Antarctica’s Pine Island Ice Shelf is more vulnerable than previously thought – and could cause sea levels to rise by 1.6 FEET if it collapses, study warns
- The Pine Island Ice Shelf holds enough ice to raise sea levels by 1.6 feet
- It may be more vulnerable to complete disintegration than previously thought
- In a warming climate, calving is likely to become more frequent
- Experts hope the study will further signal the urgent need to cut carbon emissions and mitigate the worst effects of climate change
Measuring roughly the same size as England, Antarctica’s Pine Island Glacier is one of the largest and fastest-moving glaciers in the world.
The glacier is responsible for about 25% of Antarctica’s ice loss, equivalent to the amount of water in 13,000 Olympic swimming pools.
But a new study has warned that the Pine Island Ice Shelf – the ice shelf that controls the flow of ice from the Pine Island Glacier – may be more vulnerable to complete disintegration than previously thought. .
Worryingly, experts from the British Antarctic Survey (BAS) say its collapse could cause global sea levels to rise by a whopping 1.6 feet (0.5 metres).
A new study has warned that the Pine Island Ice Shelf – the ice shelf that controls the flow of ice from the Pine Island Glacier – may be more vulnerable to complete disintegration than previously thought.
Pine Island Glacier
The Pine Island Ice Shelf controls the flow of ice from the Pine Island Glacier – roughly the size of England – into the Amundsen Sea.
This is a crucial role because the glacier is one of the largest and fastest in the world.
It is also responsible for about 25% of Antarctica’s ice loss.
This is equivalent to the amount of water in 13,000 Olympic swimming pools.
Previous studies have shown that the Pine Island Ice Shelf is becoming increasingly fragile due to two key processes.
First, sea ice is experiencing increased thinning due to an increase in the amount of ice melting into the sea.
Meanwhile, calving events have also increased in recent years, during which masses of ice break up into icebergs.
Now, in a new study, researchers from BAS have shown that the combination of calving and melting will likely cause it to disintegrate faster than previously thought.
“This study highlights the extreme sensitivity of ice shelves to climate change,” said Dr. Alex Bradley, ocean modeler at BAS and lead author of the study.
“This shows that the interaction between calving and melting can promote the disintegration of the Pine Island Ice Shelf, which we thought was already vulnerable to collapse.”
To reach this conclusion, the team used advanced ocean modeling techniques to simulate the effects of continuous calving events.
The graph shows how the ice front of the Pine Island Glacier ice front retreated from 2009 to 2020
Previous studies have shown that the Pine Island Ice Shelf is becoming increasingly fragile due to two key processes
Their simulations showed that calving events could lead to further thinning of the ice shelf, which in turn will make the ice shelf more vulnerable to calving.
This suggests that a feedback loop between the two processes could exist and accelerate the total collapse of the sea ice.
This would reduce the ice shelf’s ability to stem the flow of ice from the Pine Island Glacier into the sea and increase its contribution to global sea level rise.
“The complete disintegration of the Pine Island Ice Shelf will have profound consequences not only for the Pine Island Glacier, but for all of West Antarctica, as it is believed to play a vital role in maintaining stability. of the West Antarctic Ice Sheet,” explained Dr Bradley.
In a warming climate, calving is likely to become more frequent, experts warn.
They hope the new study will further signal the urgent need to reduce carbon emissions and mitigate the worst effects of climate change.
Pine Island Glacier isn’t the only one at risk of collapsing – earlier this month a study warned that Antarctica’s Thwaites Glacier is “also holding on by its nails”.
BAS researchers have found that the glacier – which is widely known as the Doomsday Glacier – has retreated twice as fast as previously thought in the past 200 years.
For the first time, scientists have mapped a critical area of the seabed in front of Thwaites in high resolution, giving them an idea of how fast the glacier has retreated and moved in the past.
The stunning images show geological features new to science and also provide a kind of crystal ball to see Thwaites’ future.
Alarmingly, analysis of the new images indicates that Thwaites’ rate of recoil that scientists have documented more recently is small compared to the fastest rates of change in its past.
THE MELTING OF GLACIERS AND ICE SHEET WOULD HAVE A “SPECTACULAR IMPACT” ON THE GLOBAL SEA LEVEL
Global sea levels could rise by up to 10 feet (3 meters) if the Thwaites Glacier in West Antarctica collapses.
Sea level rise threatens cities from Shanghai to London, low-lying areas from Florida to Bangladesh, and entire nations like the Maldives.
In the UK, for example, an elevation of 6.7 feet (2 meters) or more can cause areas such as Hull, Peterborough, Portsmouth and parts of East London and the Estuary of the Thames are in danger of being submerged.
The glacier’s collapse, which could begin decades from now, could also overwhelm major cities like New York and Sydney.
Parts of New Orleans, Houston and Miami in the southern United States would also be particularly affected.
A 2014 study by the Union of Concerned Scientists looked at 52 sea level indicators in communities across the United States.
It found that tidal flooding will increase significantly in many locations on the East Coast and Gulf Coast, based on a conservative estimate of projected sea level rises based on current data.
The results showed that most of these communities will experience a sharp increase in the number and severity of tidal floods over the next few decades.
By 2030, more than half of the 52 communities studied are expected to experience, on average, at least 24 tidal floods per year in exposed areas, assuming projections of moderate sea level rise. Twenty of these communities could see a tripling or more of tidal flooding.
The Mid-Atlantic coast is expected to see some of the largest increases in flood frequency. Places like Annapolis, Maryland and Washington, DC can expect more than 150 tidal floods per year, and several locations in New Jersey could see 80 or more tidal floods.
In the UK, a rise of two meters (6.5ft) by 2040 would see large parts of Kent almost completely submerged, according to findings from a paper published in Proceedings of the National Academy of Science in November 2016.
Areas on the south coast such as Portsmouth, as well as Cambridge and Peterborough would also be heavily affected.
Towns and villages around the Humber Estuary, such as Hull, Scunthorpe and Grimsby would also experience intense flooding.