Skip to main content

Scientists Found the Deepest Land on Earth Hiding Beneath Antarctica's Ice

Map of Antarctica ice sheet topography.
The BedMachine map reveals ridges and valley's beneath Antarctica's ice.
(Image: © Mathieu Morlighem/UCI)

A new map of the mountains, valleys and canyons hidden under Antarctica's ice has revealed the deepest land on Earth, and will help forecast future ice loss.

The frozen southern continent can look pretty flat and featureless from above. But beneath the ice pack that's accumulated over the eons, there's an ancient continent, as textured as any other. And that texture turns out to be very important for predicting how and when ice will flow and which regions of ice are most vulnerable in a warming world. The new NASA map, called BedMachine Antarctica, mixes ice movement measurements, seismic measurements, radar and other data points to create the most detailed picture yet of Antarctica's hidden features.

Related: 50 Amazing Facts About Antarctica

"Using BedMachine to zoom into particular sectors of Antarctica, you find essential details, such as bumps and hollows beneath the ice that may accelerate, slow down or even stop the retreat of glaciers," Mathieu Morlighem, an Earth system scientist at the University of California, Irvine and the lead author of a new paper about the map, said in a statement.

The new map, published Dec. 12 in the journal Nature Geoscience, reveals previously unknown topographical features that shape ice flow on the frozen continent.

The previously unknown features have "major implications for glacier response to climate change," the authors wrote. "For example, glaciers flowing across the Transantarctic Mountains are protected by broad, stabilizing ridges."

Understanding how ice flows in Antarctica becomes increasingly important as Earth warms. If all of Antarctica's ice were to melt, it would raise global sea levels by 200 feet (60 meters), according to the National Snow and Ice Data Center. That isn't likely anytime soon, but even if small fractions of the continent were to melt, it would have devastating global effects. 

Included in the data is evidence for the deepest canyon on planet Earth. By studying how much ice flows through a particular, narrow region known as the Denman trough each year, the researchers realized it must dive at least 11,000 feet (3,500 meters) below sea level to accommodate all the frozen water volume. That's far deeper than the Dead Sea, the lowest exposed region of land, which sits 432 meters (1,419 feet) below sea level, according to the Israel Oceanographic and Limnological Research center.

The map offers a wealth of new information on precisely which regions of the continent's ice are at most risk of sliding into the ocean in the coming decades and centuries, the authors wrote.

Originally published on Live Science.

How it Works banner

Want more science? You can get 5 issues of our partner “How It Works” magazine for $5 for the latest amazing science news.  (Image credit: Future plc)
  • ty2010
    admin said:
    A new mapping effort revealed critical new details of Antarctica's hidden land.

    Scientists Found the Deepest Land on Earth Hiding Beneath Antarctica's Ice : Read more
    My main issue is with the 200 ft rise figure. If you took the entire land area of 5.5m sq mi, 8200 ft average elevation, down to sea level and spread it over the entire ocean of 140m sq mi it only comes to 145 ft. Sure there's going to be some additional from isostatic rebound but there's going to be sinking globally as well, this isn't even counting the expanding of the ocean's borders with the sea level rise. The isostatic figure shouldn't be included anyway as Canada is still recovering from the last ice age. Aside from some damming effects for land based ice, sea ice is a wash because it's already displacing it's volume in the ocean.
    Reply
  • Rathgic
    An example of how irrational the current science community can be.

    All ice that is currently below the current sea level is irrelevant in determining what happens to the sea level lF IT ALL MELTED.

    Why, as solid ice ..... if it is now below sea level, then if it melts it takes up no more room that it presently is ALREADY DISPLACING.
    Reply
  • sqlblindman
    Rathgic said:
    An example of how irrational the current science community can be.

    All ice that is currently below the current sea level is irrelevant in determining what happens to the sea level lF IT ALL MELTED.

    Why, as solid ice ..... if it is now below sea level, then if it melts it takes up no more room that it presently is ALREADY DISPLACING.
    An example of how ignorant those outside the science community, who think they actually know anything about science can be.
    Ice only displaces it's weight in water when it is FLOATING. So an ice cube melting in a cup of water does not change the level of the water. But an ice cube melting on a table ABSOLUTELY changes the level of the water on the table.
    This ice in this instance is not floating, but is sitting on a land mass. When it melts, sea level with rise.

