The South Pole's ice is in danger of melting away before our eyes

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1 The South Pole's ice is in danger of melting away before our eyes By Los Angeles Times, adapted by Newsela staff on Word Count 752 This undated handout photo provided by NASA shows the Thwaites Glacier in West Antarctica. Two new studies indicate that part of the huge West Antarctic ice sheet is starting a slow collapse in an unstoppable way. Alarmed scientists say that means even more rises in sea level than they figured. Photo: AP Photo/ NASA A huge group of glaciers in Antarctica is melting, according to two studies. The melting glaciers mean that sea levels could rise another 4 feet within 200 years. But if global warming slows down, a complete melt may be delayed. That might give scientists time to figure out how to lower the side-effects of rising sea levels. Researchers had thought that the cluster in the Amundsen Sea region of the West Antarctic Ice Sheet would last for thousands of years. But new studies found that glacier collapse is underway. And it's happening more quickly than scientists expected, according to the studies released Monday.

2 The warming water has several causes. This includes global warming ( warming) from burning fossil fuels like coal, oil and gas and lower ozone levels. Ozone is a gas in the atmosphere that blocks some of the sun's heat. The lower ozone levels have changed wind patterns over the water. Too Late To Go Back There is no red button to stop this, said Eric Rignot. He is a University of California, Irvine glacier expert and wrote one of the studies. The glaciers have passed the point of no return, Rignot said. That means the melting of the glaciers cannot be prevented. The only question is how fast it s going to go. Antarctica, which surrounds the South Pole, has the largest amount of ice on the planet. It contains an estimated 80 percent of the world s fresh water. Here is one way to imagine how much ice that is. If you loaded all its ice onto ships and started counting them, one per second, it would take 860 years before you finished. The loss of even some of that ice would be felt across the globe. For one of the studies, scientists used 40 years worth of measurements. Much of it came from satellites that measure changes on Earth s surface. The information was used to measure the exact location of the glaciers grounding lines. The grounding line is where glaciers connect to the ocean bottom. It is here that warming ocean water begins to cause the glaciers to melt. From there the problems multiply, scientists said. Warmer Water Is Deadly The more they melt, the less glaciers weigh. This lifts them farther off the bottom of the ocean. That allows even more warm water to melt them. And as the glaciers float into deeper parts of the ocean, they become more exposed to warm water. In the second study, researchers at the University of Washington focused largely on the Thwaites Glacier. They were trying to figure how quickly the giant Thwaites might disappear altogether. The disappearance of the Thwaites could cause sea levels to rise 2 feet. And that would be a disaster. Even if the sea level rises less than 2 feet, it would threaten parts of the Pacific Coast Highway in California. It would flood power plants and water treatment plants. It would also cause big rain storms.

3 The Washington study determined that the Thwaites could melt in as little as 200 years or as long as 1,000 years. Ian Joughin studies glaciers. He is also the lead author of that study. He said the 200-year estimate is more likely. He said the glacier's disappearance would begin slowly and grow faster over time. Still Time To Slow It Down The Thwaites is an important test case. As goes the Thwaites, many scientists fear, so goes the rest of the ice sheet. If the Thwaites disappears, many more miles of glaciers would come in contact with the warming ocean water. You can t just remove this glacier cleanly, Joughin said. You pull one part out, the rest will move into" its place. If the entire ice sheet disappeared, the sea level around the planet could rise 15 feet. Eventually, this could lead to the (end) of ice across Antarctica, Rignot said. There's no stopping the glaciers from melting. But people shouldn't just surrender. The more global warming, the more glaciers will melt. But the reverse is true, too. Eight hundred years is a long time, Joughin said. Less global warming means less melting. If global warming is really slowed or stopped, they could take closer to 1,000 years to melt. Think of the technology that has been invented in the last 800 years, Joughin said. And think of the technology that can be invented in the next 800 years. The system really is going down, Rignot said. How fast it is going to go is critical.

4 Quiz 1 Why is the Thwaites considered an important test case by scientists? It is the largest glacier. It is the fastest melting glacier. Its melting will speed up the melting of other glaciers. Its melting will cause the sea level to rise by up to 15 feet. 2 Which of the following is NOT a reason for an increase in global warming? burning of oil burning of coal depleting ozone layer changes in grounding lines 3 Select the paragraph from "Too Late To Go Back" that describes the source of information on which one of the studies is based. 4 Which of the following does the article draw a connection between? 860 years and the Thwaites Glacier Antarctica and lower ozone levels grounding lines and melting of glaciers water treatment plants and warm water

5 Answer Key 1 Why is the Thwaites considered an important test case by scientists? It is the largest glacier. It is the fastest melting glacier. Its melting will speed up the melting of other glaciers. Its melting will cause the sea level to rise by up to 15 feet. 2 Which of the following is NOT a reason for an increase in global warming? burning of oil burning of coal depleting ozone layer changes in grounding lines 3 Select the paragraph from "Too Late To Go Back" that describes the source of information on which one of the studies is based. Paragraph 8: For one of the studies, scientists used 40 years worth of measurements. Much of it came from satellites that measure changes on Earth s surface. 4 Which of the following does the article draw a connection between? 860 years and the Thwaites Glacier Antarctica and lower ozone levels grounding lines and melting of glaciers water treatment plants and warm water