Greenland’s Jakobshavn Glacier Reacts to Changing Ocean Temperatures

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Generally speaking, as the climate warms, ice around the planet melts. But how fast it melts and where it melts is complicated by factors like how the climate’s changing and local weather patterns. Here at NASA, we use satellites, airplanes and research ships to take a closer look at the regional causes of melting and what’s driving them. NASA’s mission Ocean Melting Greenland, or OMG for short, is designed to figure out how much of Greenland’s ice loss is being caused by the oceans. Sometimes the oceans affected Greenland’s ice in surprising ways. This year, we figured out for the first time in almost 20 years, Greenland’s biggest glacier, Jakobshavn, stopped retreating and got thicker. The big question: Why? After looking at dozens of potential causes, we figured out that Jakobshavn’s slowdown was caused by cold water that flowed in from offshore. Where Jakboshavn meets the ocean, it sits in water that’s almost 2,400 feet deep — that’s like eight football fields — and this water can affect the glacier very far inland. Water in Disko Bay, shown here, flows into the canyon, or fjord that holds Jakobshavn, sometimes the water is warm, speeding up the melt of the glacier, and sometimes, it slows it down. In 2016, the water in Disko Bay got cold, reaching temperatures that were lower than at any time since the late 1980s. Natural cycles cool and then warm the far north Atlantic Ocean about once every 20 years. This cold water from 2016 arrived just as the Atlantic was shifting to its next cold period. Watch as the deep water temperatures warm up slowly through the years, until 2016, then get cold again. These waters are brought into Disko Bay by the currents of the North Atlantic, which flow around the southern tip of Greenland, carrying water northward up its west coast. The cold water in Disko Bay caused a dramatic change in Jakobshavn, making it grow taller by 100 feet, or 30 meters, between 2016 and 2017. What does this mean for Greenland? It means that the oceans play a key role in Greenland’s melt, and we have to watch the water just as closely as the ice if we want to know what the future holds. Here at NASA, we’re hard at work in the field, and the lab, to better understand how the ocean affects Greenland’s melting and how that will continue to change with the climate. NASA

29 COMMENTS

  1. NASA ‘s numbers don’t add up , 100 ft of ice in one year when it does not even snow that much over one year . Get your facts straight.

  2. For those wondering about Antarctica while watching this, the Jakobshavn is the most common type of glaciers around Antarctica because it is mostly affected by warm water unlike most of Greenland's glaciers.
    A study was made by prominent glaciologist Richard Alley who applied the Jakobshavn model to Antarctica and cut ice mass loss by 50% to be on the conservative side of estimates. The end result was a total of 7 and some meters of sea level rise by 2100, which was of course played down by other scientists.
    Not claiming he's right or wrong and I won't be around by 2100 to verify his claim (and that of his team). Just making this nerdy point.

  3. Wow that's so cool and interesting that's alot of water and ice to come yet more changes to come sooner than anyone really knows i think

  4. We're supposed to believe at 1:35 that the "Deep water warms up". In my world warm water rises to the top. This whole You Tube sounds like the "Dog ate my homework" excuse.

  5. So the guy who sold me wind power said that all 'climate change' was manmade. I think I'm paying too much for fracked gas- because of the guilt tax added on by the propaganda machine. Pollution is a better term to use for overproduction of manmade chemicals (carbon dioxide being one of those chemicals).

  6. "They traced the causes of this thickening to a temporary cooling of ocean temperatures in the region" TEMPORARY? What? What evidence draws this leap to conclude that this is merely temporary? Great, you just slapped Michael Mann in the face with an open hand and got his frothing spittle all over Al Gore's new Canada Goose Parka, while jack-knifing the whole Global Warming train in the middle of a hundred year record Nebraska cold snap and snow storm? What next? The Sun is cooling? I won't accuse you of science, yet but you are dangerously close to performing science.

  7. Just check other reporting and compare NASA climatesplaining. Always "the gods are angry and only we can appease them, you must do as we say" the only facts are that carbon dioxide has increased from 0.03% to 0.04% of the atmosphere over the past 150 years and that global average temperature has increased 0.8°C everything else is probabilities and statistics with heavy confirmation bias (so heavy that dissenters are expelled from the team unless they wholly endorse climate eschatology)

  8. The north see warmt and cold records every winter and summer! Its getting hoter and its getting colder, and that means only 1 thing : there is more energy being transformed too the weather every year! Stronger storms – more storms – more rainsnow! 2 outcomes; storms take over the planet, looking out the sun – new iceage! Or the core temp on Earth is so fragile that if the system around get 2-4 degrees hoter the earth gets a fever and vulcanos will fire everywere!

  9. No, the ocean temperature hasn't changed nor would we expect a loosely estimsted 0.01 degree average yearly change in surface temperature to change it. The ocean is quite massive

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