The steady rise in global surface temperatures, monitored since the 1880s, is largely attributed to human-caused greenhouse gas emissions. With rising temperatures, the world’s ice has been melting and the sea level rising. As a result, barring major interventions, sooner or later thousands of coastal communities around the world will become uninhabitable.
The most recent assessment published this June in the science journal Nature found that Antarctica is melting at triple the rate it did in 2007 and previous projections may have underestimated the continent’s slow disappearance.
According to a 2017 study, if rising carbon emissions and ice sheet loss continue at their current rate, global sea levels could rise by an estimated 8 feet by the year 2100. And if, in the even more distant future, all of the Antarctic ice sheet — which comprises the vast majority of Earth’s freshwater supply — melts, sea levels would rise by approximately 200 feet.
Change on such a large scale is incremental and can seem quite distant. Still, any large scale solution to the problem would need to be implemented relatively soon. Already, for many areas, flooding is inevitable and the problem is imminent. According to NOAA scientists, high tide flooding across U.S. coastlines this year may surpass what was typical flooding 20 years ago by as much as 60%.
24/7 Wall St. reviewed data modeled by environmental watchdog group the Union of Concerned Scientists, which identified U.S. coastal communities expected to face chronic and disruptive flooding before the end of the century — defined as having 10% or more of livable land area flooded at least 26 times per year.
Across U.S. coastal cities within the next 30 years, more than 300,000 homes worth a combined $117.5 billion are likely to be at risk of chronic tidal flooding, according to UCS analysis and projections.
We reviewed the coastal communities in which at least 10% of livable area is expected to experience chronic flooding by 2060. Places are ranked by the number of residents that live in parts of the community expected to be under water by 2060.
Cities and institutions can mitigate flood damage by implementing wetlands, levees, and other mechanisms, and many of the cities on this list have done so. It is important to note that the estimates published by the UCS do not take into account the mitigating effects of such mechanisms.
Correction: An earlier version of this piece attributed the $117.5 billion flooding estimate cost to Zillow. That estimate was calculated by the Union of Concerned Scientists.