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Greenland could warm by 15 DEGREES ‘within a decade’ as experts warn over ‘abrupt and massive’ climate shift

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Greenland could warm by 15 DEGREES ‘within a decade’ as experts warn over ‘abrupt and massive’ climate shift

Category : Environment , Science , Tech

GREENLAND’S temperature could skyrocket by 15 degrees over the course of just 10 years, scientists have warned.
The change would be “abrupt and massive” – and has already happened several times during Earth’s history.
Greenland’s temperature is at risk of massively shifting in a very short space of timeGetty – Contributor
This infographic shows how Antarctica can take a long time to respond to changes in the Atlantic’s current – but are felt almost immediately in GreenlandOliver Day, Oregon State University
It’s the latest piece of research documenting the threat of significant climate change on Earth.
The study, published in Nature, details “extremely abrupt” climate change events that have taken place within the last 60,000 years.
This rapid warming of Greenland is believed to have been caused by the “strengthening and weakening” of AMOC – Atlantic Meridional Overturning Circulation.
AMOC is an oceanic current that heats up Greenland and Europe, moving warm water from the tropics into the North Atlantic Ocean.
New research links Greenland to Antarctica, mapping how changes in the northern nation affect its icy southern sisterGetty – Contributor
Here’s a freshly drilled segment of ice core that’s just been brought to the surfaceTommy Cox
The research shows how the North Atlantic ocean “communicates” these extreme events to Antarctica – which is on the opposite side of the world.
It turns out that Greenland’s very sudden temperature changes are communicated extremely slowly to Antarctica.
This abrupt warming of Greenland eventually causes Antarctica to cool down, but it takes about 200 years to take effect.
“The North Atlantic is sending messages to Antarctica on two different time scales,” said Christo Buizert, a climate change specialist at Oregon State University and lead author on the study.
“The atmospheric connection is like a text message that arrives right away, while the oceanic one is more like a postcard that takes its time getting there.
“In this case, 200 years, which makes the postal service look pretty good by comparison.”
He said that when the North Atlantic warms up because of a stronger AMOC, the whole of Antarctica “eventually will cool because of oceanic changes”.
“It begins with the winds, but the ocean delivers a much bigger impact two centuries later,” Buizert explained.
This effect means that when Greenland’s temperature suddenly spikes, it causes Antarctica’s climate to change – twice.
The first is a more immediate effect, where winds blowing around Antarctica moved away from land, causing warming.
But then there’s a later cooling effect that takes two centuries to appear.
It explains why the climate in Greenland and Antarctica haven’t always been aligned over time.
“This is the first time that you can so clearly see the nuts and bolts of how the climate works on time scales much longer than our meteorological observations,” said Justin Wettstein, a co-author and an Oregon State atmospheric scientist.
“It allows us to see how Greenland and Antarctica have been connected – spatially and temporally – long before people were running around with thermometers to measure the temperature.”
You can clearly see a layer of volcanic ash in this ice core – this can be used as a marker to help users “sync up” other ice cores from around AntarcticaHeidi Roop
The ice cores were collected at five locations across AntarcticaGetty – Contributor
Researchers documented the change by examining ice cores from across Antarctica.
By analysing water isotopes in the cores, scientists are able to work out changes in temperature.
This was then matched to dates of major climate events in Greenland, allowing links to be made.
These “abrupt” events have happened around 25 times during the last ice age, according to experts.
“When the Gulf Stream switches on to full strength, Greenland can warm as much as 10 to 15 degrees Celcius within a decade,” said Buizert.
“The change is abrupt and massive. As the ocean transfers heat to the north, the rest of the global ocean starts to cool down. Antarctica eventually ‘notices’ the oceans getting colder, but only after 200 years have passed.”
He continued: “What is really neat is that by looking at modern-day observational data we can find an analogue for what happened in the past.
“Like forensic detectives, we can compare the temperature fingerprint in the ice cores to the fingerprints of modern-day wind patterns.
“This is how we identified the culprit – the southern hemisphere westerly winds.”

Thursday January 01, 1970

Can this research help us predict the FUTURE?

Thursday January 01, 1970

Here's what you need to know…

Thursday January 01, 1970

Scientists can use this past as a guide for what will happen in the future.
Right now, the AMOC is weakening, which is expected to reduce rainfall across Asia – potentially damaging the local economy.
But changing wind patterns in the southern hemisphere also mean the ocean could struggle to collect carbon dioxide.
This means more carbon dioxide stays in the atmosphere, strengthening the greenhouse effect, and warming the planet as a result.
“We know that our world is now arming on average, but the regional changes depend also on how the atmospheric and oceanic circulations respond,” said Wettstein.
“And that is something that climate models still disagree on.
“This study gives us a real-world example of past circulation change that we can use to test and improve our models.”
It’s not just the AMOC that affects our climate, however.
Rising temperatures from greenhouse gases make a huge difference, and Antarctica’s climate is significantly affected by wind patterns and changes to the ozone layer.


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Buizert said this latest research is “really exciting for climate geeks like us to figure out how the pieces of our climate are connected”.
“The findings also may have implications for the future,” he explained.
“The AMOC is weakening now because of global warming and meltwater from Greenland.
“The ‘text message’ is being sent and atmospheric conditions are changing. The ‘postcard’ is on the way.”
Do you think humanity will win out over climate change, or are we doomed? Let us know in the comments!

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