The impact of climate and demographic changes may make serious storms like Hurricane Katrina more frequent occurrences, according a recently published study.
The economic damage from hurricanes may quadruple by the end of the century as populations, global wealth and the temperature of the earth increase, according to research conducted by professors from Yale and MIT. The study, published Jan. 15 in Nature Climate Change, also concludes that the United States is uniquely vulnerable to the forecasted cyclones. The study’s authors cautioned that more research should be done before implementing any specific policy changes to deal with the increased destructiveness of hurricanes.
“This is the first real attempt to understand the influence of both demographic and climate change on hurricane damage,” said Kerry Emanuel, professor of atmospheric sciences at MIT and a co-author of the study. Robert Mendelsohn GRD ’78, a co-author of the study and economics professor at the Yale School of Forestry & Environmental Studies, added that unlike previous studies which separated economic and scientific analysis, this study established a new integration assessment model to best incorporate the scientific and economic data.
Emanuel led a team of researchers to predict how climate change might impact hurricane activity between now and 2100. They planted potential storms called “seeds” in four established climate prediction models that measure meteorological data to forecast where hurricanes will develop. The computerized models enabled the researchers to track the development, intensity and landfall site for each of the storms.
“A tropical storm is an engine that is based on the difference in temperature and humidity between the sea level and the upper atmosphere,” Mendelsohn said. “The sea is going to get warmer and the difference is going to get bigger.”
Mendelsohn’s team at Yale then used current data and demographic forecasts to calculate the economic damage of each hurricane. They also calculated the financial impact of forecasted hurricanes without climate change as a control group.
The results of the study indicate that while climate change will have little impact on small storms, large hurricanes may become more frequent and more intense. The model predicted that the hurricane landfalls in East Asia and along the North American coast will account for 88 percent of the forecasted damage. Both regions are characterized by dense population clusters in vulnerable coastal areas. The researchers determined that even without the anticipated climate change, the annual economic damages from hurricanes may more than double from $26 billion per year to $56 billion per year by 2100 as the global population increases to nine billion. With climate change, the researchers concluded that the damage may quadruple to $109 billion.
Roger Pielke, professor of environmental studies at the University of Colorado at Boulder, wrote in an email to the News that the paper serves as a “warning” to those who advocate for action against man-made climate change while ignoring social factors. He added that the study is “consistent” with the conclusions of his previous research: In a 2007 study Pielke concluded that climate stabilization policies, such as emissions reduction laws, have less potential to reduce future disaster losses than adaptive policies that could help to limit our vulnerability to hurricanes.
Emanuel also discussed the relationship between American policy and the forecasted damages, concluding that current policy encourages people to live in risky areas.
“Through capped insurance premiums, through federal bailouts in the form of disaster relief, through the provision of cheap insurance that covers floods, we make living in a dangerous place on the coast much, much cheaper than a free market would assume is reasonable,” Emanuel said. “We have guaranteed through policy that we will have a long string of Katrinas going forward in the United States.”
Since releasing the study, Emanuel has been criticized by a number of climate bloggers, including Steve Milloy, a commentator for Fox News and founder and publisher of junkscience.com, for failing to disclose a potential conflict of interest. Emanuel is a board member of the AlphaCat Fund, a subsidiary of the Bermuda-based Validus Managers Ltd. that invests in reinsurance transactions and catastrophe bonds.
Emanuel called the allegation a “baseless charge” and said that “there is no conflict of interest” because the board has not discussed climate change. Milloy did not respond to a request for comment from the News.
Both Mendelsohn and Emanuel acknowledge that the integration assessment model has room for improvement. For example, the current study does not account for the impact of rising sea levels or government adaptation policies. Mendelsohn stated that he plans to refine the model to study whether the United States’ policies make it more vulnerable to hurricane damage than other areas of the world.
Hurricane Irene, which struck New Haven on Aug. 28, 2011, is estimated to have affected at least 55 million people and caused between $7 billion and $10 billion in damages in the United States, according to the New York Times.