Later On

A blog written for those whose interests more or less match mine.

Greenland’s effects on South Carolina flooding

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The above video, of the largest calving event caught as it happened, was linked in a report in the Post and Courier in Charleston SC. The paper sent a reporter, Tony Barleme, to Greenland to take a look at the effects of global warming, which is affecting South Carolina (and Charleston is right on the coast). He reports:

1. Gravity

So many things in Greenland are gigantic. Greenland is five times the size of California, and roughly 80 percent is covered with ice. Greenland’s ice sheet is a mile deep on average, but near the center of the country it rises 10,000 feet into the sky. Greenland’s ice sheet is so thick and heavy that it makes the Earth wobble a bit as it spins, like an unbalanced top. When the ice sheet meets the ocean, the ice sometimes cracks and falls with the force of atomic bombs. Even Greenland’s language, Greenlandic, has huge words — one is 153 letters long.

Greenland’s ice is melting in a big way, too. This summer, so much melted in one week that you could flood the entire state of South Carolina with 2 feet of water. The ice sheet normally melts in the summer, but it’s melting faster now than it has in 12,000 years.

All this melting ice raised sea levels across the globe, just as dropping ice cubes into a whisky drink eventually makes a mess. Except some ice cubes in Greenland can be half the size of Manhattan.

There’s more: The Greenland ice sheet is so massive that it generates its own gravity. It pulls the Atlantic Ocean toward it like someone tugging a blanket. South Carolina is at the other end of this blanket, which means that Greenland pulls water away from our coast, lowering our sea level. But as the ice melts, its gravity disperses and its grip loosens. Seas at the far end of the ice’s power slosh back.

That’s one reason sea levels in South Carolina have risen faster than many other places around the globe.

Greenland is 3,000 miles north of Charleston, but this distant land of ice, polar bears and reindeer already has reshaped our coastline. It has made Charleston’s tides higher, our flooding worse. And what happens in Greenland in the future will largely determine the Lowcountry’s fate.

These forces come with overwhelming numbers, so it’s best to start smaller. Perhaps by flying in a 78-year-old plane over the world’s fastest-moving glacier.

With an Elvis impersonator on board.

2. The ice has left the building

It was the middle of August, and the afternoon temperature was in the low 60s, speeding up the summer melt. Above western Greenland, Josh Willis crouched in the back of a World War II-era DC-3.

He wore a blue NASA jumpsuit and cradled a 3-foot-long metal tube. He peeled off a sticker that said “REMOVE BEFORE LAUNCHING.” Setting the tube down, he opened a round metal hatch in the floor. Through the hole, you could see the Ilulissat Icefjord below.

Willis has a cherubic face and those long Elvis sideburns. Mention that he looks like Elvis and he lowers his voice and answers with the King’s trademark, “Thank you very much.” He’s a graduate of Second City’s comedy school in Los Angeles and has done shows on Hollywood Boulevard. His performances are a bit of oil and water — climate science and comedy. But he thinks that scientists could do a better job talking about their discoveries, and humor helps. For a science communication contest a few years ago, he and friends did a music video called the Climate Rock. In it, an 11-year-old asks, “What is climate?” Willis, in a 1970s Elvis jumpsuit, sings:

“You take a bunch of weather and you average it together and you’re doing the Climate Rock!”

Climate Elvis was born.

Willis has a more serious day job: climate scientist with NASA’s Jet Propulsion Laboratory in Pasadena, Calif. He leads the agency’s OMG project, which does not stand for “Oh My God,” though Willis does find himself saying that when he looks below and sees Greenland’s cathedrals of ice. It stands for Oceans Melting Greenland, a title he cooked up a decade ago as a catchy way to describe the project’s central question: Do warming oceans affect Greenland’s ice sheet?

Which is how he ended up throwing things out of airplanes.

•••

The Ilulissat Glacier is a key OMG target and one the most important glaciers you’ve probably never heard of. It pours into a large valley near the town of Ilulissat, which is pronounced illoo-lih-sat and means “icebergs” in Greenlandic. The glacier also goes by other names: Jakobshavn, after a Danish merchant, and still used by many scientists; and the Greenlandic name “Sermeq Kujalleq,” or south glacier. But given all the giant icebergs, Ilulissat fits best.

About 40 miles from the sea, the Ilulissat Glacier forms an 8-mile wall called a calving front. Here, ice moves toward the ocean at 150 feet per day — a pace that tripled during the 1990s and 2000s. As it moves, it creates a great white shelf over the water that breaks off, often violently.

On warm days, the ice cracks like cubes after they’ve been dropped in a warm drink, except these cracks sound like thunderclaps and shake your ribs. Chunks as large as skyscrapers crash into the water, launching ice shards and spray. Some fractures release so much energy that geologists call them glacial quakes. Earthquake instruments across the world detect the biggest calving events. In 2008, a crew for the documentary “Chasing Ice” watched part of the ice wall collapse in a roar of thunder and white. The chunk was larger than 3,000 Egyptian pyramids.

All this falling ice flows down a fjord that’s 2,500 feet deep. But near the fjord’s mouth, the biggest icebergs hit an underwater speed bump — a sudden rise in the seabed that’s still about 800 feet deep. This bump creates the world’s most beautiful traffic jam.

Icebergs with giant arches crowd ones that look like snow cones, alligator heads and cowboy hats. Blue meltwater rivers speed down shimmering white slopes. Humpback whales swim between iceberg cliffs. Water streams off the cliffs, sounding like a steady rain. Some icebergs lose their balance as they melt. Without warning, they do summersaults, even ones as large as aircraft carriers. This can swamp fishing boats and smear the water with white ice bits for miles.

Over time, ice melts below the big icebergs, enough to clear that 800-foot-deep speed bump. Freed from the fjord, they float into the open ocean, propelled now by powerful currents.

But this traffic jam had long given OMG fits. The NASA crew needed space in the water to drop their probes, and sometimes the bergs were bumper to bumper. A few days before, they’d found an opening to drop a probe. But it didn’t broadcast any data. Now they were back for another try.

And Willis badly wanted the measurements, in part because of what they’d discovered a few years before. . . 

Continue reading. There’s much more.

Written by Leisureguy

28 September 2021 at 12:46 pm

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