Coastal flooding puts 20% of the world economy at risk by 2100, according to a new report

Residents take pictures and explore the catastrophic damage of downtown Sanford following extreme flooding across central Michigan on May 20, 2020 in Sanford, Michigan.

Matthew Hatcher | fake pictures

According to the new report published Thursday in Springer Nature, up to 20% of the world’s gross domestic product could be threatened by coastal flooding by the end of the century if measures are not taken.

The research, conducted by scientists at the University of Melbourne, found that an additional 287 million people, or 4.1% of the world’s population, could be at risk of coastal flooding by 2,100. Depending on the affected areas, this translates to $ 14.2 trillion worldwide, which is approximately one fifth of world GDP.

According to the study, areas in north-western Europe, as well as southeast and east Asia, are the most exposed, and areas in the northeast US and northern Australia are likely to be affected as well. .

To reach their conclusion, the researchers analyzed sea levels during extreme weather events and then compared these findings with projections of sea level rise. They then analyzed topographic data to determine the areas most at risk and analyzed population levels and the contribution of these regions to world GDP.

“The projected sea level rise will significantly increase the frequency of coastal flooding by 2100, with results showing that in most of the world, flooding associated with a current day 1 event in 100 years could occur as frequently as once in 10 years, primarily as a result of sea level rise, “the report said.

The scientists, led by Ebru Kirezci, discovered that if no changes are made, 48% more of the world’s land surface will be exposed to coastal flooding, resulting in a 52% jump in the exposed population. Of the coastal area at risk of flooding, 68% will be due to tides and storms, and 32% due to the projected rise in sea level.

“As approximately 600 million people live in low elevation coastal areas … the environmental and socio-economic impacts associated with episodic coastal flooding can be massive,” the report said.

Total assets exposed to coastal flooding will increase from 9% to 13% of current global GDP, to between 12% and 20% by 2100.

However, the researchers quickly realized that these results assume that no action is taken, meaning that their projections could be overstated. Nor did the report take into account changing GDP levels or future population projections.

“In many places, coastal defenses are commonly deployed and by 2100 adaptation and specifically tough protection are expected to become widespread, therefore these estimates should be seen as illustrations of the scale of adaptation necessary to offset the risk “the researchers wrote.

Of course, these measures don’t always end up working, like when New Orleans was devastated by Hurricane Katrina in 2005.

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