Avoiding the next Katrina: preparing for sea-level rise in the U.S.

Sea-level rise poses a threat to America's coastal populations. The rate of sea-level rise has increased over the past few decades, and future warming will cause the Earth's average sea level to rise another half meter by the year 2100. Extreme weather events, including hurricanes, floods, and storms are sure to accompany this rise. While a lot of research has already shown that coastal areas and low-lying lands are vulnerable, little attention has been paid to how specific populations will be affected in light of population trends and changing social landscapes.
 
A pair of researchers from the University of Wisconsin-Madison has examined four of the most vulnerable coastal regions of the U.S. They looked at population growth and immigration trends with climate change predictions to see which counties would be most affected by the year 2030, and how badly they would be affected. Their findings, published in Population and Environment, show that the impacts of sea-level rise will vary regionally because of both geography and social make-up. They also conclude that the preparation should be undertaken at the county level because the scale of the stress will call on local resources and knowledge.
 
Sea-level rise will be felt far beyond the coasts. The effects of a rising tide will spread outward as coastal communities follow migration routes inland. The authors make it clear that more research is needed at a finer scale because each area has a particular set of social groups with its own human dimensions. The authors found that threats to Hispanic communities and valuable farmland will be the main threat for California, for instance, while in Florida, the contamination of freshwater and threats to immigrants and elderly people are set to occur. Meanwhile, in New Jersey, the dense and ethnically diverse and urban areas lie on vulnerable floodplains, and in South Carolina, where rural and poor areas are under threat, the main issues will be soil erosion, freshwater contamination, and threats to African-American communities.
 
The case of Katrina is a rallying point for preventative action. Indeed, the authors show that their study would have pointed to New Orleans as one of the most vulnerable coastal regions in the country. Forecasts such as these will be invaluable in preparing for disasters and avoiding the costs of delay. The authors recommend that preparation should be improved at the county level because those policymakers are best suited to deal with the capacity and infrastructure issues that will be involved. Although there is no blanket solution for coastal area protection, the shared problem of rising tides and rising public costs are sure to demand much from America's local leaders.