Why Has A Maine-Sized Gigantic Hole Opened in Antarctic Weddell Sea?
© 2017 by Linda Moulton Howe
“It is quite remarkable. It looks like you just punched
a hole in the ice” the size of Maine!”
- Kent Moore, Ph.D. Atmospheric Physicist, Univ. of Toronto-Mississauga, Canada
An image of the mysterious Maine-size hole in the sea ice (blue outline
at center) on the edge of the Weddell Sea, Antarctica. Image:
MODIS-Aqua via NASA Worldview.
The Weddell Sea is marked by red circle between Antarctic Peninsula and
Coats Land of East Antarctica. The South Pole is red circle at center of map.
October 17, 2017 Weddell Sea, Antarctica - September was frigid winter to early spring in Antarctica and there should have been solid, thick ice across all of the Weddell Sea (larger red circle) between the Antarctic Peninsula and Coats Land in East Antarctica. But a few weeks ago, a surprising and mysterious huge hole appeared right in the middle of the icy sea.
The huge Maine-sized ice hole was discovered by a robotic float machine that was moving underneath the ice for researchers. Atmospheric physicist Kent Moore, Ph.D., in the Department of Chemical and Physical Sciences at the University of Toronto in Mississauga, Canada, said: “In the depths of winter, for more than a month now, we've had this huge area of open water. This is hundreds of kilometers from the ice edge. If we didn't have a satellite, we wouldn't know it was there. It is quite remarkable. It looks like you just punched a hole in the ice.”
This mysterious huge hole in the middle of the Weddell Sea is about
30,000 square miles, or the size of the state of Maine. It's the largest
hole in the Weddell Sea since the 1970s. Image by NASA Worldview.
Last year there was another mysterious hole in the Weddell Sea provoking Prof. Moore and other scientists to wonder if global climate change has something to do with the mystery. Technically when open water persists in what should be solid ice, it's called a “polyna.” But usually the Weddell Sea is solid ice in the Antarctic winter, so the back-to-back holes last year and this year stand out as unusual.
“We don’t really understand the long-term impacts this repeating polynya will have,” Prof. Moore said.
Weddell Sea History
Scientists report that the Weddell Sea between the Antarctic Peninsula and Coats Land of East Antarctica is the clearest water of any sea on Earth. Weddell Sea water is compared to the clarity of distilled water.
Sailers in the 1940s to 1950s described sailing on the Weddell Sea as treacherous in which “flash freezes” could suddenly trap ships in ice floes. Further, sailors told stories of “green-haired mermen” in the icy waters.
Merman of the Weddell Sea in ink drawing from 19th to 20th centuries
by Arthur Rackham. Mermen are legendary creatures who have the form
of a male human from the waist up and are fish-like from the waist down,
having scaly fish tails in place of legs. In Medieval Europe, mermen
were thought responsible for violent storms and sinking ships.
Back in the 1970s, a previous smaller hole in the Weddell Sea ice mysteriously appeared in the same location at the center of the sea two times. Then never again until 2016 and 2017. Using observations from satellites and deep sea robots, Moore and his collaborators are working to answer some of the questions. “Compared to 40 years ago, the amount of data we have is amazing,” he said, and could keep building a picture of a persistent warming Earth future of increasing ice melt.
Larsen C Iceberg the Size of Delaware
Broke Off Antarctic Peninsula in July 2017
Update - July 12, 2017 - Larsen C Iceberg Bigger Than Delaware
The final split was detected by NASA's Aqua satellite and announced today, Wednesday, July 12. Now there is worry that the trillion ton iceberg could drift into shipping lanes. This is the third gigantic ice shelf to collapse from the Antarctic Peninsula since 1995.
Finally Breaks Off Antarctic Peninsula.
“Current estimates are that if all the glacier ice that the Larsen C ice shelf
has kept from getting into the ocean is suddenly freed to move forward,
global ocean waters will rise 4 inches (10 cm).”
- The U. K. MIDAS Project
NASA Suomi VIIRS panchromatic image from July 12 2017,
confirming the trillion-ton-iceberg has broken off the Antarctic Peninsula.
Larsen C floats on the sea, so the Delaware-size ice chunk ready to calve won't cause sea levels to rise. However, Larsen C has long been fed by glaciers that are on land above sea level on the Antarctic Peninsula. The problem is that when Larsen C splits off, those glaciers can flow more rapidly into the ocean from land and that will cause seas to rise. Current estimates are that if all the glacier ice that the Larsen C ice shelf has kept from getting into the ocean is suddenly freed to move forward, global ocean waters will rise 4 inches (10 cm).
Antarctica's Larsen C Ice Shelf Is 2,000
Square Miles of Ice That Broke Off.
For further information about Antarctica, please see reports in the Earthfiles Archive organized in chronological order from 1999 to 2016 ongoing of which a few are listed here.
MIDAS Project, "Larsen C Ice Shelf Poised to Calve," January 5, 2017, by Adrian Luckman and MIDAS Team: http://www.projectmidas.org/blog/larsen-c-ice-shelf-poised-to-calve/
"Warmer Oceans Driving Antarctic Peninsula Glacier Melt," CarbonBrief, July 14, 2016: https://www.carbonbrief.org/warmer-oceans-driving-antarctic-peninsula-glacier-melt-study-says
"Mysterious Winds Cause Rapid Melting of antarctic Ice," November 15, 2016, National Geographic: http://news.nationalgeographic.com/2016/11/foehn-winds-melt-ice-shelves-antarctic-peninsula-larsen-c/