Greenland Melting (360°)

[Music] [Music] [Music] the island of Greenland is covered with an enormous ice sheet in some places two miles thick if it all melted it's estimated that the sea level around the world would rise by about 20 feet for centuries the ice year was relatively stable but recently it's been melting faster and faster [Music] nasa scientists are trying to find out exactly how fast the glaciers of Greenland are melting and moving water into the sea leading the team is Josh Willis this is a dangerous place to be this is West Greenland 220 miles north of the Arctic Circle and we're looking at the Averna lick clay sure it's a river of ice made up of snow compacted over thousands of years and it empties right here into the ocean at any moment a huge chunk of ice could break off and crush a person if they were standing right here or cause a tidal wave that would sweep a person away but this ice isn't just dangerous because it's falling the glacial flow of a Verna lick is speeding up just like glaciers all across the world 15 years ago this glacier was losing ice at a speed of about 3 feet per day according to scientists latest measurements it has tripled its speed now losing 10 feet per day and it's not the only one that is melting faster you were on the deck of a nasa research boat called the Neptune this is the Bernstorff you are Eric green yo is a professor at UC Irvine and a senior scientist on the NASA team in the distance about 3 miles from here a simple relation fable glacier didn't used to be that far it used to be much much closer in fact about 100 years ago it was right here the glacier retreated more in the last 15 years than in the previous 70 years we'd like to know why this is what we came here we think climate warming has something to do with it and not just air temperature because air temperature is not enough to explain this between we think something is happening down below in the ocean we're downstairs inside the boat the computers behind me are connected to a sonar that's scanning the shape and depth of the seafloor that's important because the glaciers are sitting right in the water and water is really good at melting the ice just imagine an ice cube melting in a glass of water as opposed to an ice cube left out on the counter in the air the water is really good at melting ice because it contains so much heat and the warmer the water the faster it melts so to better understand how fast Greenland's glaciers will melt and raise sea level scientists need to figure out how much of that ice is sitting underwater and how warm that water is the NASA team is trying to measure this from the Neptune but also from the air this is NASA to the Gulfstream 3 that is my home for about five weeks a year when we're in Greenland taking measurements it's probably the most important platform we have for our mission because it allows us to get to every corner of Greenland in just a few weeks the racks here communicate with the radar that we attach to the bottom of the plane the radar measures the ice height and tells us which glaciers are shrinking and retreating the fastest we also drop probes through a tube in the back of the plane this is where we drop the probes through this tube that fall to the seafloor and measure temperature and salinity so when we get to the right spot the pilot says 3 2 1 drop pretty soon its radioing data back from the surface all the way to the seafloor something we've never been able to do before this is what the Kangol are not a glacier in West Greenland looks like from the air it's about two and a half miles wide on both sides of the fjord you can see a line of lighter colored rocks where ice used to be in the last 15 years more than five square miles of this glacier have been lost to the sea parts of the glacier tower a hundred and sixty feet above the ocean but how much of this ice is sitting in the water the data gathered by NASA provides a clearer picture try looking below the water's surface it turns out that this fjord is around a thousand feet deep meaning that most of the glacier is underwater and here the deeper water is warmer the NASA research shows that warm salty currents from the Atlantic are eating away at the glacier from below now this appears to be happening to glaciers all around Greenland scientists like Josh and Eric think this could be one big reason why the ice here is breaking up and melting faster and faster [Music] when you look at the glacier like that vantage point of America after it looks like it's going to be here forever how could it possibly go away out the window of this helicopter is the largest glacier in Greenland Jakob Savin the glacier here is about 12 miles long Jakub sovereign is world-famous because it produces some of the biggest icebergs and it is believed that the one that sank the Titanic might have come from this glacier in the last 15 years Jakob Holland has lost more ice than it did in the previous century shedding 10 miles worth of ice into the sea back in 2008 filmmakers captured an enormous chunk of ice away the changes that we are witnessing are amazing none of us expected to see such changes in Greenland [Music] [Music] we are just two years into this five year long experiment to measure how much the oceans are melting away the ice around the edges of Greenland but we've already found out that glaciers all around Greenland sit in fjords that are much deeper than we previously knew that means more of the ice is in contact with the ocean water and more glaciers are threatened than we previously understood sometimes I think about the evidence that we have gathered over the past 2025 years even more on the impact of climate warming on the ice sheets and my kids and grandkids said let me look at me and say you knew this was happening what have you done to slow it down I study them and I reported the results to people I'm not sure that was enough but I did the best I could [Music] NASA's findings suggest that current predictions of how fast Greenland's glaciers are melting may be too conservative putting coastal cities from Miami to Mumbai at greater risk of catastrophic flooding similar forces could be at work on the other side of the planet in Antarctica where there is ten times as much ice you [Music] [Music] [Music] [Music] you you

Channel: NOVA PBS Official

Views: 86,934

Keywords: Greenland, GreenlandMelting, Glaciers, Climate, FRONTLINE PBS, NOVA PBS, FRONTLINE, NOVA, PBS, WGBH, Climatology, Climate Change, Ice, Arctic, Science, NOAA, NASA, Snow, Research, 360, Sea Level, Iceberg

Id: rFBBu6lxA6o

Length: 12min 17sec (737 seconds)

Published: Thu Sep 20 2018