Nav: Home

Update on the Larsen-C iceberg breakaway

August 02, 2017

The largest remaining ice shelf on the Antarctic Peninsula lost 10% of its area when an iceberg four times the size of London broke free earlier this month.

Since the 12 July 2017 breakaway Dr Anna Hogg, from the University of Leeds and Dr Hilmar Gudmundsson, from the British Antarctic Survey (BAS), have continued to track the iceberg - known as A68 - using the European Space Agency (ESA) and European Commission's Copernicus Sentinel-1 satellite.

Their observations show that since the calving event, the berg has started to drift away from the Larsen-C, with open ocean clearly visible in the ~ 5 kilometre gap between the berg and the ice-shelf.

A cluster of over 11 'smaller' icebergs have also now formed, the largest of which is over 13 km long. These 'bergy bits' have broken off both the giant iceberg and the remaining ice-shelf.

Dr Hogg, an ESA Research Fellow in the Centre for Polar Observation and Modelling (CPOM) at Leeds said: "The satellite images reveal a lot of continuing action on Larsen-C Ice Shelf. We can see that the remaining cracks continue to grow towards a feature called Bawden Ice Rise, which provides important structural support for the remaining ice shelf.

"If an ice shelf loses contact with the ice rise, either through sustained thinning or a large iceberg calving event, it can prompt a significant acceleration in ice speed, and possibly further destabilisation. It looks like the Larsen-C story might not be over yet."

Reporting this week in the journal Nature Climate Change Dr Hogg and Dr Gudmundsson, examine the events leading up to this dramatic natural phenomenon and discuss how calving of huge icebergs affects the stability of Antarctic ice shelves.

Their article asserts that a calving event is not necessarily due to changes in environmental conditions and may simply reflect the natural growth and decay cycle of an ice shelf.

Dr Gudmundsson said: "Although floating ice shelves have only a modest impact on of sea-level rise, ice from Antarctica's interior can discharge into the ocean when they collapse. Consequently we will see increase in the ice-sheet contribution to global sea-level rise.

"With this large calving event, and the availability of satellite technology, we have a fantastic opportunity to watch this natural experiment unfolding before our eyes. We can expect to learn a lot about how ice shelves break up and how the loss of a section of an ice shelf affects the flow of the remaining parts."

Ice-shelf retreat on the Antarctic Peninsula, has been observed throughout the satellite era - about 50 years. Large sections of the Larsen Ice Shelf A and B, and the Wilkins1 ice-shelf collapsed in a matter of days in 1995, 2002, and 2008, respectively.

Geological evidence suggests that ice-shelf decay of this magnitude is not unprecedented, however, prior to 2002 the Larsen-B ice shelf remained intact for the last 11,000 years. While Antarctic ice shelves are in direct contact with both the atmosphere and the surrounding oceans, and thus subject to changes in environmental conditions, they also go through repeated internally-driven cycles of growth and collapse.
-end-
Further information:

New animation, GIF and PNG available for download at: https://goo.gl/FyR5V8

Credits and captions:
Animation: Hogg_NCC_Lc.mp4
Credit: A.E. Hogg, CPOM, University of Leeds.
Caption: The story of the giant iceberg calving event on the Larsen-C Ice-Shelf.

GIF: Hogg_NCC_Lc_coherence.gif
Credit: A.E. Hogg, CPOM, University of Leeds.
Caption: Sentinel-1 data shows network of cracks grow on the Larsen-C Ice-Shelf, before the colossal iceberg broke free.

Image: LarsenC-S1-20170730.png
Credit: A. Fleming, British Antarctic Survey.
Caption: View of the A68 iceberg from a European Copernicus Sentinel-1 satellite image acquired on 30.7.2017.

Dr Anna Hogg and Dr Hilmar Gudmundsson are available for interviews and additional information.

To get in touch with Dr Hogg please contact: Anna Martinez, press officer, University of Leeds
tel:+44 (0)113 343 4196; email: a.martinez@leeds.ac.uk

To get in touch with Dr Hilmar Gudmundsson please contact: Sarah Vincent, Senior Communications Manager, British Antarctic Survey:
tel +44 (0)1223 221445; mobile +44 (0)7850 541910; email sarnce@bas.ac.uk

Broadcast-quality footage of Larsen Ice Shelf and additional images are available from British Antarctic Survey Press Office

Impacts of the Larsen-C ice-shelf calving event by Anna E Hogg and G Hilmar Gudmundsson will be published on Nature Climate Change on 2 August 2017 (PDF available on request)
URL: http://www.nature.com/nclimate/journal/v7/n8/full/nclimate3359.html

University of Leeds

The University of Leeds is one of the largest higher education institutions in the UK, with more than 33,000 students from 147 different countries, and a member of the Russell Group of research-intensive universities.

