The upper bound of seal level rise (SLR) that doubles the exceedance probability of the former 50-year water level. This SLR is the upper limit of a 95 percent confidence interval based on a Monte Carlo simulation of the GEV parameter estimates and their associated confidence bands. Red areas represent regions particularly vulnerable to small amounts of SLR. Graphic: Vitousek, et. al, 2017 / Scientific Reports

By Dino Grandoni
22 May 2017
(The Washington Post) – On Thursday, a group of scientists, including three working for the U.S. Geological Survey, published a paper that highlighted the link between sea-level rise and global climate change, arguing that previously studies may have underestimated the risk flooding poses to coastal communities.However, three of the study’s authors say the Department of Interior, under which USGS is housed, deleted a line from the news release on the study that discussed the role climate change played in raising Earth’s oceans.“While we were approving the news release, they had an issue with one or two of the lines,” said Sean Vitousek, a research assistant professor at the University of Illinois at Chicago. “It had to do with climate change and sea-level rise.”“We did end up removing a line,” he added.Vitousek and five co-authors wrote the study, which was published in the journal Nature Scientific Reports. Three of the authors worked for USGS and the other three worked for universities.That deleted line, they said, read: “Global climate change drives sea-level rise, increasing the frequency of coastal flooding.” […]“It’s a crime against the American people,” Neil Frazer, a geophysics professor at University of Hawaii at Manoa and one of the study’s co-authors, said of the line’s removal and of other efforts to limit scientific communication from federal agencies. “Because scientists have known for at least 50 years that anthropogenic climate change is a reality.”He added: “The suppression of this information is a scandal.” [more]

Interior Department agency removes climate change language from news release

ABSTRACT: Global climate change drives sea-level rise, increasing the frequency of coastal flooding. In most coastal regions, the amount of sea-level rise occurring over years to decades is significantly smaller than normal ocean-level fluctuations caused by tides, waves, and storm surge. However, even gradual sea-level rise can rapidly increase the frequency and severity of coastal flooding. So far, global-scale estimates of increased coastal flooding due to sea-level rise have not considered elevated water levels due to waves, and thus underestimate the potential impact. Here we use extreme value theory to combine sea-level projections with wave, tide, and storm surge models to estimate increases in coastal flooding on a continuous global scale. We find that regions with limited water-level variability, i.e., short-tailed flood-level distributions, located mainly in the Tropics, will experience the largest increases in flooding frequency. The 10 to 20 cm of sea-level rise expected no later than 2050 will more than double the frequency of extreme water-level events in the Tropics, impairing the developing economies of equatorial coastal cities and the habitability of low-lying Pacific island nations.

Doubling of coastal flooding frequency within decades due to sea-level rise