Antarctic Ice Report Shows the Future We Can't Change

The University of Arizona’s Department of Geosciences

Two groups of scientists are reporting this week that the West Antarctica Ice Sheet has already begun to melt and has passed "the point of no return." That means that current Intergovernmental Panel on Climate Change projections for sea level rise are too low. Sea levels may, in fact, rise by between 10 and 32 inches by the end of the century—and more in subsequent centuries.

In other words, those who live on coastlines—or their children and their children's children, more accurately—will have to contend with an unprecedented rise in sea levels caused by human-driven climate change.

And if the reports are correct, those trends are irreversible.

"The thing that's scary about this is, there's nothing that can be done to stop it now," Dr. Tim Barnett, a research marine physicist at the Scripps Institution of Oceanography, told Newsweek. "We're in for it. If it happens in 200 years or 100 years or whatever, it's almost with certainty going to happen."

So which U.S. locations are going to be affected the most? Stateside, "major cities like New Orleans, Miami, Tampa, Charleston and Virginia Beach are among those at greatest risk, but there are many others," said Dr. Virginia Burkett, the chief scientist for climate and land use change for the U.S. Geological Survey. The list includes low-elevation coastal zones, areas that are sinking and those already prone to flooding. "Those areas that are already below sea level, like New Orleans, are particularly vulnerable," she said.

A National Oceanic and Atmospheric Administration map shows the most vulnerable locations in the U.S. based on a Coastal Vulnerability Index:

National Oceanic and Atmospheric Administration

Meanwhile, the North Alaskan coast will be especially affected, Burkett said, "because sea level is rising, the ice that binds the coastal sediments is melting, and the sea ice that once protected the coast from erosion is retreating rapidly."

Barnett points to the Gulf Coast, Florida and New York. "Anyone that has a big continental shelf is going to be impacted," he said.

In the coming century, tri-state area commuters to New York City, for instance, may need to change their travel plans. Sea levels need only rise by 2.5 feet, a low estimate, for major portions of Metro-North's railroad track to be underwater at high tide. Hurricane Sandy, which left half the Hudson Line underwater, offered a preview of that scenario.

The University of Arizona's Department of Geosciences, meanwhile, has a visualization tool for mapping areas affected by the rise of sea levels. Here's how vulnerable New York City and parts of New Jersey will be if the level rises up to two meters:

The University of Arizona’s Department of Geosciences

Take a look at how the area surrounding Charleston Harbor in South Carolina will fare:

The University of Arizona’s Department of Geosciences

And here's Tampa and Saint Petersburg, Florida:

The University of Arizona’s Department of Geosciences

If the trends can be reversed, how can officials and people living in these locales (or anywhere, really) make use of the data? The answer: adaptation to minimize the adverse impact of rising sea levels.

"There are many things that coastal counties around the United States are experimenting with or have already employed," Burkett said. "One is to elevate bridges. If you're planning a bridge or restoring a bridge, they can raise the elevation of the bridge to accommodate higher sea level."

Protecting and restoring coastal barriers is another tactic to help increase the resiliency of coastal landforms and communities, she said. But that requires politicians to take the threat of global climate change seriously.

"This is very tangible: Here you go, politicians, stop arguing and get your act together, and let's do what we can to ameliorate the problem," Barnett said. "If that doesn't scare the hell out of you, I don't know what would."