Residents take photos and explore the catastrophic damage to downtown Sanford after extreme flooding in central Michigan on May 20, 2020 in Sanford, Michigan.
Matthew Hatcher | Getty Images
According to a new report published in Springer Nature on Thursday, up to 20% of global gross domestic product could be threatened by coastal flooding by the end of the century if no action is taken.
Research conducted by scientists from the University of Melbourne showed that by 2100 another 287 million people, or 4.1% of the world's population, could be at risk of coastal flooding. In terms of the affected areas, this equates to $ 14.2 trillion worldwide, which is about a fifth of global GDP.
Areas in northwest Europe and southeast and east Asia are most at risk, with areas in the northeastern United States and northern Australia also likely to be affected.
To arrive at their conclusion, the researchers analyzed the sea level during extreme weather events and compared these results with rising sea level projections. They then examined topographical data to identify the most vulnerable areas and analyzed the population level and the contribution of these regions to global GDP.
"The projected sea level rise will significantly increase the frequency of coastal flooding by 2100. The results show that in most parts of the world floods associated with an event of 1 in 100 years today, mainly once in 10 years can occur as a result of rising sea levels, "the report says.
Scientists led by Ebru Kirezci found that 48% more land in the world will be exposed to coastal flooding if no changes are made, which corresponds to a 52% increase in exposed population. Of the coastal areas at risk of flooding, 68% will come from tides and storms, 32% from the projected sea level rise.
"With approximately 600 million people living in low-lying coastal areas … both the environmental and socio-economic impacts of episodic coastal flooding can be massive," the report said.
Total assets exposed to coastal flooding are expected to increase from 9% to 13% of global GDP to 12% to 20% by 2100 today.
However, the researchers quickly found that these results assume that no action will be taken, which means that their projections may be overrated. The report also did not take into account changes in GDP or future population projections.
"Coastal defenses are widely used in many places, and adaptation and especially hard protection are expected to be widespread by 2100, so these estimates must be seen as examples of the extent of adaptation required to offset the risk," wrote Researchers .
Of course, these measures don't always work, for example when New Orleans was devastated by Hurricane Katrina in 2005.
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