Over the next 100 years, rapid sea level rise will change the landscape of the U.S. and increase the risk of severe flooding for thousands of households. According to the worst-case scenario in a new report by the Union of Concerned Scientists, about 180 U.S. communities will face chronic flooding by 2035.
Louisiana and Maryland will be home to 70% of these areas. In these states, land subsidence, which is the loss of elevation due to movements below the surface, is adding to the rapid rates of an increase in sea levels, according to the report, “When Rising Seas Hit Home: Hard Choices Ahead for Hundreds of US Coastal Communities.’’ More than half of the affected communities are home to one or more socioeconomically vulnerable neighborhoods.
According to the report, low land elevation and high rates of land subsidence are the two common features in most of these communities.
Chronic inundation is defined as flooding that occurs 26 times per year or more. Communities where more than 10% of usable land exceeds this threshold are considered chronically inundated.
The worst-case scenario assumes rising carbon emissions and rapid ice sheet loss over the 21st century, leading to a global average rise of 6.6 feet above 1992 levels by the end of the 21st century.
In the report, the UCS intend to highlight what is at stake in regard to addressing sea level rise and global warming. How much the sea level rises this century depends on past and future emissions of heat-trapping gases as well as how the Earth and the atmosphere respond to those emissions.