Coastal Damage Due to Sea Level Rise Could Cost as Much as 9% of Global GDP

Damage to coastal infrastructure due to flooding is expected to increase during the 21^st century as sea levels rise and development increases. A new report published in the Proceedings of the National Academy of Sciences (PNAS) finds that future damages could result in losses that will cost more than 9.5 percent of the global GDP.

Global climate scientists sought to quantify the impact of coastline destruction due to rising sea levels. They found that, by the end of this century, the costs could amount to more than nine percent of the global GDP. Projecting the costs of sea level rise is difficult because the height of seas will depend on the rate of warming and the amount of destruction will depend on whether we continue to build on coastlines.

Researchers used Space Shuttle data and satellite sensing to estimate the value of assets that could be destroyed by seal level rise. According to John Trimmer, science editor for Ars Technica, if we continue with our “business as usual” mentality, the costs could reach the high end of scientists’ estimate of losses of 1.2 percent to over 9.5 percent of the global GDP.

“The value of assets within the reach of a 100-year flood event will range between $17 trillion and $180 trillion by the end of the century – and that’s under an emissions scenario that’s unrealistically low,” Trimmer notes. “Under business-as-usual emissions… the figures will range from $21 trillion to $210 trillion… Even under the unrealistically low emissions scenario, the losses could reach up to five percent of the global GDP annually.”

The report provides a look at the potential scale of the problem facing countries if policies remain the same. In the United States, for example, some policy makers such as Texas’ Gov. Rick Perry continue to suggest that climate scientists have manipulated data regarding sea level rise.

In 2011, a report commissioned by Texas’ Commission on Environmental Quality (TCEQ) was censored to “tone down” its findings on the impact of climate change and sea level rise. John Anderson, the research scientist who was asked to write the report on sea level rise in Galveston Bay, told the Houston Chronicle that TCEQ deleted references to the impact humans have had on the environment and censored data on sea level rise.

Last year, lawmakers in North Carolina proposed a new law to require estimates of sea level rise to be based solely on historical data and not new evidence. The sea level along the North Carolina coast is expected to rise over 3 feet by the end of the century. But policymakers yielded to big business in the state by attempting to require inaccurate projections, Mother Jones reports.

Lawmakers in Virginia also altered a study to determine the impacts of climate change on the state’s shores, which cost the state $50,000 to commission. The Virginia legislature omitted words like “climate change” and “sea level rise” from the study’s description, ClimateProgress reports. Republican State Delegate Chris Stolle, who led the push for the changes, called “sea level rise” a “left-wing term” and said terms like “coastal resiliency” and “recurrent flooding” are “liberal code words.”

Alisha is a writer and researcher with Ring of Fire. You can follow her on Twitter @childoftheearth.