NASA – Largest glacier in Greenland is growing for third year in a row

The height of Jakobshavn glacier in western Greenland has increased by as much as 30 meters (98 feet) per year in some areas.

That’s about the height of a 10-story building … per year!The thickening is occurring across an increasingly wide area.

Although the glacier has spent decades in retreat, scientists observed an unexpected advance between 2016 and 2017. In addition to growing toward the ocean, the glacier was found to be slowing and thickening.

 

The image above, acquired on June 6, 2019 by the Operational Land Imager (OLI) on Landsat 8, shows a natural-color view of the glacier.

Scientists attribute the change to cool ocean waters

“The third straight year of thickening of Greenland’s biggest glacier supports our conclusion that the ocean is the culprit,” said Josh Willis, an ocean scientist at NASA’s Jet Propulsion Laboratory and principal investigator of the Oceans Melting Greenland (OMG) mission.

The maps below show how the glacier’s height changed between March 2016 and 2017 (top); March 2017 and 2018 (middle); and March 2018 and 2019 (bottom). The elevation data come from a radar altimeter that has been flown on research airplanes each spring as part of OMG. Blue areas represent where the glacier’s height has increased, in some areas by as much as 30 m (98 feet) per year.

 

The change is particularly striking at the glacier’s front (solid blue area on the left) between 2016 and 2017. That’s when the glacier advanced the most, replacing open water and sea ice with towering glacial ice. The glacier has not advanced as much since then, but it continues to slow and thicken.

Willis and colleagues think the glacier is reacting to a shift in a climate pattern called the North Atlantic Oscillation, which has brought cold water northward along Greenland’s west coast. Measurements of the temperatures collected by the OMG team show that the cold water has persisted.

The team will go back to Greenland in August.

NASA Earth Observatory images by Joshua Stevens, using Landsat data from the U.S. Geological Survey, and data courtesy of Josh Willis/NASA JPL and the Oceans Melting Greenland (OMG) Program.

https://earthobservatory.nasa.gov/images/145185/major-greenland-glacier-is-growing

Thanks to Guy Wilson for this link

 


13 thoughts on “NASA – Largest glacier in Greenland is growing for third year in a row”

  1. https://www.nytimes.com/2019/06/17/climate/greenland-ice-sheet-melting.html

    Someone is lying. Who?

    Melting last Wednesday was the most extensive, at 275,000 square miles, or about 45 percent of the surface, said Marco Tedesco, a geophysicist at the Lamont-Doherty Earth Observatory, which is part of Columbia University.

    That represents a record early date for such extensive melting, which has been measured by satellites since 1979. In 2012, an exceptionally warm year in the Arctic, there was slightly greater melting a few days later in June.

    • Use of the Times article is a joke. Why not cut it down to it was sunny in June more than other years. 45% of surface showing melt, non quantified as to volume, refreeze, or runoff. This is compared to a research piece showing 3 years of comparable data of thickness and can be inferred increased volume of Ice. So the increased volume over the last three years would have “withdrawn” liquid from the ocean no? Surface melt with no real measurement is meant to be a rebuttal argument so “someone is lying”. I’m tired of non logical statements of obfuscation passing as something meaningful.

      Will

  2. They might want to change the name of their mission to Ocean Maybe Freezing Greenland, OMFG. Amazing info, thanks Robert!

  3. looks a bit like OMG project is a misnomer as the oceans are blamed for colder waters.. which is a bit/LOT stupid as the glaciers form before they HIT the damned oceans.
    .same time as theyre still flogging warming waters melting arctic, woe woe all is lost etc, saw yet another the ice has melted item and looking forward to the next set of gullible fools to try n row/sail through..the last lot went very quiet rather quickly,

    • Laurel,

      The Jakobshavn is a tidewater glacier. While there is still a lot of research to be done to better understand their process of advance and retreat, it is known that these glaciers are very sensitive to the water temperatures in their fjords.

      Warmer water temperatures set up stronger convection currents which lead to faster calving and quick retreats. Even worse is what happens when the surface thins from either over-advance or extended periods of negative mass balance. Thinning can cause the ice to lose grounding and float in the fjord. This sets up a very unstable situation of calving and very fast retreat.

      It is certainly true that the accumulation zone for the Jakobshaven is well inland, but the tidewater portion can give us a better understanding of glacier dynamics in timescales fathomable by individual research scientists snd interested lay-folk alike.

  4. I read the original article and the researchers seem to be missing something. Where they note that sea surface temp seems to be cooling, they did not mentioned if the air temp was cooling.
    The rate of flow and the fascinating increase in thickness is likely due to the history of temps and snow deposition away up stream and back in time.
    They should have explained more than that the sea temp was decreasing.

    • Bob,

      Glacier dynamics are dominated by mass balance. While air temps are a factor in the summertime losses, winter accumulation upstream of the Jakobshavn has been dominant the past few years.

      Tidewater glaciers often show dynamic oscillations between advance and rapid retreat. Until a few years ago the Jakobshavn was in a fast retreat mode. It stopped its rapid calving once it retreated to the point where the glacier was grounded and no longer floating.

      It has been interesting to watch the advance and now thickening of this advancing terminus. Tony Heller has some pictures on his site that show the advance from an aerial or satellite view.

  5. I saw this great headline from a global warming website.

    “Greenland glacier has grown for a third year but will soon melt again…”

    Reads more like they are hoping and praying it will melt again, in order to save all their government grants and study fees.

  6. Glaciers only grow if there is more snow or ice feeding them either from falling or sublimation from the moisture in the air. NASA is trying to down play this with cool water moving north or south like OH its only temporary its really warming!

  7. on the same sh*t different day i hear theyre trying to panic people saying the himalayas are melting again
    after 70foot or more of snow in some spots and hundreds of percent above avg…if theres melt its prob new snow not glaciers
    but then that’d ruin a good panic panic!! meme

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