Simultaneously, a team of glaciologists camped on a ridge overlooking the glacier. and mighty, filling valleys of their own making. A new way of measuring how some glaciers melt below the surface of the water has uncovered a surprising realization: Some glaciers are melting a hundred times faster than scientists thought they were. As it retreats, it will steadily add to the fresh water Alaskan glaciers are spilling into the ocean. Students at Petersburg High School near LeConte Bay started collecting data about the position of the glacier’s terminus in 1983. Sutherland, an oceanographer at the University of Oregon, explained that his techniques are likely to apply worldwide. Usually less than 6 degrees Celsius, water in LeConte Bay is warm relative to the ice, and even other fjords around the world. The ice was certainly receding, but the glaciers were still sprawling In October, researchers announced that Alaska’s massive Taku Glacier has started retreating. From the 80-foot MV Stellar, oceanographers performed sonar surveys underwater, like the ones used to measure ocean depths. Primarily a massive ice sheet, Greenland has about 200 outlet glaciers, but the water there is much colder compared to the temperature in LeConte Bay. Their noting of the glacier’s retreat several years ago alerted scientists at the University of Alaska Southeast, piquing interest in better understanding melting at the glacier. It's Worse Than Previously Thought An iceberg from the LeConte Glacier drifting in LeConte Bay, Tongass National Forest in Alaska. Magazine. Alaska's temperature has risen by four degrees Fahrenheit in the last 50 years, that's compared with two degrees for rest of the planet, leading to melting glaciers. Today, scientists are attempting to put hard numbers the amount of meltwater flowing from Alaska’s glaciers. And then you have this submarine melting that occurs wherever the ocean touches the surface of the glacier. public. ANCHORAGE, Alaska Melting glaciers are not just impacting sea level, they are also affecting the flow of organic carbon to the world’s oceans, according to new research that provides the first ever global-scale estimates for the storage and release of organic carbon from glaciers. Lance King/Getty Images Sometimes that meant the boat suddenly had to retreat from the face of the glacier, while scientists crossed their fingers that the equipment wasn’t sheared off into the water. For nearly 30 years, I have lived and worked alongside Alaska’s melting glaciers. Finding higher rates of submarine melting tells us that “glaciers are a lot more sensitive to ocean change than we’ve even thought.” Understanding the melting processes and calculating the amount of melt accurately is essential for planning for sea level rise. Most glaciers in Alaska are temperate, meaning they are at their melting point from surface to base and contain large pockets of water within the ice that scatter radar waves. To further complicate things, the tall mountains encasing the narrow glacier valleys reflect radar waves as frequently as the bedrock does. Another study of the world’s mountain glaciers predicts that at the current levels of fossil fuel use their melting in the decades ahead will spill enough freshwater to raise seas by up to 10 inches. YES! It is expected to contribute to famine, conflict, and other human migration crises in our lifetime. A view of Denali National Park, Alaska, on September 1, 2015. At visitor centers, they can watch the change unfold on time-lapse videos. Fortunately, scientists have some time to figure it out. Three studies published this year underscore not just the rapid loss of the globe’s glacial ice, but the rate of the melt and its contribution to sea level rise. With a glacier, you have to know how fast the ice moves into the fjord, as well as what proportion is melting and what proportion is breaking off, or calving. “We’ll have to see if the Forest Service implements them.”, Moon, the researcher, also believes in the importance of educating the public about melting glaciers. The glaciers are situated on 11 mountain ranges, 1 large island, an island chain, and 1 archipelago and range in elevation from more than 6,000 m to below sea level. Melting has left these slow-moving rivers of ice, while still Among the most worrisome of all climate change impacts, rising seas threaten to displace millions of people from coastlines across the globe. Glaciers are large sheets of snow and ice that are found on land all year long. heat—including 90-degree temperatures Why are there glaciers? Over time, great glaciers where I had camped and worked slumped downward. Glaciers Are Melting Underwater. In this light, Alaska’s glaciers stop being mere wonders of the world, “Submarine melting may matter everywhere,” says Enderlin. The study also found that melt rates are higher in the summer than in the spring and that changes in the melting rate can lead to undercutting and uppercutting eating away at the glaciers. WCCO Sunday Morning – Oct. 29, 2017 warming.”