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Your Oceans, On Ice

NYT series examines how the world's coastal cities could be tied to the fate of Antarctica's ice sheet

"Spectacular sheer cliffs rising 100 feet above the ocean and extending 900 feet below the surface," is how journalist Justin Gillis describes Antarctica in his recent three-part series in the New York Times, "Antarctic Dispatches." This stunning monochromatic landscape is the result of millions of years of compacted snowfall, which has suppressed most of the topographic landmarks usually associated with a continent.

Antarctica is buried under an approximately two-mile deep ice sheet that has locked in about 60 percent of our planet's fresh water, and it's rapidly melting into the ocean. Based on the research’s implications for the future, surf communities will be the first affected — and, potentially, devastated.

In his piece, Gillis highlights radical climate change forecasts that predict potential sea level rise of 6 feet by the end of this century. A rise this extreme would be catastrophic for costal communities and cause millions of costal refugees. Fortunately, Gillis explains that this predication is still "considered crude, even by the researchers who created" it, and scientists are "racing against time" to narrow in on more accurate projection.

Why could the findings about Antarctica be so threatening? Unlike most of the Arctic ice, which is sea ice, the Antarctic ice is land ice, formed by millions of years of snow compaction on the continent. Just like how ice cubes in a glass don't raise the water line when they melt, sea ice obeys this same principle, because it already factors into our current sea level. However, when Antarctic ice falls into the sea, it can create drastic rises, because water is being added into the ocean.

In the piece, NYT designers Derek Watkins and Jeremy White create a graphic that illustrates the process of ice creeping across the ice sheet to the ice shelf.

“The event occurs when gravity pulls and stretches the ice, like honey, until it reaches the margins of the continent," says Dr. Till Wagner, a surfer and post-doctoral scholar at the Scripps Institution of Oceanography in San Diego.

Gillis explains how this ice shelf acts like a stopper that collects the ice runoff and inhibits it from reaching the ocean. As the ice creeps towards the coast, it hangs over the edge and forms an ice shelf that floats off its shore, kind of like how the coin pusher arcade game forms a shelf of tokens.

Just like the final token can cause several coins to fall, fatigue on the ice shelf from increased global temperatures and wave action can cause pieces of ice to crevasse, split from the shelf, and drift until they melt into the ocean. The common belief is that climate change is accelerating this fracturing via increased temperatures.

The acceleration of the fracturing can lead to a loss of the ice shelf, which would then directly accelerate the melting of the ice sheet by allowing the ice flows to run straight into the ocean, creating a disastrous feedback loop.

According to Gillis, evidence has emerged that the ice sheet has begun to retreat and destabilize. Since the 1990s, the rate at which, glaciers are dumping ice into the ocean has tripled, and more than 100 billion tons are lost each year, Gillis writes.

“We haven't seen anything with this speed and structure in the last 1,000 years,” says Dr. Sarah Gille, a professor of physical oceanography at Scripps. “We're trying to figure out what it means for costal communities. Flat beach cities are potentially really vulnerable, but everybody should be concerned."

One reason why it's difficult to accurately model climate change is because there are a lot of non-linear processes to consider; two degrees of warming doesn't necessarily mean one meter of melting, according to Dr. Wagner.

For example, if you think about a windy day, when it's white-capped, blown out, and the ocean is frothier than an IPA on tap, there are bubbles created that bring gas and heat into the ocean. But when it's slightly blowing offshore, Dr. Gille explains, the variables are not at all the same. Many different conditions are constantly occurring in the ocean, and Gille says we haven't observed them all perfectly in high latitudes.

Winds, eddies, currents, and submarine canyons are just some of the nuanced, complex, small-scale, long-term processes that are at play and are very uniquely specific to the Antarctic. Our lack of information on these processes creates the gaps in climate models.

Large pushes are being made to, "get the data needed to refine the forecasts and get ahead of the alarming changes already occurring in Antarctica," says Gillis. As isolated as Antarctica may seem, he writes, it's important to take small actions that can reduce our emissions and our carbon footprint in order to slow the process.

It's a difficult thing to communicate, Dr. Wagner explains, because, "weather is day to day," but climate is long-term.” He says that one thing is certain: sea level rise will change every surf break in the world. There’s at least a chance your grandchildren's favorite spot could be over your old downtown.