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Disquiet on the Hurricane Front

[This op-ed by Dan Sarewitz and Roger Pielke, Jr. on the 2006 hurricane season was not published by a number of major newspapers. So we are happy to share it here. Anyone interested in publishing it before a wider audience, please send us an email. -Ed.]

The 2006 hurricane season has ended without a single hurricane landfall along the Gulf or East coasts. In the wake of Hurricane Katrina and the destruction of New Orleans, journalists, politicians, and even some scientists were proclaiming that the catastrophe of global warming was upon us. A quiet year later, perhaps there is some room for clearer thinking about hurricanes, about global warming, and about society’s vulnerability to climate.

Before this year, the last years without a U.S. hurricane landfall were 2000 and 2001, just a blink of an eye in climate terms, but an eternity in the politics of global warming. In all, hurricane behavior over the past century and more has been highly variable, with periods of great intensity followed by lulls. Scientists remain deeply divided about the role of greenhouse gas emissions in hurricane behavior. But scientists have appreciated for decades the inevitability of a Katrina-like hit on New Orleans. The city was doomed for reasons that have nothing at all to do with global warming: it lies on a subsiding river delta in the heart of hurricane country.

Increasing damages from U.S. hurricane landfalls in the U.S. over the past century are entirely explained by growing socioeconomic vulnerability—that is, by coastal development trends that continually expose more people, more infrastructure, and more economic activity, to hurricanes. If one accounts for the effects of socioeconomic change, then there has been no observable increase in U.S. hurricane damage since data were first collected in 1900.

The future may indeed hold more frequent or intense hurricanes. However, the science at this point shows unambiguously that the effects of any such changes in storm behavior will be completely dwarfed by the effects of continued coastal development.

As Katrina made devastatingly clear, the hurricane problem is one of unsustainable coastal development combined with unconscionable socioeconomic vulnerability. Katrina’s blood relatives are the 2004 south Asian tsunami (220,000 dead) and the 2005 Pakistan earthquake (80,000 dead), not the Earth’s slowly warming atmosphere.

Feel-good appeals to buy hybrid vehicles cannot reduce the entrenched social inequities, irresponsible development trends, and inadequate hazard reduction policies that led to the worst of Katrina’s depredations and that are the cause of rising disaster vulnerability worldwide. Neither can the Kyoto Protocol, carbon trading markets, or other energy policies. There is simply no evidence that reductions in greenhouse gas emissions—as important as they are for other reasons—will lead to any discernible reduction in hurricane impacts over the next 50 to 100 years. Reducing greenhouse gas emissions is about as relevant to controlling the impacts of hurricanes and other natural disasters as a nuclear non-proliferation treaty is to protecting public health.
Yet many well-tested policies are available to help reduce vulnerability to natural disasters. These range from building codes that can keep structures from collapsing in a storm or earthquake, to land use regulations that limit construction in disaster-prone areas, to environmental laws that preserve natural features, such as wetlands and forested slopes, that act as buffers against extreme events. The rising toll of disasters around the world demonstrates that nations are greatly underinvested in applying such policies, despite the fact that they are known to be effective, and despite the certainty that more disasters will soon occur.

From a political perspective, it is tempting to exploit the tragedy of Katrina and other natural disasters to promote action on greenhouse gas reductions. But no matter how strongly advocates may feel about global warming, if climate policies are based on the false expectation that emissions reductions will reduce hurricane losses, then political failure is inevitable, because the problem will get worse, not better. (To grasp this point, just consider the political impact of falsely linking Iraq to terrorism).

During this quiet hurricane season, more people moved to the coasts and other locations vulnerable to disasters, ensuring that future losses will be larger than those of the past. At the same time, more carbon dioxide and other greenhouse gases were emitted into the atmosphere. These are separate problems that demand separate solutions. But by turning hurricanes into a greenhouse gas problem, we fail to focus sufficient attention and resources on reducing disaster vulnerability, and thus turn our backs on the victims of future disasters as well.