We are a top 10 university for research and impact power in the UK, according to the 2014 Research Excellence Framework and we are The Times and The Sunday Times University of the Year 2017. Additionally, the University has been awarded a gold rating by the Government's Teaching Excellence Framework recognising its 'consistently outstanding' teaching and learning provision. http://www.leeds.ac.uk

British Antarctic Survey (BAS), an institute of the Natural Environment Research Council (NERC), delivers and enables world-leading interdisciplinary research in the Polar Regions. Its skilled science and support staff based in Cambridge, Antarctica and the Arctic, work together to deliver research that uses the Polar Regions to advance our understanding of Earth as a sustainable planet. Through its extensive logistic capability and know-how BAS facilitates access for the British and international science community to the UK polar research operation. Numerous national and international collaborations, combined with an excellent infrastructure help sustain a world leading position for the UK in Antarctic affairs. For more information visit http://www.bas.ac.uk@basnews

University of Leeds

Related Ice Shelf Articles:

Antarctic ice rift close to calving, after growing 17km in 6 days -- latest data from ice shelf
The rift in the Larsen C ice shelf in Antarctica has grown by 17km in the last few days and is now only 13km from the ice front, indicating that calving of an iceberg is probably very close, Swansea University researchers revealed after studying satellite data.
Off-the-shelf, power-generating clothes are almost here
A lightweight, comfortable jacket that can generate the power to light up a jogger at night may sound futuristic, but materials scientist Trisha Andrew at UMass Amherst could make one today.
Irreversible ocean warming threatens the Filchner-Ronne Ice Shelf
By the second half of this century, rising air temperatures above the Weddell Sea could set off a self-amplifying meltwater feedback cycle under the Filchner-Ronne Ice Shelf, ultimately causing the second-largest ice shelf in the Antarctic to shrink dramatically.
Shelf sediments reveal climate shifts through the eons
Climate change around Antarctica can severely affect Australia's rainfall and even influence the distribution of wet and dry zones across southeast Asia, an international study has revealed.
West Antarctic ice shelf breaking up from the inside out
A key glacier in Antarctica is breaking apart from the inside out, suggesting that the ocean is weakening ice on the edges of the continent.
Ice shelf vibrations cause unusual waves in Antarctic atmosphere
Ice shelf vibrations cause unusual waves in Antarctic atmosphere.
Tracking the amount of sea ice from the Greenland ice sheet
The Greenland ice sheet records information about Arctic climate going back more than 120.000 years.
Improved knowledge of shelf life of food
We should avoid food waste but, on the other hand, not risk food poisoning from eating food that is way past its sell-by date.
Changes in Antarctic sea ice production due to surrounding ice conditions.
Antarctic sea ice production spanning more than 20 years has been understood through the analysis of satellite observations using specially developed techniques.
Colossal Antarctic ice-shelf collapse followed last ice age
A new PNAS study is providing clues about how Antarctica's nation-sized Ross Ice Shelf might respond to a warming climate.

Related Ice Shelf Reading:

Shelf Ice (Ray Elkins Thriller Series)
by Writers & Editors, LLC

It’s February along the shores of Northern Lake Michigan. A heavy blanket of snow has been building up in the woods since early November and the inland lakes have had a solid covering of ice since December.Shelf ice, stacked ten or fifteen feet in places, has been building on Lake Michigan for weeks.
Sheriff Ray Elkins, responding to a late-night home invasion call, discovers the brutal murder of a local artist at her home deep in the woods. Elkins works to understand complex lives and relationships as he pursues a brilliant and brutal adversary. View Details


The Ice Shelf (The Fischermann Family Book 1)

Visiting his mountain cabin after his wife’s death, Cornelius Fischermann suffers a skiing accident and must decide whether to go on living, himself. View Details


Arctic Ice Shelves and Ice Islands (Springer Polar Sciences)
by Luke Copland (Editor), Derek Mueller (Editor)

This book provides an overview of the current state of knowledge of Arctic ice shelves, ice islands and related features. Ice shelves are permanent areas of ice which float on the ocean surface while attached to the coast, and typically occur in very cold environments where perennial sea ice builds up to great thickness, and/or where glaciers flow off the land and are preserved on the ocean surface. These landscape features are relatively poorly studied in the Arctic, yet they are potentially highly sensitive indicators of climate change because they respond to changes in atmospheric,... View Details


On the Ice With... Tara Lipinski (Matt Christopher Sports Bio Bookshelf)
by Matt Christopher (Author)

Describes the life and skating career of the young woman who won a gold medal in figure skating at the 1998 Olympics. View Details


A Storm of Swords (A Song of Ice and Fire, Book 3)
by George R. R. Martin (Author)

