenario, track of two known tropical cyclones (TC) were used: Aila (Category 1; 2009) and Sidr (Category 5; 2007). Model results were validated with the available observations. Future inundation scenarios were generated by using the strength of TC Sidr, TC Aila and an ensemble of historical TC tracks but incorporating the effect of SLR. Since future change in storm surge inundation under SLR impact is a probabilistic incident, that’s why a probable range of future change in inundated area was calculated by taking in to consideration the uncertainties associated with TC tracks, intensities and landfall timing. The model outputs showed that, the inundated area for TC Sidr, which was calculated as 1860 km2, would become 31 % higher than the present day scenario if a SLR of 0.26 meter occurs during the mid-21st century climate scenario. Similar to that, an increasing trend was found for the end of the 21st century climate scenario. It was found that with a SLR of 0.54 meter, the inundated area would become 53 % higher than the present day case. Along with the inundation area, the impact of SLR was examined for the changes in future storm surge level. A significant increase of 21 % was found in storm surge level for the case of TC Sidr in Barisal station if a Sea Level Rise of 0.26 meter occurs at the middle of the 21st century. Similar to that, an increase of 37 % was found in storm surge level with a SLR of 0.54 meter in this location for the end of the 21st century climate scenario. Ensemble projections based on uncertainties of future TC events also showed that, for a change of 0.54 meters in SLR, the inundated area would range between 3500–3750 km2 whereas for present day SLR simulations it was found within the range of 1000–1250 km2. These results revealed that even if the future TCs remain at the same strength as at present, the projected changes in SLR will generate more severe threats in terms of surge height and extent of inundated area.

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An Assessment of the Radiological Impact of Coastal Erosion of the UK Low-Level Waste Repository

ASME 2011 14th International Conference on Environmental Remediation and Radioactive Waste Management, Parts A and B ◽

10.1115/icem2011-59137 ◽

2011 ◽

Author(s):

Trevor Sumerling ◽

Paul Fish ◽

George Towler ◽

James Penfold ◽

John Shevelan ◽

...

Keyword(s):

Sea Level Rise ◽

Sea Level ◽

Coastal Erosion ◽

Assessment Model ◽

Coastal System ◽

Future Evolution ◽

Low Level ◽

Waste Repository ◽

The Uk ◽

The Impact

The UK Low Level Waste Repository Ltd submitted an Environmental Safety Case for the disposal of low-level waste to our regulator, the Environment Agency, on the 1st of May 2011. This includes assessments of the long-term radiological safety of past and future disposals. A particular feature of the Low Level Waste Repository (LLWR) is that, because of its proximity to the coast, the site is vulnerable to coastal erosion. Our present understanding is that the site will be eroded on a timescale of a few hundred to a few thousand years, with consequent disruption of the repository, and dispersal of the wastes. We have undertaken a programme of scientific research and monitoring to characterise the evolution and function of the current coastal system that provides a basis for forecasting its future evolution. This has included modelling of contemporary hydrodynamics, geomorphological mapping, repeat LiDAR and aerial photographic surveys to detect patterns and rates of change, coastal inspections and reconstructions of post-glacial (i.e. last 15,000 years) sea levels and sediment budgets. Estimates of future sea-level rise have been derived from international sources and consideration given to the impact of such on the local coastline. Two alternative models of coastal recession have then been applied, one empirical and one physical-process based, taking account of the composition of Quaternary-age sediments between the coast and the site and uncertainties in future local sea level change. Comparison of the ranges of calculated times to site contact with sea-level rise indicate that the repository is most likely to be disrupted by undercutting of the engineered vaults and of the trenches. A novel and flexible radiological assessment model has been developed to analyse the impacts of the erosion of the repository and subsequent dispersal of wastes. The model represents the spatial layout of the site and distribution of radionuclides within the repository and is able to take account of a range of uncertainties. These include uncertainties related to the rate of erosion through the facility, amounts of co-erosion of geological and cap materials, alternative assumptions for residence of waste materials on the beach, alternative waste form associations, the wider dispersion of the eroded materials and marine sorption/desorption processes. Results indicate assessed annual doses and risks that are consistent with regulatory guidance levels.

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