Bangladesh and the Surging Sea

The report evaluates the risk of permanent inundation and frequent flooding in Bangladesh by 2100. Using high-resolution elevation data and two emission scenarios (RCP 2.6 and RCP 8.5), it finds that under high emissions, over 1,000 km2 of land and 8.6 lakh people could be permanently submerged. The Chittagong division is identified as having the highest population exposure risk. The analysis notes that results may be lower bounds due to elevation model errors and does not account for future shoreline defenses or population changes.

• Under the RCP 8.5 scenario (unabated carbon emissions), more than 1,000 km2 of land in Bangladesh could be permanently submerged by 2100, affecting over 8.6 lakh people, which represents approximately 0.7% of the total land area and 0.6% of the population.
• Population and land exposure to frequent flooding (below the mean annual maximum water level) are more than double the figures for permanent inundation. Under RCP 8.5, the population exposed to frequent flooding by 2100 is projected at 20.7 lakh people.
• The Chittagong division is the most vulnerable in terms of population exposure, with over twice as many people at risk of permanent submergence as in Barisal or Khulna under high emissions. In 2100, an estimated 9.4 lakh people in Chittagong are exposed during the average maximum annual flood.
• Local relative sea level rise is significantly amplified by land subsidence, particularly west of the Ganges Delta, where relative rise could reach 2.37m by 2100 under RCP 8.5, which is triple the global sea level rise alone.
• Reducing global emissions (RCP 2.6) would decrease the number of people and land area exposed to routine storm surge and tides by approximately 18%. Across districts with a median exposure of 1,000 people or more, RCP 2.6 reduces both permanent and routine inundation by an average of 19%.
• The report warns that the findings may be lower bounds of actual potential exposure because the SRTM elevation model provides surface elevations rather than bare earth elevations, potentially overestimating height in areas with vegetation or tall buildings.

APA

Climate and Development Knowledge Network (n.d.). Bangladesh and the Surging Sea. https://cdkn.org/sites/default/files/files/CDKNJ5476-Bangladesh-and-Surging-Sea-RRA-report-A4-170606-WEB1.pdf

Chicago

Climate and Development Knowledge Network. Bangladesh and the Surging Sea. n.d. https://cdkn.org/sites/default/files/files/CDKNJ5476-Bangladesh-and-Surging-Sea-RRA-report-A4-170606-WEB1.pdf.

Wikipedia

{{cite report |author=Climate and Development Knowledge Network |title=Bangladesh and the Surging Sea |url=https://cdkn.org/sites/default/files/files/CDKNJ5476-Bangladesh-and-Surging-Sea-RRA-report-A4-170606-WEB1.pdf |access-date=17 August 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{climateanddevelopmentknowledgenetworkndbangladesh, author = {{Climate and Development Knowledge Network}}, title = {{Bangladesh and the Surging Sea}}, institution = {Climate and Development Knowledge Network}, url = {https://cdkn.org/sites/default/files/files/CDKNJ5476-Bangladesh-and-Surging-Sea-RRA-report-A4-170606-WEB1.pdf}, urldate = {2026-08-17}, note = {Indexed by Climate Insights Directory} }