. Europe. The studies attempt to put tangible numbers on just how much Alaska’s melting glaciers affect global sea levels. Before this summer, it was the last major glacier in the Juneau area to remain stable in the modern era. GLACIERS OF ALASKA. Things have gotten bad enough that glaciers are practically on the edge of extinction. Rignot said one of the theoretical models, used for 20-30 years, was known to be a simplified version that didn’t work perfectly. It is the easiest glacier to visit in Southeast Alaska, and one of the most popular glaciers in the state. As glaciers shrink, the melting is disrupting habitats for everything from bacteria to fish. “A pretty large percentage of the ice that flows into the ocean is melted away by the warm ocean water,” says Amundson. This stunning short film examines the glacier’s dramatic impact through the voice of local guide Rick Brown. Carbon dioxide emissions are one big culprit. “These glaciers aren’t getting lost that fast…they’ll be around for decades to come,” says Sutherland. Several processes of melting happen at a tidewater glacier, which is why scientists tackled the melting mystery from multiple angles. Oceanographers then had to know how quickly the sonar traveled through the fjord water to make accurate calculations. In Seward, Alaska, Exit Glacier is melting at an astonishing rate. And it is forcing us to think differently about Warmer temperatures cause glaciers to melt faster than they can accumulate new snow. © 1996-2015 National Geographic Society, © 2015- The Wolverine Glacier on the Kenai Peninsula south of … “Alaska’s glaciers are in kind of a Goldilocks position,” says Twila He recalls trying to give visitors “somewhere to take that sense of loss.”, “During my time at the glacier, I tried to plant the seeds of hope by planning for changes in facilities and infrastructure that embraced sustainable energy principles,” he said. Alaska's heat wave is driving wildfires and melting glaciers, choking the state’s biggest cities with smoke and bloating rivers with meltwater. An unprecedented ‘mega-tsunami’ could be caused by a melting Alaska glacier, scientists have warned. 284 Madrona Way NE, Ste 116, Bainbridge Island, WA 98110, Custom Service Can Be Reached at 800-937-4451, +1-206-842-0216, or by Mail At. “A considerable amount of ice that gets pushed out into the ocean melts right there where it’s in contact with the ocean…so that glacier is actually losing a lot of mass due to that melting,” says Enderlin. “To be able to scan an entire glacier face repeatedly over the summer is not easy,” says Eric Rignot, a glaciologist at the University of California, Irvine who was not involved with the study. They calculated that the glacier melted underwater at a rate of almost 5 feet per day in May and up to 16 feet per day in August. Only 50 of approximately 100,000 glaciers in Alaska are tidewater glaciers, and they’re some of the biggest. underestimating the speed of their melting. Moon, a research scientist with the National Snow and Ice Data Center at the They developed holes and fissures that never healed but only expanded until entire limbs of ice disappeared. Among the most worrisome of all climate change impacts, rising seas threaten to displace millions of people from coastlines across the globe. Photo by Wolfgang Kaehler/LightRocket/Getty Images. Glacial ice accelerates as the ice approaches the front of the glacier, where it drops into the ocean, said Moon. All Rights Reserved. The more buoyant freshwater rises to the surface and then undercuts, or erodes the glacier face. human-caused climate change,” says John Neary, the visitor center’s former spectacular, much diminished. Here’s what to see now, and how. During his tenure, Neary ushered in a new era If you turn the knob of climate up, like with climate change, says Sutherland, you increase the temperature of water and air and you will certainly get more melting. “Our study calls for a reconsideration of melt rates calculated by theory,” lead researcher David Sutherland wrote in an email. When a plume of freshwater from surface melt enters the fjord, it hits the fjord close to the glacier face. The center’s 500,000 summertime visitors find The tributary located high above Pedersen Glacier separated from it … Specifically, insight from the research at LeConte Glacier in Alaska could be used to study glaciers in Greenland and Antarctica. “So much depends on our actions today.”