Where Icebergs Go to Die

Today’s story is the answer to the October 2018 puzzler. which was also covered on WUWT

This could be a scene out of a spooky movie. But reality is just as morbid for this coffin-shaped iceberg. After 18 years at sea, B-15T has entered a region where Antarctic icebergs go to die.

On September 23, 2018, when an astronaut on the International Space Station shot this photograph, iceberg B-15T had already left the Southern Ocean. It was spotted in the South Atlantic between South Georgia and the South Sandwich Islands. The second image shows a wide view, acquired the same day by the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite. Icebergs like this are known to melt rapidly as they make their way north into warmer waters.

B-15T’s journey to this iceberg graveyard has been a long one. Its parent berg (B-15) first broke away from the Ross Ice Shelf in March 2000. It fractured over time into smaller bergs, many of which continued riding the Antarctic Coastal Current (counter-clockwise) around Antarctica.

By late 2017, the Weddell Sea gyre had redirected B-15T from its near circumnavigation and sent the berg drifting north. This third image was acquired in October 2017 by MODIS on NASA’s Aqua satellite. It shows the iceberg when it was near Elephant Island, an icy bit of rock located a few hundred kilometers north-northeast from the tip of the Antarctic Peninsula.

The Antarctic Circumpolar Current, which funnels through the Drake Passage, then steered the iceberg toward the east and its current location. Water at this latitude—about 54 degrees South—is generally warmer than the Southern Ocean and deadly for icebergs. NASA/UMBC glaciologist Chris Shuman noted that Southern Hemisphere winter was just ending when the astronaut spotted the berg, so the return of abundant sunlight could further warm the water around it. The lack of sea ice in the vicinity of B-15T implies that the water was above the freezing point.

The spooky shape of B-15T was acquired long before it moved into this iceberg graveyard. For more than a decade, B-15 had numerous collisions—smashing back into the Ross Ice Shelf where it originated, hitting bedrock along the coast, and bumping into other tabular icebergs. Such collisions can be strong enough to abruptly fracture the crystalline ice and produce linear edges—similar to the rectangular iceberg that debuted this month near the Larsen C ice shelf and iceberg A-68. That iceberg is visible in the photograph below, acquired October 16 during an Operation IceBridge science flight.

“This fracturing is akin to ‘cleaving’ a mineral crystal with a sharp tap of hammer,” Shuman said. Of course, the edges are not always so linear. Other bergs have edges that are curved. Some become jagged when the pull of gravity or the cutting action of waves causes ice to irregularly splinter.

“The coffin shape is an accident of time and space, given the approximately 18.5-year voyage of B-15T,” Shuman said. “We can only guess at the forces that have acted on this remnant of B-15 along the long way around Antarctica.”

Astronaut photograph ISS056-E-195042 was acquired on September 23, 2018, with a Nikon D5 digital camera using a 800 millimeter lens and is provided by the ISS Crew Earth Observations Facility and the Earth Science and Remote Sensing Unit, Johnson Space Center. The image was taken by a member of the Expedition 56 crew. The image has been cropped and enhanced to improve contrast, and lens artifacts have been removed. The International Space Station Program supports the laboratory as part of the ISS National Lab to help astronauts take pictures of Earth that will be of the greatest value to scientists and the public, and to make those images freely available on the Internet. Additional images taken by astronauts and cosmonauts can be viewed at the NASA/JSC Gateway to Astronaut Photography of Earth. NASA Earth Observatory images by Lauren Dauphin and Jeff Schmaltz, using MODIS data from NASA EOSDIS/LANCE and GIBS/Worldview. Airborne photograph by NASA/Jeremy Harbeck. Story by Kathryn Hansen.

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37 thoughts on “Where Icebergs Go to Die

  1. Iceberg death is always sad but it’s a part of life (albeit not of the life of the dead iceberg), and while we might wish upon a star that they could live forever, I always tell my kids that under the cruel logic of nature, immortality would leave no room for all the new icebergs. If an iceberg halves as it calves, is that an example of meiosis, mitosis or just a short-sighted question? Weep, weep for all the cryobiology I’ve forgotten since high school.

    • I, too, mourn this death. I can only hope this individual will ascend to iceberg heaven. It’s already been through hell.

      • When this iceberg is gone it will be gone forever. The space it took in nature will be a void less filled. It was translated into another form older than earth itself that now is free to infuse all on earth with its essence. We who are left behind can only hope the phases of its existence will contain and release the energy needed to help us all recycle the natural beauty of a polar state.

    • Well Brad Keyes, make up for cryobiology with a bit of history:

      The “Garthforce” sailed from England in 1921 with Captain R. D. Cruickshank in command. His wife
      travelled with him. Late in January 1922 the Garthforce was “running her easting down” for Australia. Cruick- shank was driving her hard in squally, misty weather. In the small hours of
      the morning she crashed full into an invisible, waiting berg…..Cruickshank fixed his position as
      eighty miles to the east of Prince Edward and Marion Islands….(Eight Bells at Salamander L. G Green).

