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Antarctica’s worst-case local weather state of affairs laid naked: Terrifying research reveals how ice protection may plummet by 20% by 2100 – sparking catastrophic world sea stage rise

Antarctica’s vast ice sheets and fragile ecosystems are already changing at an alarming rate – and now scientists have revealed just how bad it could get.

A terrifying new study has laid bare the frozen continent’s best and worst–case climate change scenarios.

The international team of researchers focused their predictions on the Antarctic Peninsula, a region that is particularly sensitive to human–caused climate change.

In the worst scenario, sea ice coverage around the Peninsula could plummet by 20 per cent by 2100. 

This would be devastating for polar species, such as penguins and whales, but could also cause disastrous consequences around the globe.

Like taking the ice cubes out of a cold drink, massive loss of sea ice will accelerate ocean warming, eroding the glaciers and ice shelves that threaten catastrophic sea level rise.

Lead author Professor Bevan Davies, of Newcastle University, says: ‘Changes in the Antarctic do not stay in the Antarctic.

‘Though Antarctica is far away, changes here will impact the rest of the world through changes in sea level, oceanic and atmospheric connections and circulation changes.’

These maps show the changes in sea ice coverage under a low (top), medium-high (middle), and very high (bottom) emissions scenario. The dark blue shows areas of more extreme ice loss

These maps show the changes in sea ice coverage under a low (top), medium–high (middle), and very high (bottom) emissions scenario. The dark blue shows areas of more extreme ice loss 

Scientists have laid bare Antarctica's worst-case climate scenario, as scientists predict that sea ice coverage could shrink by 20 per cent. Pictured: An area of the Antarctic Peninsula that had been covered by ice for thousands of years until 2024

Scientists have laid bare Antarctica’s worst–case climate scenario, as scientists predict that sea ice coverage could shrink by 20 per cent. Pictured: An area of the Antarctic Peninsula that had been covered by ice for thousands of years until 2024

Although the entire Antarctic continent is changing, the Antarctic Peninsula is in a unique position.

Unlike most of the continent, the Peninsula has been frequently visited by researchers, tourists, and fishers for much of the last century.

This means scientists have an extremely good picture of how the region has been affected by the warming climate.

Co–author Professor Peter Convey, of the British Antarctic Survey, says: ‘For a casual visitor, the first impression is still inevitably that the region is ice–dominated.

‘However, to those of us that have the privilege to go back multiple times, there are very clear changes over time.’

This area is also extremely important for ensuring that the global climate remains cool and stable.

The vast stretches of white ice reflect heat out into space and lock up fresh water that would otherwise increase sea levels and weaken vital ocean currents.

To understand how this sensitive region might continue to change in the future, the researchers used computer modelling to predict what would happen in low, medium–high, and very high emissions scenarios.

The researchers focused their predictions on the Antarctic Peninsula (pictured), a region that is particularly sensitive to human-caused climate change, to see how the area would change under different emissions scenarios

The researchers focused their predictions on the Antarctic Peninsula (pictured), a region that is particularly sensitive to human–caused climate change, to see how the area would change under different emissions scenarios 

Antarctica’s worst–case climate scenario

If temperatures rise by 4.4°C (7.92°F) by 2100:

  • Ice coverage will plummet by 20%, sparking 22mm of sea level rise
  • Krill will be decimated, limiting food for penguins, seals, and whales
  • Heavy rain will wipe out the Adelie penguin population

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In the low emissions scenario, global temperatures rise 1.8°C (3.24°F) above the pre–industrial average by 2100.

In the medium–high scenario, temperatures would increase by 3.6°C (6.48°F) by 2100, and the high emissions scenario will see the world get 4.4°C (7.92°F) hotter.

Co–author Professor Martin Siegert, of Exeter University, told the Daily Mail that the hottest scenario would be ‘a world very different to today, in ways our human civilisation development has not previously coped with.’

In the worst–case scenario, water temperatures in the Southern Ocean will get hotter much faster.

This will make the Antarctic’s ice shelves much more likely to collapse, dumping vast quantities of fresh water into the oceans and sparking massive sea level rise.

According to the researchers’ modelling, the Antarctic Peninsula alone could increase sea levels by up to 22 millimetres in 2100 and up to 172 millimetres in 2300.

This level of heating would also lead to a significant loss in Antarctic sea ice, which would have a significant knock–on effect.

Professor Davies told the Daily Mail: ‘This would darken the ocean, making it better at absorbing heat, amplifying global warming.’

