Finding warm water beneath Thwaites Glacier alarms scientists

Posted Jan 30, 2020 by Karen Graham
Scientists in Antarctica have recorded, for the first time, unusually warm water beneath a glacier the size of Florida that is already melting and contributing to a rise in sea levels.
On January 8  BAS tweeted:  Breakthrough at 590 m for the first hot water drilled access hole near t...
On January 8, BAS tweeted: "Breakthrough at 590 m for the first hot water drilled access hole near the grounding zone of #Thwaites Glacier."
British Antarctic Survey
Antarctica's Thwaites glacier covers more than 74,000 square miles (192,000 square kilometers) and is more than 900 miles (1,500 km) from the nearest U.S. and British Antarctic research bases. Also known as the "doomsday glacier," it earned this nickname because it is one of Antarctica's fastest melting glaciers.
After deploying Icefin, the robotic submarine equipped with high-definition video cameras, sonar and instruments for monitoring water flow, salinity, oxygen, and temperature, scientists were surprised to learn that waters at the glacier's grounding line were more than 2 degrees Celsius, or 3.6 degrees Fahrenheit, above the normal freezing point, per the New York Times.
Icefin image of sediments and rock in the ice at the grounding zone of Thwaites Glacier  Antarctica.
Icefin image of sediments and rock in the ice at the grounding zone of Thwaites Glacier, Antarctica.
MELT/Britney Schmidt
"Warm waters in this part of the world, as remote as they may seem, should serve as a warning to all of us about the potential dire changes to the planet brought about by climate change," David Holland, a lead researcher on the expedition and director of the Environmental Fluid Dynamics Laboratory at New York University, told the Chicago Tribune.
As readers may remember, the journey to collect data wasn't easy. The team, dubbed MELT, spent nearly two months in minus 22 F (minus 30 C) weather preparing for the project that entailed drilling a nearly 2,000-foot-long (600 meters) borehole in the ice of Thwaites Glacier.
Icefin was lowered into the borehole and had to travel a mile to the glacier's grounding line. While it puttered along, it constantly took measurements and images so that scientists could later map the area, as well as understand the temperatures and the changing landscape there, according to Live Science.
 Robotsicle   researcher Britney Schmidt s nickname for this photo. Icefin s  face  with instruments...
"Robotsicle," researcher Britney Schmidt's nickname for this photo. Icefin's "face" with instruments and cameras covered in ice after a research dive on a separate project. Icefin is prepping for a future trip to Jupiter's moon Europa to search for life in its vast ocean.
MELT/Britney Schmidt
It is unclear how fast the glacier is deteriorating - it could be a century or just a couple of decades. However, finding warm water at the glacier's grounding line forecasts a hastier demise. This is important information.
Studies have already shown that the Thwaites, along with the Pine Island Glacier and a number of smaller glaciers, acts as a brake on part of the much larger West Antarctic Ice Sheet. Together, the two biggest glaciers, Thwaites and Pine Island, are holding back ice that, if melted, would raise the world’s ocean levels by more than a meter, or about four feet.
“It certainly has a big impact on our U.S. coast and in many areas,” said Twila Moon, a researcher with the National Snow and Ice Data Center at the University of Colorado Boulder, who was not part of the expedition. With human-caused climate change being a factor, The biggest predictor of “how much ice we will lose and how quickly we will lose it,” Dr. Moon said, “is human action.”
Thwaites Glacier s outer edge. As the glacier flows into the ocean  it becomes sea ice and drives up...
Thwaites Glacier's outer edge. As the glacier flows into the ocean, it becomes sea ice and drives up sea level. Thwaites Glacier ice is flowing particularly fast, and some researchers believe it may have already tipped into instability or be near that point, though this has not yet been established.
NASA/James Yungel
IceFin came to life in the laboratory of Britney Schmidt, an ITGC co-investigator from the Georgia Institute of Technology. And the University should be very proud of what the robotic submarine accomplished in giving the world its first view of a major glacier's grounding line.
“Visiting the grounding line is one of the reasons work like this is important because we can drive right up to it and actually measure where it is,” said Schmidt. It's the first time anyone has done that or has ever even seen the grounding zone of a major glacier under the water, and that’s the place where the greatest degree of melting and destabilization can occur.”
“Icefin swam over 15 km (9.3 miles) round trip during five missions. This included two passes up to the grounding zone, including one where we got as close as we physically could to the place where the seafloor meets the ice,” said Schmidt.