Have Insurers Begun to Detect Climate Change in Storm Damage?

It's likely that the number of strong storms involving rain, snow and hail is also rising because of warming temperatures, not just urban sprawl and expanding development


On supporting science journalism

If you're enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.


The United States was struck by more natural disasters last year than ever before, with 247 blizzards, thunderstorms and floods accounting for a record level of frequency partly attributable to climate change, according to a major reinsurance company.

About 150 of the events were rainstorms and snowstorms, showcasing the rising number of meteorological disasters that are pelting the United States. In 1980, for example, when total disasters barely reached 60, the number of damaging storms was just over 50.

Nearly 190 Americans died in thunderstorms, blizzards and floods last year, all of which cost the country tens of billions of dollars in damages. The price to insurance companies for thunderstorm damage alone amounted to more than $9 billion, underscoring a 500 percent rise in the average yearly loss from that peril since 1980.

Those sky-climbing costs are mostly caused by people, not climate change, cautions Munich Reinsurance, which says urban sprawl and expanding development increase the number of targets for Mother Nature to damage.

A larger human footprint can also increase the frequency of events. Disasters can't be observed if no one is there to see them.

But it's likely that the number of strong storms involving rain, snow and hail is also rising because of warming temperatures, says Ernst Rauch, who heads the company's Corporate Climate Center.

"We believe we see indications that weather patterns -- so the frequency and intensity of convective storms -- in some parts of the United States has already changed," he said yesterday. "So we believe we have indications that climate change is already, at least to some extent, visible."

Heat and water: a dangerous combination
Last year began, and ended, in a whipping blanket of white. Blizzards buried Eastern cities in February, then returned in December to harass New York City and elsewhere. Wintertime disasters killed 64 people in 2010 and caused $2.6 billion in insured losses, Munich Re reports.

Major floods, meanwhile, inundated streets and buildings in New England and Tennessee last spring. Those and other floods killed 68 people and soaked insurers for about $1 billion.

Still, even as the United States saw more disasters, the damage they inflicted was below the 10-year average. That's almost entirely due to the fact that an army of tropical storms marched over the ocean, not onto U.S. beaches.

Worldwide, disasters have doubled in 30 years, from less than 400 in 1980 to 950 last year. That's the second-highest number of events recorded by Munich Re since 1980.

The toll is enormous. An earthquake on Jan. 12, 2010, in Haiti killed 222,570 people and caused $8 billion in economic losses, of which just $200 million was insured.

A sizzling heat wave in Russia killed 56,000 people. A week of heavy rains inundated Pakistan with floodwater, killing 1,760 people. It's difficult to ascertain the impact of rising temperatures on those connected events, but climate change in the future is expected to have its fingerprints on dueling droughts and floods.

Low rate of hurricane landfalls may not last
Researchers say heavier downpours are already occurring in the United States. More moisture is able to build up in the warming atmosphere, and when it's released, more falls to the ground. But the time between rainfalls might be longer, contributing to drought.

"If you pull more water out, it will take longer to recharge," said Harold Brooks, a research meteorologist with the National Severe Storms Laboratory in Oklahoma. "That's why we get both flood and drought [with climate change]."

In the United States, disaster damages were manageable last year when compared to what could have happened. Although 2010 was packed with swirling tropical storms and hurricanes, all but one -- Tropical Storm Bonnie -- stayed out to sea.

That low level of landfall activity has only happened nine times since 1900, said Carl Hedde, head of risk accumulation at Munich Reinsurance America.

As a result, the nation suffered about $13.6 billion in insured losses during the first six months of last year, the most currently available statistics, according to Robert Hartwig, president of the Insurance Information Institute. That's 19 percent below the figures for a year earlier.

But that's all due to change eventually, he warns, when Miami or another city is struck by a mega-hurricane, causing perhaps $100 billion in damage.

"Quite frankly, I think the United States dodged a bullet last year," Hartwig said.

Reprinted from Climatewire with permission from Environment & Energy Publishing, LLC. www.eenews.net, 202-628-6500

It’s Time to Stand Up for Science

If you enjoyed this article, I’d like to ask for your support. Scientific American has served as an advocate for science and industry for 180 years, and right now may be the most critical moment in that two-century history.

I’ve been a Scientific American subscriber since I was 12 years old, and it helped shape the way I look at the world. SciAm always educates and delights me, and inspires a sense of awe for our vast, beautiful universe. I hope it does that for you, too.

If you subscribe to Scientific American, you help ensure that our coverage is centered on meaningful research and discovery; that we have the resources to report on the decisions that threaten labs across the U.S.; and that we support both budding and working scientists at a time when the value of science itself too often goes unrecognized.

In return, you get essential news, captivating podcasts, brilliant infographics, can't-miss newsletters, must-watch videos, challenging games, and the science world's best writing and reporting. You can even gift someone a subscription.

There has never been a more important time for us to stand up and show why science matters. I hope you’ll support us in that mission.

Thank you,

David M. Ewalt, Editor in Chief, Scientific American

Subscribe