A recent study found that a warming climate may increase the frequency of intense hurricanes, resulting in a rise of hurricane damage costs on the order of tens of billions of dollars a year by 2100.
Changing demographics alone were found in the research to cause substantial changes in the future.
A collapsed house in North Carolina that could not withstand the 15-foot storm surge caused by Hurricane Floyd in 1999. Photo from NOAA.
Changing Demographics to Cause Increase in Hurricane Damage Cost
Changing demographics in the future are expected to lead to a significant increase in damage losses caused by hurricanes. While increasing value of coastal properties plays a role in hurricane damage costs, increasing development of coastal areas is momentous.
There have already been noted increases in population along both the Gulf and Atlantic coastlines of the U.S.
According to the U.S. Census Bureau in 2010, the population density increased by 32 percent along the Gulf Coast and 17 percent along the Atlantic coast from 1990-2008.
Many of the densely populated communities along the Atlantic and Gulf coasts are less than 10 feet above mean sea level, according to NOAA. This puts coastal communities at risk for storm surge damage on top of wind damage and flooding rainfall.
In addition, NOAA reports that more than half of the nation's "economic productivity" lies within coastal zones of the United States.
"We see changes [in hurricane damage costs] on the order of 50 percent or so over the next 100 years due to demographics alone," Kerry Emanuel, professor of Atmospheric Sciences at Massachusetts Institute of Technology, said.
Climate Change Influences on Hurricane Damage Costs
On top of changes in population near coastlines and other changes in demographics, the research performed by Emanuel found that climate change may have a profound impact on the cost of hurricane damage in the future.
"Globally, we actually expect the number of storms to decline. And that's because the middle part of the atmosphere, 2 or 3 miles above the surface, gets drier in a relative sense as the climate warms," Emanuel explained.
But while the overall frequency of storms may decrease, the frequency of more intense hurricanes may increase. This seeming discrepancy arises since the factors that influence the frequency of storms are different from those that influence the strength.
This photo of Tropical Storm Lee was captured by AccuWeather.com's Valerie Smock while on a hurricane hunter mission Saturday, Sept. 3, 2011. Lee was just offshore of Louisiana when this picture was snapped. For an account and more photos from Valerie's mission, click here.
"Now as you warm the climate, the driver for hurricanes, which is really that the sea surface becomes warmer and that allows hurricanes to become more intense," Emanuel added. "Most of the models show - in most but not all places - that the frequency of intense hurricanes goes up with a warming climate."
With an increase in stronger hurricanes, the study found that very large rises in damage costs from hurricanes may occur.
"We see changes - quite large potential changes - in hurricane damage [by 2100] on the order of tens of billions of dollars a year," Emanuel said.
Besides using theory to analyze how the frequency and intensity of hurricanes will be effected by climate change, Emanuel utilized a technique called "downscaling." He embedded high resolution, specialized hurricane models into four different global climate models.
The uncertainty of the damage cost of hurricanes in the future, factoring in climate change, was described by Emanuel as "a great deal."
"Of the four models, one produces essentially no change at all, two models produced a change on the order of 20 billion dollars a year and the fourth model produces a change of almost 70 billion dollars a year," Emanuel added.
Implications of the Research
People and organizations who need to make long-term plans such as building seawalls or levee systems can use the results of Emanuel's research.
"The city of New York needs to decide whether and how much to spend on seawalls that might help protect New York City from storm surges," Kerry said, giving an example of the implications of his research. "Now, storm surges are interesting. They are one of the major sources of damage caused by hurricanes. They are like tsunamis but they are not generated by earthquakes but by hurricane winds. But you have a twin problem because not only do you have a greater potential incidence of stronger storms in New York City, but the storm surge is riding on a sea level which is elevated because of climate change. So, the twin perils combine in this case."
"So, if you want to build a seawall, you're thinking on a 50-year time scale or maybe even 100-year time scale. You want that seawall to last a long time and you have to decide how high to make it and how strong to make it."
Emanuel also gave the example of the World Bank, explaining that knowing the financial demands that might be caused by climate-related damages, would be very useful.
On the other hand, an organization such as an insurance company need to know information on a much shorter time scale.