Of the five contenders for power, one is dead, another in disfavor, and still the wars rage as violently as ever, as alliances are made and broken. Joffrey, of House Lannister, sits on the Iron Throne, the uneasy ruler of the land of the Seven Kingdoms. His most bitter rival, Lord Stannis, stands defeated and disgraced, the victim of the jealous sorceress who holds him in her evil thrall. But young Robb, of House Stark, still rules the North from the fortress of Riverrun. Robb plots against his despised Lannister enemies, even as they hold his sister hostage at King’s Landing, the seat of... View Details


Unknown Waters: A First-Hand Account of the Historic Under-ice Survey of the Siberian Continental Shelf by USS Queenfish (SSN-651)
by Dr. Alfred S. McLaren (Author), William R. Anderson (Foreword)

Charting the Siberian continental shelf during the height of the Cold War This book tells the story of the brave officers and men of the nuclear attack submarine USS Queenfish (SSN-651), who made the first survey of an extremely important and remote region of the Artic Ocean. The unpredictability of deep-draft sea ice, shallow water, and possible Soviet discovery, all played a dramatic part in this fascinating 1970 voyage. View Details


The Lands of Ice and Fire (A Game of Thrones): Maps from King's Landing to Across the Narrow Sea (A Song of Ice and Fire)
by George R. R. Martin (Author)

Perfect for fans of A Song of Ice and Fire and HBO’s Game of Thrones, this collection of full-color maps is stunningly illustrated and ideal for framing.

George R. R. Martin’s beloved series is bursting with a variety and richness of landscapes—from bitter tundra to arid wasteland and everything in between—that provide a sense of scale unrivaled in contemporary fantasy. Now this dazzling set of maps, featuring original artwork from illustrator and cartographer Jonathan Roberts, transforms Martin’s epic saga into a world as fully realized as the one around... View Details


Beartown: A Novel
by Fredrik Backman (Author)

NAMED ONE OF THE BEST BOOKS OF THE YEAR BY: LibraryReads BookBrowse Goodreads

“You’ll love this engrossing novel.” —People

The bestselling author of A Man Called Ove returns with a dazzling, profound novel about a small town with a big dream—and the price required to make it come true.

People say Beartown is finished. A tiny community nestled deep in the forest, it is slowly losing ground to the ever-encroaching trees. But down by the lake stands an old ice rink, built... View Details


Ice Pops!: 50 delicious fresh and fabulous icy treats
by Cesar Roden (Author), Nadia Roden (Author)

Meet the hottest ices in town: 50 artisanal ice pops, lovingly made with fresh fruit and bursting with spices, herbs, coffee, chocolate, and nuts! Along with their unique recipes, authors Nadia and Cesar Roden—an aunt-and-nephew team—give fun techniques for working with molds, choosing sticks, creating stripes and swirls, suspending ingredients, and adding decorations. The lusciously lickable treats include Lemon and Ginger, Drenched Watermelon, Sweet Sherry & Raisin, Butterscotch, Minted Milk, Vietnamese Coffee, and (for the purist) a simple, delicious Chocolate. View Details


Ice Kissed: The Kanin Chronicles (From the World of the Trylle)
by Amanda Hocking (Author)

In the majestic halls of a crystal palace lies a secret that could destroy an entire kingdom…

Bryn Aven refuses to give up on her dream of serving the kingdom she loves. It's a dream that brings her to a whole new realm…the glittering palace of the Skojare.

The Skojare people need protection from the same brutal enemy that's been threatening the Kanin, and Bryn is there to help. Being half Skojare herself, it's also a chance for her to learn more about her lost heritage. Her boss Ridley Dresden is overseeing the mission, but as their undeniable attraction heats up, their... View Details

Best Science Podcasts 2018

We have hand picked the best science podcasts for 2018. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Inspire To Action
What motivates us to take up a cause, follow a leader, or create change? This hour, TED speakers explore stories of inspirational leadership, and what makes some movements more successful than others. Guests include high school history teacher Diane Wolk-Rogers, writer and behavioral researcher Simon Sinek, 2016 Icelandic presidential candidate Halla Tómasdóttir, professor of leadership Jochen Menges, and writer and activist Naomi Klein.
Now Playing: Science for the People

#474 Appearance Matters
This week we talk about appearance, bodies, and body image. Why does what we look like affect our headspace so much? And how do we even begin to research a topic as personal and subjective as body image? To try and find out, we speak with some of the researchers at the Centre for Appearance Research (CAR) at the University of the West of England in Bristol. Psychology Professor Phillippa Diedrichs walks us through body image research, what we know so far, and how we know what we know. Professor of Appearance and Health Psychology Diana Harcourt talks about visible...