Antarctica's ice loss helps offset global warming

A A A

Global warming has been blamed for the alarming loss of ice shelves in Antarctica, but a new study says newly-exposed areas of sea are now soaking up some of the carbon gas that causes the problem.

Scientists led by Lloyd Peck of the British Antarctic Survey (BAS) said that atmospheric and ocean carbon is being gobbled up by microscopic marine plants called phytoplankton, which float near the surface.

After absorbing the carbon through the natural process of photosynthesis, the phytoplankton are eaten, or otherwise die and sink to the ocean floor.

The phenomenon, known as a carbon sink, has been spotted in areas of open water exposed by the recent, rapid melting of several ice shelves - vast floating plaques of ice attached to the shore of the Antarctic peninsula.

Over the last 50 years, around 24,000 square kilometres (9,200 square miles) of new open water have been created this way, and swathes of it are now colonised by phytoplankton, Peck's team reports in a specialist journal, Global Change Biology.

Their estimate, based on images of green algal blooms, is that the phytoplankton absorbs 3.5 million tonnes of carbon, equivalent to 12.8 million tonnes of carbon dioxide (CO2), the principal greenhouse gas.

To put it in perspective, this is equivalent to the CO2-storing capacity of between 6,000 and 17,000 hectares (15,000 and 42,500 acres) of tropical rainforest, according to the paper.

The tally is minute compared to the quantities of greenhouse gases from fossil fuels and deforestation, which amounted to 8.7 billion tonnes of carbon in 2007.

But, said Peck, "it is nevertheless an important discovery. It shows nature's ability to thrive in the face of adversity.

"We need to factor this natural carbon absorption into our calculations and models to predict future climate change," he said in a BAS press release.

"So far, we don't know if we will see more events like this around the rest of Antarctica's coast, but it's something we'll be keeping an eye on."

The Antarctic peninsula - the tongue of land that juts up towards South America - has been hit by greater warming than almost any other region on Earth.

In the past 50 years, temperatures there have risen by 2.5 degrees Celsius (4.5 degrees Fahrenheit), around six times the global average.

Ice shelves are ledges of thick ice that float on the sea and are attached to the land. They are formed when ice is exuded from glaciers on the land.

In the past 20 years, Antarctica has lost seven ice shelves.

The process is marked by shrinkage and the breakaway of increasingly bigger chunks before the remainder of the shelf snaps away from the coast.

It then disintegrates into debris or into icebergs that eventually melt as they drift northwards.

The Antarctic ice shelves do not add to sea levels when they melt. Like the Arctic ice cap, they float on the sea and thus displace their own volume.

Ice that runs from land into the sea does add, though, to the ocean's volume, which is why some scientists are concerned for the future of the massive icesheets covering Antarctica and Greenland.

Latest stories from i100
Have you tried new the Independent Digital Edition apps?
iJobs Job Widget
iJobs General

Ashdown Group: Senior Systems Administrator - London - £50,000

£40000 - £50000 per annum + benefits: Ashdown Group: Senior Systems Administra...

Recruitment Genius: .NET Web Developer

£35000 - £45000 per annum: Recruitment Genius: A fantastic opportunity for a t...

Recruitment Genius: Customer Service Advisor

£14616 per annum: Recruitment Genius: This leading specialist in Electronic Ci...

Recruitment Genius: Pre-Press / Mac Operator / Artworker - Digital & Litho Print

Negotiable: Recruitment Genius: With year on year growth and a reputation for ...

Day In a Page

The difference between America and Israel? There isn’t one

The difference between America and Israel? There isn’t one

Netanyahu knows he can get away with anything in America, says Robert Fisk
Families clubbing together to build their own affordable accommodation

Do It Yourself approach to securing a new house

Community land trusts marking a new trend for taking the initiative away from developers
Head of WWF UK: We didn’t send Cameron to the Arctic to see green ideas freeze

David Nussbaum: We didn’t send Cameron to the Arctic to see green ideas freeze

The head of WWF UK remains sanguine despite the Government’s failure to live up to its pledges on the environment
Author Kazuo Ishiguro on being inspired by shoot-outs and samurai

Author Kazuo Ishiguro on being inspired by shoot-outs and samurai

Set in a mythologised 5th-century Britain, ‘The Buried Giant’ is a strange beast
With money, corruption and drugs, this monk fears Buddhism in Thailand is a ‘poisoned fruit’

Money, corruption and drugs

The monk who fears Buddhism in Thailand is a ‘poisoned fruit’
America's first slavery museum established at Django Unchained plantation - 150 years after slavery outlawed

150 years after it was outlawed...

... America's first slavery museum is established in Louisiana
Kelly Clarkson: How I snubbed Simon Cowell and become a Grammy-winning superstar

Kelly Clarkson: How I snubbed Simon Cowell and become a Grammy-winning superstar

The first 'American Idol' winner on how she manages to remain her own woman – Jane Austen fascination and all
Tony Oursler on exploring our uneasy relationship with technology with his new show

You won't believe your eyes

Tony Oursler's new show explores our uneasy relationship with technology. He's one of a growing number of artists with that preoccupation
Ian Herbert: Peter Moores must go. He should never have been brought back to fail again

Moores must go. He should never have been brought back to fail again

The England coach leaves players to find solutions - which makes you wonder where he adds value, says Ian Herbert
War with Isis: Fears that the looming battle for Mosul will unleash 'a million refugees'

The battle for Mosul will unleash 'a million refugees'

Aid agencies prepare for vast exodus following planned Iraqi offensive against the Isis-held city, reports Patrick Cockburn
Yvette Cooper: We can't lose the election. There's too much on the line

Yvette Cooper: We can't lose the election. There's too much on the line

The shadow Home Secretary on fighting radical Islam, protecting children, and why anyone in Labour who's thinking beyond May must 'sort themselves out'
A bad week for the Greens: Leader Natalie Bennett's 'car crash' radio interview is followed by Brighton council's failure to set a budget due to infighting

It's not easy being Green

After a bad week in which its leader had a public meltdown and its only city council couldn't agree on a budget vote, what next for the alternative party? It's over to Caroline Lucas to find out
Gorillas nearly missed: BBC producers didn't want to broadcast Sir David Attenborough's famed Rwandan encounter

Gorillas nearly missed

BBC producers didn't want to broadcast Sir David Attenborough's famed Rwandan encounter
Downton Abbey effect sees impoverished Italian nobles inspired to open their doors to paying guests for up to €650 a night

The Downton Abbey effect

Impoverished Italian nobles are opening their doors to paying guests, inspired by the TV drama
China's wild panda numbers have increased by 17% since 2003, new census reveals

China's wild panda numbers on the up

New census reveals 17% since 2003