If Unchecked, Storm Surge Flooding Will Cause Trillion of Dollars in Damage This Century

Throughout the course of the 21st century, storm surge flooding will cause trillions of dollars in damage to the world's coastal regions unless protective measures are put in place, according to a new report published in the Proceedings of the National Academy of Sciences.

Currently, economic damages from storm surge flooding average between $10-$40 billion globally each year. But new research from the Berlin-based think-tank Global Climate Forum (GCF) and the University of Southampton suggests that if no action is taken, damages from storm surge flooding will rise to as much as $100,000 annually.

Storm surge flooding is exacerbated by rising sea levels linked to climate change. Coupled with increases in population and economic growth in coastal regions expected as the century progresses, the potential for huge amounts of economic damage is worrisome, the researchers said.

If no adaptive action is taken, the researchers report up to 600 million people could be affected by coastal flooding by the end of the century.

"If we ignore this problem, the consequences will be dramatic," said lead study author Jochen Hinkel from GCF.

"Countries need to take action and invest in coastal protection measures, such as building or raising dikes, amongst other options," Hinkel said. "With such protection measures, the projected damages could be reduced to below $80 billion per year during the 21st century. The researchers found that an investment level of $10 to $70 billion per year could achieve such a reduction. Prompt action is needed most in Asia and Africa where, today, large parts of the coastal population are already affected by storm surge flooding."

But Asia is not the only high-risk area. Europe as well is expected to to be affected by an increase in storm surge flooding.

"If we ignore sea-level rise, flood damages will progressively rise and presently good defenses will be degraded and ultimately overwhelmed. Hence we must start to adapt now, be that planning higher defenses, flood proofing buildings and strategically planning coastal land use," said study co-author Robert Nicholls, of the University of Southampton.

The researchers report that strategic, long-term planning will ensure that development in high-risk flood zones is appropriately designed or avoided, but it may be a difficult goal to achieve when real estate developers focus on short-term profits rather than what's best for a population in the long run.

"This long-term perspective is, however, a challenge to bring about, as coastal development tends to be dominated by short-term interests of, for example, real-estate and tourism companies, which prefer to build directly at the waterfront with little thought about the future."