Climate Awareness and Adaptation Efficacy for Livelihood Security against Sea Level Rise in Coastal Bangladesh

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

10.5194/egusphere-egu21-1404 ◽

2021 ◽

Author(s):

Attila N. Lazar ◽

Robert J. Nicholls ◽

Craig W. Hutton ◽

Andres Payo ◽

Helen Adams ◽

...

Keyword(s):

Sea Level Rise ◽

Sea Level ◽

Integrated Assessment ◽

Integrated Assessment Model ◽

Assessment Model ◽

Catchment Management ◽

Economic Changes ◽

Coastal Bangladesh ◽

Social Ecological ◽

The Impact

<p>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.</p>

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Glacial Contributions to 21st Century Sea Level Rise

Eos ◽

10.1029/2020eo143700 ◽

2020 ◽

Vol 101 ◽

Author(s):

Kate Wheeling

Keyword(s):

Sea Level Rise ◽

Sea Level ◽

21St Century ◽

Mass Change ◽

Sources Of Uncertainty

Researchers identify the main sources of uncertainty in projections of global glacier mass change, which is expected to add about 8–16 centimeters to sea level, through this century.

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