      An iceberg big enough to severely damage an steel-hulled windjammer was clearly lurking a great way further North than S Georgia. Marion and Price Edward are roughly 47 S; 38 E…

      And there are many other records of similar occurrences in the days before radar, in the S Atlantic within 3 or 4 days sailing/steaming of Cape Town. One of Nelson’s Captains Edward Riou (killed at the Battle of Copenhagen), commanding HMS Guardian at the end of the 1700s, struck an iceberg South of Cape Town and brought her into that port after an epic survival battle.

    • “If an iceberg halves as it calves, is that an example of meiosis, mitosis or just a short-sighted question?”

      What about neuritis and neuralgia? Those with shingles would probably demand answers of you. Are you bigoted against roofies?

  2. Background reading

    This, and more, including photos:
    “You may think it would drift north, away from the continent, but icebergs this big don’t have an easy path. They crash and bounce along any relatively shallow region of the sea floor and wipe out anything in their way. Most people know trawling harms the sea floor; imagine the trail of damage 900 billion tonnes of ice scraping on the sea floor can leave.”

    • Damage is a subjective human interpretation. I expect that as this is an entirely natural and regular occurence it almost certainly makes some positive contribution to the normal state of the sea floor Perhaps by redistributing sea floor deposits mineral and organic back into the biology of the deep sea.
      The tricky bit is trying to interpret which human activities have neutral or beneficial effects. Neutral is a function of time scales. Virtually nothing we do to the planet will matter in 10 million years from now. If I’m wrong, feel free to look me up!

      • john

        If we sucked all the CO2 out the atmosphere as some propose we do (well partially) and destroyed all meaningful life on earth, 10 million years might not be long enough to repair the damage we did.

        I suspect it would though, and I do like your post.

  3. I think the turbulence from the South Sandwich Islands in the 2nd picture is pretty cool. Take a look at the enlarged pic for details.

  4. This iceberg, floating free, for 18 years still hasn’t succumbed to a warmer planet.

    If it takes this long to still not have melted, how long do the alarmist’s imagine it would take the Antarctic or Greenland to melt? What size is this compared to it’s origin?

      • It isn’t uncommon for icebergs to stay close to the Antarctic continent for a long time. There is a westward coastal countercurrent to the eastward Antarctic Cicumpolar Current.

        However the Antarctic peninsula interferes wth this simple system and therefore icebergs are often deflected northwards into warmer waters in this area. It was already known in the 19th century that there were occasional “epidemics” of icebergs that endangered shipping in the waters around Cape Horn.

      • The original Iceberg B-15 was the world’s largest recorded iceberg. It measured around 295 kilometres (183 mi) long and 37 kilometres (23 mi) wide, with a surface area of 11,000 square kilometres (4,200 sq mi)—larger than the whole island of Jamaica.
        It stayed grounded for a while and proceeded to break up into large pieces, the largest one B-15A has been well documented.
        https://upload.wikimedia.org/wikipedia/commons/thumb/0/00/B15a_a4.jpg/1920px-B15a_a4.jpg

        • “The original Iceberg B-15 was the world’s largest recorded iceberg. It measured around 295 kilometres (183 mi) long and 37 kilometres (23 mi) wide, with a surface area of 11,000 square kilometres (4,200 sq mi)—larger than the whole island of Jamaica.”

          How many iced lattes is that?

    • The B-9 iceberg calved in 1987 and is still in fairly good shape 31 years later. It is currently stranded in Commonwealth Bay, and as a matter of fact it was the presence this berg that messed things up for the “Ship of Fools”

  5. Over the years there have been serious proposals to tow tabular icebergs to Los Angeles. They’d be OK as long as they stayed in the cold Humboldt Current off the southern Pacific coast of South America, but would need insulation to survive the North Pacific, despite the cool California Current.

      • LA has managed to pillage and plunder enough fresh water from hither and yon to keep growing without towing ice from Antarctica. With nuclear power, they could desalinate sea water, but in today’s CA, nuke and fossil fuels are equally anathema.

        And any ocean-going tugs towing the bergs would of course also have to run on fossil fuels rather than wind or sun.

  6. So we get the names of the guys who took the airborne shots and NEO shots but the one from ISS was just “an astronaut”.

    Clearly care has been taken not to mention the person ( ie author ) of this photo.

    We even get to know what camera he used and what setting but his name is withheld. What is that about?

  7. given the huge amount of warming the planet has undergone in the last 18 years i find it hard to believe any lump of ice can last that long ,i mean look at the arctic sea ice, it has all melted according to prof. wadhams 😉 (hopefully no sarc tag needed)

  8. I suggest running a competition to find the most likely reason why this will be the source of extra problems because of global warming.

    My theory is that such icebergs are a temporary residence for wounded seabirds. Or Seabirdy McSeabirdface lost his way home after a long night out and having eaten too many fish to fly properly. The damage due to increased melting of such icebergs is, well, incalculable.

  9. Looks like a cheap alternative to expensive aircraft carriers. Unless it needs to go somewhere …

    (Recall comedian Jackie Mason: “I’ve got enough money to last me the rest of my life. Unless I need to buy something.”)

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