The Antarctic Peninsula has already undergone rapid changes due to global warming. In the 1990s, the exposed black peak emerging from the glacier in the top right was a tiny rock poking through the ice that was small enough to ski over

The Antarctic Peninsula has already undergone rapid changes due to global warming. In the 1990s, the exposed black peak emerging from the glacier in the top right was a tiny rock poking through the ice that was small enough to ski over

The loss of sea ice in the worst-case scenario will lead to widespread knock-on effects, including rapid ocean warming, the collapse of global ice shelves, rapid sea level rise, and greater severity of extreme weather events

The loss of sea ice in the worst–case scenario will lead to widespread knock–on effects, including rapid ocean warming, the collapse of global ice shelves, rapid sea level rise, and greater severity of extreme weather events 

Likewise, warmer water means the oceans can store more energy, leading to more violent weather all around the globe.

Loss of sea ice this dramatic will also have a huge impact on the Antarctic ecosystem, especially on the population of krill, a small crustacean that thrives in the Peninsula.

Krill are the base of the Antarctic food chain, supporting iconic species like penguins, seals, and whales.

However, krill are entirely dependent on sea ice, so their population shrinks along with the ice.

Scientists have found that species like the Adelie penguin, which are highly dependent on sea ice and krill, have started to be replaced by more adaptable species.

As the planet warms, Antarctica will also start to see more rain, which can wipe out entire penguin breeding colonies.

‘Adelie penguin chicks cannot tolerate rain as their downy feathers are not waterproof, so if they get wet, they get hypothermia,’ Professor Davies explains.

However, the loss of krill also has serious consequences for humans because they are one of the major means by which the southern ocean absorbs and traps carbon dioxide.

Scientists have found that species like the Adelie penguin (pictured), which rely on sea ice and the krill that live there, are already vanishing from parts of the Antarctic Peninsula

Scientists have found that species like the Adelie penguin (pictured), which rely on sea ice and the krill that live there, are already vanishing from parts of the Antarctic Peninsula 

This means that a collapse of the Antarctic ecosystem could accelerate the already devastating process of global warming.

Currently, researchers estimate that the world is on track for a medium or medium–high emissions scenario.

In a medium scenario, carbon dioxide emissions flatline and then begin to fall from 2100, while the medium–high scenario is a world in which emissions double by 2100.

Professor Davies says that we are currently somewhere between these two cases, but that ‘resurging nationalism and protectionism’ threatens to push the world towards the medium–high case.

In a lower emissions scenario, the ongoing effects of climate change will continue to trigger ice loss and extreme weather, but the effects will be much more muted.

Sea ice will only be a little smaller than it is today, and the sea level rise contributions from the Antarctic Peninsula will be limited to a few millimetres.

However, the hotter the world gets, the more destructive and permanent the effects of climate change will become.

Professor Davies says: ‘These changes would be irreversible on any human timescale. It would be very hard to regrow the glaciers and bring back the wildlife that makes Antarctica special. If we don’t make changes now, our great–grandchildren will have to live with the consequences.’

SEA LEVELS COULD RISE BY UP TO 4 FEET BY THE YEAR 2300

Global sea levels could rise as much as 1.2 metres (4 feet) by 2300 even if we meet the 2015 Paris climate goals, scientists have warned.

The long-term change will be driven by a thaw of ice from Greenland to Antarctica that is set to re-draw global coastlines.

Sea level rise threatens cities from Shanghai to London, to low-lying swathes of Florida or Bangladesh, and to entire nations such as the Maldives.

It is vital that we curb emissions as soon as possible to avoid an even greater rise, a German-led team of researchers said in a new report.

By 2300, the report projected that sea levels would gain by 0.7-1.2 metres, even if almost 200 nations fully meet goals under the 2015 Paris Agreement.

Targets set by the accords include cutting greenhouse gas emissions to net zero in the second half of this century.

Ocean levels will rise inexorably because heat-trapping industrial gases already emitted will linger in the atmosphere, melting more ice, it said.

In addition, water naturally expands as it warms above four degrees Celsius (39.2°F).

Every five years of delay beyond 2020 in peaking global emissions would mean an extra 8 inches (20 centimetres) of sea level rise by 2300.

‘Sea level is often communicated as a really slow process that you can’t do much about … but the next 30 years really matter,’ said lead author Dr Matthias Mengel, of the Potsdam Institute for Climate Impact Research, in Potsdam, Germany.

None of the nearly 200 governments to sign the Paris Accords are on track to meet its pledges.