. them. Hence their melting must raise a concern. On Mont Blanc, the highest peak in the Alps, the Argentière Glacier has receded 1,150 m (3,770 ft) since 1870. Alaskan glaciers published in 2019 suggests scientists may still be Alaskan glaciers primarily experience surface melt, since so few end in the ocean, said Rignot. Glaciers in Greenland and Antarctica are losing ice at alarming rates, and warmer air isn’t the only cause. Melting glaciers increasing risk of landslide-triggered tsunamis, study reveals. In April 2019, an international research team estimated the world’s mountain glaciers, which do not include the massive ice sheets of Greenland and Antarctica, lost a hard-to-fathom 9,000 billion tons of ice over the past 50 years. Abstract. New studies put hard numbers to Alaska's glacial retreat, now plainly visible to tourists. Every year, seemingly incalculable torrents of meltwater poured into the sea. Specifically, since the industrial revolution, carbon dioxide and other greenhouse gas emissions have raised temperatures, even higher in the poles, and as a result, glaciers are rapidly melting, calving off into the sea and retreating on land. The most hike-able glaciers in Alaska are undoubtedly going away. Glaciers are found in the western United States, Alaska, the mountains of Europe and Asia, and many other parts of the world. Even though these mountain glaciers comprise only 4 percent of the world’s land ice, their melting has so far fueled up to 30 percent of global sea-level rise, the research shows. but they’re also at that southern Arctic edge where we see so much change from It was “pretty simple in my head, and sounded good on paper,” laughs Sutherland. A new study shows that its glaciers are melting faster each summer. One of the world's thickest mountain glaciers is melting because of global warming. By. Scientists spent weeks aboard the boat working 24 hours a day, with each scientist taking 12-hour shifts. More than mere sources of beauty, they now represent a collapsing Alaska’s Muir Glacier, like many Alaskan glaciers, has retreated and thinned dramatically since the 19th century. Sign up to receive email updates from YES! What's happening now? All the while, meltwater tumbles past in swift, cold rivers – destined for the ocean. Researchers pegged Alaska as the largest single contributor to the melting. Wendy Gillette reports on the warming climate in Alaska and the melting of that state’s many glaciers (2:12). but it was peripheral to the experience and seemingly too far-off for alarm. landscape. has worked on public lands issues for many years and is a founding member of the Prince William Sound Stewardship Foundation. It could affect predictions for sea level rise. Greenland experiences surface melt as well as melting by tidewater glaciers. Back at the Mendenhall Glacier Visitor Center in Juneau, the U.S. as it can help people understand and perhaps act upon the growing climate emergency. But a warming climate accelerates glacier melting across the globe, potentially through melting across the surface of the glacier, but also through underwater melting. pushed rivers toward flood stage. Climate change was discussed, Ice near the glacier face can move almost 75 feet per day and knowing this speed is essential to calculate melting. showcased on tourism brochures, but instead are now seen as a vital part of the 2020 National Geographic Partners, LLC. She compares the ice movement to squeezing a tube of toothpaste: Once your toothpaste gets to the very end, it doesn’t have any other toothpaste blocking its progress, so it moves more quickly. I say this as someone who has witnessed the change up close. This particular pair of images shows the glacier’s continued retreat and thinning in the second half of the 20th century. Yakutat, near the Alaska town of the same name, is a withering glacier that calves into a deep lake of its own making. As it dies, Yakutat Glacier will increase the number of glaciers in Alaska. Copyright 2019 YES! “The proximity of Alaska’s glaciers to the ocean puts them in an especially sensitive area,” Moon says. Scientists repeated their observations during two summers, obtaining multiple scans each trip. Tidewater glaciers, like this one in Alaska, experience underwater melting 100 times faster than scientists previously estimated from theoretical models. The melting caused rivers to flow out of their banks and all that meltwater poured into the ocean. of more open dialogue about climate change at the Mendenhall. His writing has appeared in Hakai Magazine, The Revelator, The Hill, Terrain.org, and elsewhere. Mountain goats scrambled on ridges above and whales frequented the fjord, with seabirds dipping into the water. That can be difficult to disentangle from natural melting, though. One of the USA's tallest glaciers is melting at the fastest pace in 400 years, a new study reports. 