Galveston and 17 other Texas coastal towns are certain to lose land to rising sea levels at some undetermined point due to existing carbon emissions, at least one researcher says.
The research by Benjamin Strauss of the nonprofit organization Climate Central is depicted with an interactive map http://www.climatecentral.org/news/sea-level-rise-locking-in-quickly-cities-threatened-16296 that shows the relative speed and impact of climate change under the current trend compared with the outcome of making deep emission cuts.
Under the "current trend" scenario, 18 Texas towns, including Galveston, are already committed (by 2012) to being 25 percent below sea level at some future point, according to the map.
Nine cities and towns - a list that excludes Galveston but takes in Tiki Island - are already committed to being 50 percent under water at some point, given the current rate of emissions.
"As climate pollution grows, sea level debt - the long-run sea level rise we cannot avoid - is surging," states the text accompanying the map. "How many cities fall below the future tide depends on how much more carbon we put in the air."
The research doesn't address at what point the seas will rise to a particular level, Strauss said.
"Imagine you've dumped a bucket of ice on the table," he said as a comparison.
"It's very easy to know it's going to melt but harder to say exactly how fast it will melt," Strauss said. "This research is about the total amount of melt that will happen, not about the rate of melt."
Two important things stood out from the research, he said.
"One is the great speed with which we're racking up longterm consequences by continuing to put carbon in the atmosphere," he said. "Growing our commitments (to rising seas) by one foot a decade is really extraordinary to me."
The other major take-away from the research is the great difference that our future emissions will make, Strauss said.
"Even though hundreds of American towns and cities are already committed to watery futures, the amount of pollution we emit from here forward will make the difference for hundreds more," he said.
The Levermann paper was published online July 15 in the Proceedings of the National Academy of Sciences.