Quantcast
Environmental News for a Healthier Planet and Life

As Sea Levels Rise, Coastal Cities Face Flood Damage Exceeding $1 Trillion

Climate
As Sea Levels Rise, Coastal Cities Face Flood Damage Exceeding $1 Trillion

Climate News Network

By Tim Radford

By 2050, flood damage in the world’s coastal cities is expected to reach $1 trillion a year as sea levels rise and global warming triggers new extremes of heat, windstorm and rain.

More than 40 percent of these prodigious costs could fall upon just four cities—New Orleans, Miami and New York in the U.S. and Guangzhou in China.

Stephane Hallegatte of the World Bank in Washington and colleagues looked at the risks of future flood losses in the 136 largest of the world’s coastal cities.

Any coastal city is always at some risk—by definition it is at sea level, and often on an estuary or floodplain, and very often began as a seaport.

But risks increase as the environment changes: some coastal cities are subsiding; sea levels are slowly but surely rising as the oceans warm and the glaciers melt; and for two decades researchers have repeatedly warned that what used to be “extreme” events such as once-in-a-century floods are likely to arrive considerably more often than once a century.

But, Hallegatte and colleagues point out in Nature Climate Change, there is another factor: populations are growing, and even in the poorest nations there is greater economic development. At bottom, for any future disaster, there will be more potential victims, with more investment to lose.

In 2005, average global flood losses are estimated to have reached $6 billion a year. This figure is expected to grow to $50 billion a year, and unless cities put money into better flood defenses, losses could pass the $1 trillion mark.

To make their calculations, the authors matched average annual losses (and in a city like New Orleans, much of it already below sea level, this is estimated at $600 million) against a city’s gross domestic product, to provide a measure of how much should be set aside to pay for such losses.

Both New York and New Orleans have already undergone catastrophic flooding this century, and flood hazard can only increase.

Some cities—Amsterdam in the Netherlands is a classic example—are highly exposed to flood risk, and the once-a-century flood could cost the Dutch $83 billion, but in fact Dutch sea defense standards are probably the highest in the world. Ho Chi Minh City in Vietnam and Alexandria in Egypt have less to lose, but in relative terms both are far more vulnerable.

Prophecies such as these are intended to be proved wrong: the idea is that a prophet warns of horrors to come, people take steps and as a consequence the horrors do not arrive.

But as disaster professionals have learned again and again, governments, city authorities, investors and even citizens tend not to listen to prophecies of doom: scientists and engineers repeatedly described what could happen to New Orleans if it was hit by a powerful-enough hurricane, and in 2005, as Hurricane Katrina arrived, the levees gave way with catastrophic results.

But, the scientists warn, Miami, New York and New Orleans are especially vulnerable, because wealth is high but protection systems are poor, and governments should be prepared for disasters more devastating than any experienced today.

The paper’s authors argue that with systematic preparedness and adaptation, annual flood losses in the great global cities could be cut to $63 billion a year.

Engineering projects can help, but will not be enough, so civic authorities should also be thinking about disaster planning and comprehensive insurance programs to cover future losses.

Since risks are highly concentrated—any city piles millions of people and billions of dollars of investment into a relatively small area—flood reduction schemes could be highly cost-effective.

Visit EcoWatch’s CLIMATE CHANGE page for more related news on this topic.

——–

A view of the Arctic National Wildlife Refuge during Arctic Bird Fest on June 25, 2019. Lisa Hupp / USFWS

By Julia Conley

Conservation campaigners on Thursday accused President Donald Trump of taking a "wrecking ball" to the Arctic National Wildlife Refuge as the White House announced plans to move ahead with the sale of drilling leases in the 19 million-acre coastal preserve, despite widespread, bipartisan opposition to oil and gas extraction there.

Read More Show Less

EcoWatch Daily Newsletter

The Bond Fire, started by a structure fire that extended into nearby vegetation on Thursday, Dec. 3, 2020 in Silverado, CA. Kent Nishimura / Los Angeles Times / Getty Images

Hot, dry and windy conditions fueled a wildfire southeast of Los Angeles Thursday that injured two firefighters and forced 25,000 to flee their homes.

Read More Show Less

Trending

Hospital workers evacuate patients from the Feather River Hospital during the Camp Fire on Nov. 8, 2018 in Paradise, California. People in 128 countries have experienced an increased exposure to wildfires, a new Lancet report finds. Justin Sullivan / Getty Images

The climate crisis already has a death toll, and it will get worse if we don't act to reduce emissions.

Read More Show Less
Workers harvest asparagus in a field by the Niederaussem lignite coal power plant in Cologne, Germany. Greenhouse gas emissions from fossil fuel burning are reaching new highs. Henning Kaiser / picture alliance via Getty Images

By Stuart Braun

The UN Secretary-General Antonio Guterres addressed the dire threat of climate change Wednesday in a speech on the state of the planet delivered at Columbia University in New York.

Read More Show Less
The miserable ones: Young broiler chickens at a feeder. The poor treatment of the chickens within its supply chain has made Tyson the target of public campaigns urging the company to make meaningful changes. U.S. Department of Agriculture / Flickr

By David Coman-Hidy

The actions of the U.S. meat industry throughout the pandemic have brought to light the true corruption and waste that are inherent within our food system. Despite a new wave of rising COVID-19 cases, the U.S. Department of Agriculture recently submitted a proposal to further increase "the maximum slaughter line speed by 25 percent," which was already far too fast and highly dangerous. It has been made evident that the industry will exploit its workers and animals all to boost its profit.

Read More Show Less