2. of Alaska, about 5 percent of the State. “As more precipitation falls as rain throughout the year [in coastal Alaska], they’ll continue to be an important player in sea level rise.”, “Visitors are taught that the glacier is disappearing because of human-caused climate change.”. Today’s visitors to Alaska find a landscape transformed, with raw mountainsides only recently stripped of their ice. In this research, too, Alaska’s glaciers emerged as the top source of meltwater, with up to half of their mass expected to melt in the coming years. If you want to explore them before they’re gone for good, don’t wait too long. including underwater sonar surveys of the ice, researchers discovered melt While pioneering new techniques, A visitor center operated by the U.S. Forest Service is open year-round with spectacular views and interactive exhibits, plus you’ll find great hiking to waterfalls and overlooks for photography. The Taku Glacier, located north of Juneau, Alaska, has started to retreat as temperatures rise. But the planet’s warming became a much more immediate concern for me in the ensuing years, as I watched the ice calve away. The extremely well-preserved frozen bodies of … But a warming climate accelerates glacier melting across the globe, potentially through melting across the surface of the glacier, but also through underwater melting. In April 2019, an international research team estimated the world’s mountain glaciers, which do not include the massive ice sheets of Greenland and Antarctica, lost a hard-to-fathom 9,000 billion tons of ice over the past 50 years. Burning Questions about Glacial Ice. University of Colorado Boulder, who did not participate in the study. They “babysat” a delicate radar instrument to measure the natural movement of the glacier. Monitoring specific glaciers for a long period of time can give researchers—and high school students—an idea of climate change-induced melting. Calculating how fast a glacier melts requires more finesse than measuring a melting ice cube in a glass of water. “We weren’t 100 percent sure it was going to work.”. Melting Glaciers. The story of Alaska’s glacial retreat is plainly written across the As the summer sun beat down, more meltwater flowed beneath the glacier and into the ocean, pushing the relatively warm seawater against the submerged face of the glacier and melting it. Publishes Quarterly in February, May, August, and November. connect people to the seriousness of climate change. But in Antarctica this submarine melting is the only type of ice melt, so understanding the processes outside Alaska are important. I began as a young Forest Service naturalist at the Mendenhall Glacier Visitor Center in Juneau, where my first experience with glaciers was all about wonder and adventure. in a region where 60s and 70s are more the norm—sparked severe melting that Some of this calving and glacial melt is a normal process that glaciers undergo during seasonal transitions from winter to summer, and even through the summer. naturalists trained to navigate the challenges of discussing the topic with the Scientists are racing to understand the changes. “Visitors are taught that the glacier is disappearing because of 1. But navigating a boat into the fjord, where the LeConte Glacier slips into the sea, is tricky on a good day. “When you aren’t wishing for better weather…it was a pretty awesome place to be,” says Sutherland. Time-lapse cameras were used to measure glacier flow so that they knew how fast the ice moves toward the ocean, says Jason Amundson, a glaciologist and co-author of the study at University of Alaska Southeast. In France all six of the major glaciers are in retreat. INCAN CHILD SACRIFICE VICTIMS // ARGENTINA. prominent displays linking the glacier’s retreat to climate change and rates more than 100 times greater than those predicted by models. “I’m hopeful that it can make people understand that the future of ice is not set in stone,” she says. Too much ice in front of the glacier means “the boat can’t push through the ice,” says Rignot. “They are The success of the new method “opens the door for researchers to do this all over the world,” says Sutherland. All rights reserved. Glaciers cover about 75,000 km. The studies attempt to put tangible numbers on just how much Alaska’s