Published On: Thu, May 10th, 2018

Here’s what vanishing sea ice in the Arctic means for you


As the world’s temperatures go up, the Arctic keeps losing its ice. This winter, the area covered by sea ice was the second smallest on record — after last year. And many experts believe that this summer, the Arctic ice cap will shrink to record lows. Why should I care, you ask?

“The Arctic is a natural freezer,” says Michael Mann, a climatologist and director of the Earth System Science Center at Pennsylvania State University, in an email to The Verge. “Just like you’d be concerned if all of the ice in your freezer melted, so should you be concerned about the loss of Arctic sea ice.”

The changes that are happening in the Arctic don’t just affect the Arctic. Our planet is an interconnected system, and the vanishing ice is already having ripple effects down south. Among them: faster global warming, rising sea levels, and possibly more extreme natural disasters. (Plus, the polar bears will suffer.) Scientists are still trying to figure many things out, but pretty much everyone agrees that a melting Arctic isn’t a good thing.

“This whole climate change is a big can of worms,” says Ignatius Rigor, coordinator of the International Arctic Buoy Program at the University of Washington. “It’s pretty scary because we’re starting to realize more and more how big of an impact we’re having on the planet.”

So here are some ways that the vanishing Arctic ice is affecting the rest of the world — you included.

The albedo effect

The albedo effect is just a fancy expression for a very simple concept: white surfaces like ice and snow reflect about 80 percent of the Sun’s energy back into space. That allows us to keep cool. But if those white spots disappear, the darker ocean and land will absorb 90 percent of that heat, accelerating global warming. “If you have a black car, it gets hotter in the summer than if you have a white car,” says Peter Wadhams, professor of ocean physics at the University of Cambridge.

The albedo effect due to vanishing sea ice is already responsible for about 25 percent of global warming, according to Jennifer Francis, a research professor at Rutgers University’s School of Environment and Biological Sciences. So we’re all getting hotter because sea ice is shrinking, and the Arctic is warming up twice as fast as the rest of the world. That, in and of itself, can lead to even more problems.

Sea level rise

Sea ice floats, so when it melts, it does not raise sea levels. But warmer temperatures in the Arctic are causing another type of ice to disappear as well: land-based ice in Greenland. If that ice melts, it causes sea levels to go up. Scientists estimate that if the entire Greenland ice sheet — which is roughly three times the size of Texas — melted, sea levels would soar 20 feet.

The seas are already rising, and so far, Greenland has contributed to only 4 to 5 percent of that rise, says Francis. But melt rates are accelerating, and that poses a serious threat to anyone living on the coast. In the US, that’s about 40 percent of the population. Residents in Florida, New Jersey, and Maryland are already experiencing more flooding. And the situation isn’t going to get better.

“Certain cities will have to be abandoned,” Wadhams says. Rigor agrees: “Our coastal towns aren’t really built for this.”

In Alaska, there’s also another problem tied to vanishing sea ice. The ice protects coastal towns from big waves, Rigor says. Just this winter, as ice in the Bering Sea shrunk to record levels, huge waves pummeled the town of Diomede, engulfing homes. Erosion is also forcing the 400-plus residents of Newtok, Alaska, to relocate.

More extreme weather

There’s another way that a warming Arctic might hit close to home: many scientists believe that it might affect extreme weather events in North America and Europe. Earlier this year, for instance, research showed that when the Arctic is unusually warm, extreme winter weather is two to four times more likely in the eastern US.

That may be happening because a warming Arctic disrupts the jet stream, “a river of fast-moving wind high over our heads” that “basically controls and creates all the weather that we experience,” Francis says. The difference in temperature between the Arctic and the mid latitudes, where we live and it’s warmer, is one of the driving forces of the jet stream. But as the vanishing ice is causing the Arctic to warm twice as fast as the rest of the world, that temperature difference is diminishing. And that’s weakening the winds in the jet stream, Francis says. A weaker jet stream also has more waves, and that means more extreme weather that lingers for longer.

Francis says we’ve already seen this jet stream disruption in action this winter, as the eastern US experienced record-breaking freezing temperatures, a “bomb cyclone,” and three nor’easters in just 11 days. But others say there’s still “a lot of debate in the scientific community” on whether or not a warming Arctic is to blame, according to Julienne Stroeve, professor of polar observation and modelling at University College London.

More research is looking into this. And it’s not just about the US or Europe. A study in 2017 showed that there’s a link between shrinking Arctic ice and a build-up of smog in China.

Thawing permafrost

Rising temperatures in the Arctic are also causing frozen ground, called permafrost, to thaw in Alaska, Canada, and Siberia. That’s concerning because permafrost traps huge amounts of carbon — at least as much carbon as it’s in the atmosphere right now, Francis says. If the permafrost warms up, it can start releasing this carbon in the form of two powerful heat-trapping greenhouse gases, methane and carbon dioxide, making global warming worse.

One study published in Nature Geoscience in 2012 estimated that thawed permafrost could contribute up to 3 degrees Fahrenheit (1.7 degrees Celsius) of warming by 2300. That may not seem like much, but most scientists believe that we need to keep warming well below 3.6 degrees Fahrenheit (2 degrees Celsius) if we want to stave off the worst effects of climate change. And the greenhouse gas leak from the permafrost is independent from all the carbon dioxide we keep pumping into the atmosphere by burning fossil fuel. Those CO2 concentrations aren’t going down.

Wadhams says that offshore permafrost also poses a danger: the frozen, underwater sediments in the Arctic are rich in methane, and if those layers start melting, we could see “a very sudden, big burst of warming that would be disastrous,” he says. But Francis says that offshore permafrost is much less of a concern right now since the ocean waters deep down are still very cold. “We got other things that are much bigger to worry about right now,” she says.

What’s next?

Since the 1980s, the area covered by Arctic sea ice in the summer has shrunk by about 40 percent, according to NASA. The ice is also becoming thinner. It’s really hard to predict when we could see ice-free summers in the Arctic, but it could be as soon as in 20 to 40 years, Francis says. (In the winter, the North Pole has six months of darkness, so it’s likely that the ice will stay during that time of the year for a long time.) It all depends on how warm our planet gets — and to limit that, we need to reduce the amount of greenhouse gases that enter the atmosphere.

The likely solution, according to Wadhams, is the development of “carbon capture” technology that can remove CO2 from the air. Some projects are doing this already, but they’re not large scale enough to really make a difference. But if we devote enough research dollars to the problem, Wadhams is confident that we will find a solution. Francis agrees: once emitted, CO2 stays in the air for 100 to 200 years, so “all of the emissions that have occurred are going to affect us for a long time, unless we can figure out a way to remove them from the atmosphere.”

Wadhams adds: “In the end, that’s the only thing that will save us from global warming.”



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