Coastal flooding could threaten up to 20% of global GDP

Coastal flooding events could threaten assets worth up to 20% of the global gross domestic product (GDP) by 2100, which equates to 14.2 trillion US dollars.

08/21/2020 | 9:31 AM

This is according to a study by IVM researcher Sanne Muis and fellow authors published in the scientific journal Nature’s Scientific Reports.

Major consequences for world population and economy
Flooding events cause millions to billions of euros damage worldwide every year. The areas predicted to be most impacted by increased coastal flooding are, according to the authors, Northwest Europe (including the UK, northern France and northern Germany), Southeast and Eastern Asia, Northeast USA (including Virginia and Maryland) and Northern Australia. The findings indicate that without investment in flood defences or a reduction in greenhouse gas emissions, coastal flooding could have major consequences for the global population and economy by the end of the century. 

Under conditions of high greenhouse gas emissions and assuming no flood defences, the authors estimate that the land affected by coastal flooding could increase by 48% by the end of the century. This is caused by tides and storms, but also as a result of expected regional sea level rise. The authors suggest that the global population exposed to coastal flooding could be up to 287 million by the year 2100 (4.1% of the world’s population). 

Identification of maximum sea levels and risk areas
The authors combined global data on water levels during extreme storms with projections of sea-level rise under different climate scenarios. They used these data to model maximum sea levels that may occur by 2100. The researchers combined their model with topographic data to identify areas at risk of coastal flooding. Using data on global population distribution and GDP in affected areas, they were able to estimate the population and assets at risk from flooding.