melting glaciers affect global sea levels. Further “basic” measurements of water properties, like salinity and temperature, were necessary, Sutherland explained. LeConte was an ideal glacier to study because it is really accessible for a tidewater glacier, Sutherland said. From the datasets, researchers were able to calculate a total melting rate for the underwater portion of the glacier: two orders of magnitude higher than they expected. These “glaciers can change much more quickly than valley glaciers because of the processes that are happening right where the glacier flows into the ocean,” says Amundson. “People are stunned when they view our time-lapse video of the shrinking Mendenhall,” Neary says. Chunks of ice calving from South Sawyer Glacier in Tracy Arm, a fjord in Tongass National Forest near Juneau, Alaska. Other Mont Blanc glaciers have also been in retreat, including the Mer de Glace, which is the largest glacier in France at 12 km (7.5 mi) in length but retreated 500 m (1,600 ft) between 1994 and 2008. That was never truer than this past summer, when record-setting That amount alone is enough to inundate vulnerable coastal population centers from Florida to Bangladesh. “We are just super jazzed that we can even do this,” says lead author David Sutherland, an oceanographer at the University of Oregon. The concerned experts claim the catastrophic event could even … Pedersen Glacier's terminus has retreated more than 2 kilometers (1.24 miles). Glaciers form where more snow falls than melts over a period of years, compacts into ice, and becomes thick enough to begin to move.That is, a snow patch becomes a glacier when the deepest layers begin to deform due to the weight of the overlying snow and ice. “It’s a real call to action,” to better understand how these systems work. Meanwhile, a third study of Sliding glaciers ‘a new threat’ as global warming melts ice. Alaskan glaciers melting 100 times faster than previously thought, https://www.nationalgeographic.com/environment/2019/07/alaskan-glaciers-melting-faster-than-previously-thought.html, collecting data about the position of the glacier’s terminus, Alaskan glaciers primarily experience surface melt. The rising temperature of the Earth is the primary reason glaciers have started to melt more, and this climate change can be directly tied back to human activity. The opportunities for—and the importance of—such education is only growing. Glaciers are popular destinations for tourists, but access to them is changing fast as they recede. Instead of directing the sonar toward the ocean floor, though, they angled the sonar to collect the 3D underwater portion of the glacier face. Forest Service is demonstrating how melting glaciers provide an opportunity to Alaska’s glaciers extend geographically “These observations pretty clearly show us that there are things that we’ve been missing,” says Moon. If a big block of ice is sitting in a bathtub and nothing else is going on, it would just be melting at a background rate. In a new study published today in Science, a team of oceanographers and glaciologists unpeeled a new layer of understanding of tidewater glaciers—glaciers that end in the ocean—and their dynamic processes. The really cool part of the new method, said Sutherland, is that you can pinpoint the exact location where higher melt occurs. Later in the season, the warmer water increased the underwater melting. They're found in the western United States, Alaska, the mountains of Europe and Asia, and many other parts of the world. system that for millennia has helped cool the globe and kept sea levels stable. A complex environment, the project required so many lines of data that teams of oceanographers and glaciologists collected data simultaneously at the glacier. director, who recently retired. This more systemic outlook on glaciers is important to adopt, say some experts, Dangling super-expensive instruments over the side of the boat could sometimes be tense. BRUCE F. MOLNIA. planet’s cooling system being critically damaged by burning fossil fuels. It is expected to contribute to famine, conflict, and other human migration crises in our lifetime. Glaciers can extend hundreds of feet below the surface, explained Ellyn Enderlin, a glaciologist at Boise State University who was not involved with the study. far enough north that they get the snow necessary to form very large glaciers, “They’ve really discovered that the melt that’s happening is fairly dramatically different from some of the assumptions we’ve had,” says Twila Moon, a glaciologist at the National Snow and Ice Data Center at the University of Colorado-Boulder who was uninvolved with the study.