    Now you know.
    Reply
  • Lilkittygirl
    Rathgic said:
    An example of how irrational the current science community can be.

    All ice that is currently below the current sea level is irrelevant in determining what happens to the sea level lF IT ALL MELTED.

    Why, as solid ice ..... if it is now below sea level, then if it melts it takes up no more room that it presently is ALREADY DISPLACING.


    I'm gonna break it down a little for you. A lot of the ice that is in Antarctica is not actually under the water. It sits on top of a massive landmass so it isn't displacing anything currently. Even being below sea level does not actually mean there is water displacement happening, canyons have no water in them for example or very little. (ex. Grand Canyon). So as they stated, if the ice were to melt it would significantly impacts the ocean's water levels due to the majority of ice being on top of land and not sitting floating in water.
    Reply
  • ty2010
    Lilkittygirl said:
    I'm gonna break it down a little for you. A lot of the ice that is in Antarctica is not actually under the water. It sits on top of a massive landmass so it isn't displacing anything currently. Even being below sea level does not actually mean there is water displacement happening, canyons have no water in them for example or very little. (ex. Grand Canyon). So as they stated, if the ice were to melt it would significantly impacts the ocean's water levels due to the majority of ice being on top of land and not sitting floating in water.
    See map, those canyons are not blocked from the ocean and will fill with water.
    Reply
  • ty2010
    sqlblindman said:
    An example of how ignorant those outside the science community, who think they actually know anything about science can be.
    Ice only displaces it's weight in water when it is FLOATING. So an ice cube melting in a cup of water does not change the level of the water. But an ice cube melting on a table ABSOLUTELY changes the level of the water on the table.
    This ice in this instance is not floating, but is sitting on a land mass. When it melts, sea level with rise.

    Now you know.
    The land it's sitting on is below sea level, that portion of the ice below sea level will occupy 9/10 the volume when melted, claims aren't to total ice volume on sub sea level land.
    Reply
  • physicitpeks
    Umm, let's say that Antarctica was a land mass where all the snow/ice "covering it" was below sea level and it came up to exactly sea level (like some god had taken a big knife and it cut if off there). Now let's say all of that snow/ice melts. Will the the surrounding ocean level rise, fall, or stay the same? Since snow/ice is just frozen water, and solid water is less dense than liquid water (that's why it rises to the surface), it seems to me that the snow/ice that turned into water would take up less room (would be more dense) than the snow/ice. Therefore, the ocean level would go down slightly. It would not be enough to counteract all the snow/ice that is currently covering the land mass of Antarctica if that were all to melt and flow into and thus raise the sea level. But be that as it may, the original poster is kind of correct when he stated:

    "All ice that is currently below the current sea level is irrelevant in determining what happens to the sea level lF IT ALL MELTED." <= It isn't totally irrelevant, since the melting of ice below sea level would contribute to lowering sea level

    "Why, as solid ice ..... if it is now below sea level, then if it melts it takes up no more room that it presently is ALREADY DISPLACING." <= that is a correct statement, in fact it actually will take up less room

    "
    An example of how irrational the current science community can be."
    I don't know that scientist don't know this. I suspect that good scientists do. So I don't really agree with the posters initial statement, unless it turns out the current science community doesn't realize this...
    Reply
  • sqlblindman
    ty2010 said:
    The land it's sitting on is below sea level, that portion of the ice below sea level will occupy 9/10 the volume when melted, claims aren't to total ice volume on sub sea level land.
    Of course the land it is sitting on is below sea level.
    You think the scientists aren't aware of that, or of what proportion are above and below the surface?

    Dunning, meet Kruger.
    Reply
  • ty2010
    Behavioral patterns are sometimes worse as they resist compensation across other behaviors.
    Reply
  • ty2010
    "...
    All ice that is currently below the current sea level is irrelevant in determining what happens to the sea level lF IT ALL MELTED.

    Why, as solid ice ..... if it is now below sea level, then if it melts it takes up no more room that it presently is ALREADY DISPLACING.
    "
    > talks about ice below sea level
    > you go on to argue about floating displacement

    The portion below sea level is displacement of sea water regardless if it is floating or not, unless an inland valley that's blocked off from the ocean is being discussed. In such an environment that would turn into a fresh water lake unless there's volcanic activity to dry.
    Reply