Please select your home edition
North Sails 2021 LEADERBOARD

Antarctic floating ice walls protect against warmer seas

by CSIRO 2 Mar 2020 16:48 UTC
Getz ice shelf © Anna Wåhlin

A recent study published in the journal Nature has explored the physics behind the warming ocean currents around the Antarctic coast, finding floating ice walls offer some protection to the ice sheet by limiting the amount of ocean heat that reaches the ice.

The research was led by the University of Gothenburg and used data and research from Australia's National Science Agency, CSIRO.

Floating ice walls - the edge of the floating ice shelf - are connected to landmass. Icebergs detach from ice shelves to join the ocean.

The Antarctic ice sheet contains enough ice, if melted, to raise global sea levels by tens of metres so improving our understanding of the stability of the Antarctic ice sheet - and the processes which could slow or speed its rate of melt - are of critical importance globally.

Researchers found that floating ice walls partly deflect warm ocean currents that would otherwise penetrate cavities beneath the floating portions of the ice sheet.

CSIRO researcher at the Centre for Southern Hemisphere Ocean Research (CSHOR), Dr Laura Herraiz-Borreguero said one important control on ice loss from Antarctica was what happened where the ice sheet meets the ocean, where a large amount of ice melts.

"The Antarctic ice sheet reaches the ocean through ice shelves, which are the floating edges of the ice sheet," Dr Herraiz-Borreguero said.

"Like a dam wall, these ice shelves slow down the rate at which grounded ice is discharged to the ocean, where it melts and contributes to sea level rise."

The question of how warm ocean currents made their way to the ice sheet, beneath the floating ice shelves, has been a long unanswered question for researchers.

More knowledge has now been obtained by studying data collected from instruments that Dr Herraiz-Borreguero and her colleagues placed in the ocean in front of Getz glacier ice shelf in West Antarctica.

The Getz glacier culminates in a vertical edge, a floating wall of ice that continues 300 to 400 metres down into the ocean.

Warm ocean currents flow beneath this edge, towards the deeper grounded ice.

The researchers found that the warm ocean currents were blocked by the floating ice edge, which limited the extent to which the warm ocean could reach the ice.

The floating ice blocks about two thirds of the thermal energy carried by the ocean currents, which travels up towards the Antarctic ice sheet from the deep Southern Ocean.

The results of the study have provided researchers with a greater understanding of how glacier areas like the Getz work.

"Our work highlights the importance of the floating ice shelves, and in particular, their ice fronts, as key areas that should be closely monitored," Dr Herraiz-Borreguero said.

"If the ice front walls were to thin and disappear, a much greater portion of ocean heat would be delivered towards the grounded Antarctic ice."

Researchers believe the studies provided them with significantly better tools to be able to predict future sea level rise.

Related Articles

Wooden Boat Festival is cancelled
A heavy heart and despite our best efforts, we are cancelling this year's Wooden Boat Festival It's with a heavy heart that despite our best efforts we are cancelling this year's Wooden Boat Festival. It's a big shift since last week's announcement of our advanced safety protocols Posted on 28 Aug
Introduction to ICAN Foundation
ICAN Foundation builds on the fundamentals of "I CAN DO THIS!" A passionate South African sailor and two sea-loving philanthropists developed the I CAN Foundation (I CAN) - a transformative at-sea mentor experience for young adults aging out of the U.S. foster care system. Posted on 25 Aug
Outremer showcases blue water sailing catamarans
One of the world's leading builders of reliable blue water sailing catamaran For the first time in two years one of the world's leading builders of reliable blue water sailing catamarans Outremer will showcase its latest models, including two world premieres, at the Cannes Yachting Festival, taking place from the 7-12 September. Posted on 24 Aug
Norwegian Cruising Guide updated volume 2
Ready to order at Datema Amsterdam We last wrote a month ago when we published a huge update to Volume 2. We are now pleased to report that the updated Volume 2, along with the other four volumes, are ready to order at Datema Amsterdam. Posted on 22 Jul
NARC Rally to sail again in October
Boats heading south can leave from Newport, R.I. and Chesapeake Bay Area Want to cruise south for the Winter? Do it with other like-minded sailors by joining the North American Rally to the Caribbean (NARC) Posted on 15 Jul
Whale world record and power of citizen science
The observations over this record-breaking time span were made by a combination of scientists A sperm whale has been observed in the Azores archipelago in the middle of the Atlantic ocean over a 34 year time span, setting an observation record in the Atlantic and very possibly the world. Posted on 12 Jun
Classic Maxi Cadamà celebrates her 50th birthday
The world's only wooden Maxi for the physically impaired Cadamà, the world's only wooden Maxi for the physically impaired, races with a mixed crew of wheelchair-bound and able-bodied sailors. This solid, two masted yacht was built 50 years ago in mahogany and iroko by the Beconcini Yard in La Spezia. Posted on 18 May
Panama Canal increases fees
Transit reservation and OMS fees to reflect growing demand Increases were announced but until now were never quantified. Transit service fees increase for yachts. Posted on 15 Apr
The best sailing destinations for family vacations
Picture yourself cruising the open sea, wind in your hair Often, the first thing that comes to mind when you hear vacation is a trip you take in a car or a plane. But what about a private boat? Picture yourself cruising the open sea, wind in your hair, fewer people to mingle with Posted on 6 Apr
TDoS launches the Aegir 2.0
The yacht with lowest possible environmental footprint Aegir 2.0 is the name of the wind-powered trimaran designed by TDoS which is an upgraded version of the Aegir, which was launched in 2019. The luxurious sailing yacht with green technology will make her the cleanest possible superyacht to date. Posted on 18 Mar
Upffront 2020 Foredeck Club SW FOOTERStoneways Marine 2021 - FOOTERNautical ID 2021 - FOOTER