Methodology
24/7 Wall St. used data from Climate Central — an independent organization of scientists and journalists researching and reporting on climate change — to identify major metropolitan areas and urban agglomerations that are projected to be at risk of substantial flooding by 2050 as a result of sea level rise due to climate change.
To look for cities at risk, we first identified the countries with the largest populations in areas that will lie below projected high tide lines by 2050, using the more pessimistic rcp 8.5 projection of ongoing global carbon dioxide emissions and employing an assessment of anticipated sea level rise by Kopp et al., published in 2017. Based on this same model, we used Climate Central’s Coastal Risk Screening tool to review the urban agglomerations and metropolitan areas that fall within high-risk countries that have populations of at least 5 million residents and are at risk of substantial inundation by 2050.
Carbon emissions figures are for 2017 and are from the Global Carbon Project 2018, accessed through the Integrated Carbon Observation System of the Department of Physical Geography and Ecosystem Science at Lund University. These figures are expressed in millions of metric tons of CO2 emitted from fossil fuels and cement production within a country’s borders.
City population estimates are projections for 2020, and are from the 2018 Revision of World Urbanization Prospects, which was produced by the Population Dynamics Division of the United Nations’ Department of Economic and Social Affairs.