Nav: Home

Thousands of meltwater lakes mapped on the east Antarctic ice sheet

September 26, 2019

The number of meltwater lakes on the surface of the East Antarctic Ice Sheet is more significant than previously thought, according to new research.

A study led by Durham University, UK, discovered more than 65,000 supraglacial lakes using high-resolution satellite imagery covering five million square kilometres of the ice sheet, including areas where surface melting was previously thought to be less intense.

This is the first time that researchers have been able to map the widespread distribution of lakes across a vast area of the East Antarctic Ice Sheet - the world's largest ice mass - within a single melt year.

Although most of the ice sheet is incredibly cold, with temperatures plummeting to below -40 degrees Celsius in winter, summer temperatures can often reach above zero and cause surface melting. The study shows that meltwater lakes are forming in most coastal areas of the ice sheet, suggesting that East Antarctica could be more susceptible to the effects of a warming climate than previously thought.

The findings are published in the journal Scientific Reports.

The researchers looked at satellite images acquired in January 2017 during the East Antarctic Ice Sheet's summer melt season.

The images showed that meltwater lakes often cluster just a few kilometres from where the ice sheet begins to float on the sea, but some can exist hundreds of kilometres inland and at quite high elevations, up to 1,000m.

About 60 per cent of lakes develop on floating ice shelves, including some potentially at risk of collapse if the meltwater lakes become large enough to cause fracturing and drain through the ice.

This new study allowed the researchers to see where lakes are forming in the highest densities due to surface melting and which parts of the ice sheet might be most vulnerable to climate change.

Many of the lakes were the size of a standard swimming pool while the largest measured over 70 square kilometres.

Lead author Professor Chris Stokes, in the Department of Geography, Durham University, said: "We've known for some time that lakes are forming in East Antarctica, but we were surprised at quite how many had formed and all around the ice sheet margin.

"The density of lakes in some regions is similar to the densities we've observed on the Greenland Ice Sheet and on the Antarctic Peninsula, which are generally viewed as much warmer.

"It's concerning because we know that in other areas large numbers of lakes draining can fracture apart floating ice shelves, causing the inland ice to speed-up."

The researchers said the number of lakes mapped was a minimum as some small lakes might have been missed, while others might have been bigger in December or February.

Professor Stokes added: "This dataset should help us better understand why lakes are forming where they are and that will help us predict how the distribution of lakes will change in the future, especially if air temperatures warm. Whilst there is no imminent threat to the stability of the ice sheet, our study has shown which areas we should be keeping an eye on over the next few years and beyond."

Co-author Dr Amber Leeson, of the Lancaster Environment Centre, Lancaster University, UK, said: "At the opposite end of the Earth, we've seen Greenland's population of supraglacial lakes spread inland as air temperatures have risen, and we're concerned about the potential implications for enhanced melting and ice loss there. Until recently we assumed that East Antarctica was too cold to be similarly vulnerable, but this work shows that there may be closer parallels here to our observations on Greenland than previously thought."

Co-author Dr Stewart Jamieson, in the Department of Geography, Durham University, said: "At a time where the pressure to act on climate change is increasing, it's more important than ever to establish baseline measurements against which future change can be compared - this study will enable just that in relation to surface melting at the edges of the world's largest ice sheet."
-end-
The satellite imagery used in the study was obtained from the United States Geological Survey Earth Resources Observation Science Centre and the Copernicus Open Access Hub.

The research was funded by the UK Natural Environment Research Council. ENDS

Durham University

Related Climate Change Articles:

Fairy-wrens change breeding habits to cope with climate change
Warmer temperatures linked to climate change are having a big impact on the breeding habits of one of Australia's most recognisable bird species, according to researchers at The Australian National University (ANU).
Believing in climate change doesn't mean you are preparing for climate change, study finds
Notre Dame researchers found that although coastal homeowners may perceive a worsening of climate change-related hazards, these attitudes are largely unrelated to a homeowner's expectations of actual home damage.
Older forests resist change -- climate change, that is
Older forests in eastern North America are less vulnerable to climate change than younger forests, particularly for carbon storage, timber production, and biodiversity, new research finds.
Could climate change cause infertility?
A number of plant and animal species could find it increasingly difficult to reproduce if climate change worsens and global temperatures become more extreme -- a stark warning highlighted by new scientific research.
Predicting climate change
Thomas Crowther, ETH Zurich identifies long-disappeared forests available for restoration across the world.
Historical climate important for soil responses to future climate change
Researchers at Lund University in Sweden, in collaboration with colleagues from the University of Amsterdam, examined how 18 years of drought affect the billions of vital bacteria that are hidden in the soil beneath our feet.
Can forests save us from climate change?
Additional climate benefits through sustainable forest management will be modest and local rather than global.
From crystals to climate: 'Gold standard' timeline links flood basalts to climate change
Princeton geologists used tiny zircon crystals found in volcanic ash to rewrite the timeline for the eruptions of the Columbia River flood basalts, a series of massive lava flows that coincided with an ancient global warming period 16 million years ago.
Think pink for a better view of climate change
A new study says pink noise may be the key to separating out natural climate variability from climate change that is influenced by human activity.
Climate taxes on agriculture could lead to more food insecurity than climate change itself
New IIASA-led research has found that a single climate mitigation scheme applied to all sectors, such as a global carbon tax, could have a serious impact on agriculture and result in far more widespread hunger and food insecurity than the direct impacts of climate change.
More Climate Change News and Climate Change Current Events

Top Science Podcasts

We have hand picked the top science podcasts of 2019.
Now Playing: TED Radio Hour

Risk
Why do we revere risk-takers, even when their actions terrify us? Why are some better at taking risks than others? This hour, TED speakers explore the alluring, dangerous, and calculated sides of risk. Guests include professional rock climber Alex Honnold, economist Mariana Mazzucato, psychology researcher Kashfia Rahman, structural engineer and bridge designer Ian Firth, and risk intelligence expert Dylan Evans.
Now Playing: Science for the People

#540 Specialize? Or Generalize?
Ever been called a "jack of all trades, master of none"? The world loves to elevate specialists, people who drill deep into a single topic. Those people are great. But there's a place for generalists too, argues David Epstein. Jacks of all trades are often more successful than specialists. And he's got science to back it up. We talk with Epstein about his latest book, "Range: Why Generalists Triumph in a Specialized World".
Now Playing: Radiolab

Dolly Parton's America: Neon Moss
Today on Radiolab, we're bringing you the fourth episode of Jad's special series, Dolly Parton's America. In this episode, Jad goes back up the mountain to visit Dolly's actual Tennessee mountain home, where she tells stories about her first trips out of the holler. Back on the mountaintop, standing under the rain by the Little Pigeon River, the trip triggers memories of Jad's first visit to his father's childhood home, and opens the gateway to dizzying stories of music and migration. Support Radiolab today at Radiolab.org/donate.