The real-life Day After Tomorrow: The Gulf Stream
could COLLAPSE at 'any time' from 2025 thanks to climate change – plunging
Europe into a deep freeze, warn scientists
The current is known formally as the Atlantic
Meridional Overturning Circulation
Its collapse was featured in the Hollywood blockbuster
'The Day After Tomorrow'
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By SAM
TONKIN FOR MAILONLINE
UPDATED:
07:47, 26 July 2023
In the
Hollywood blockbuster 'The Day After Tomorrow', ocean currents around the world
stop as a result of global warming, triggering a new Ice Age on Earth.
That may
have been science fiction but scientists say the terrifying prophecy could soon
become a reality.
That's
because new research warns that the Atlantic Ocean current which drives the
Gulf Stream could collapse at 'any time' from 2025 thanks to climate change.
Known
formally as the Atlantic Meridional Overturning Circulation (AMOC), the current
is the driving force which brings warm water from the Gulf of Mexico up to the
UK and is responsible for mild winters in Western Europe.
If it
collapsed, however, the impact would be devastating.
Europe
would be plunged into a deep freeze, while most of Africa, the Caribbean, and
South American countries such as Colombia, Peru and Bolivia would experience
rocketing temperatures.
Fears: New research warns that the Atlantic Ocean
current which drives the Gulf Stream could collapse at 'any time' from 2025
thanks to climate change
WHAT IS THE
AMOC?
The
Atlantic Meridional Overturning Circulation (AMOC) is an important component of
the Earth’s climate system.
The pattern
carries warm, salty water in the upper layers of the Atlantic northward, and
colder fresh water in the deep Atlantic southward.
This ocean
circulation system transports a substantial amount of heat from the Tropics and
Southern Hemisphere toward the North Atlantic, where the heat is transferred to
the atmosphere.
High levels
in carbon dioxide would cause Arctic and Greenland ice melt, increasing the
amount of freshwater run-off into the ocean.
This
increase in freshwater would dirupt the AMOC, which relies on a balance between
fresh and salt water.
Scientists
at the University of Copenhagen say such a scenario is '95 per cent certain' by
the end of this century if current greenhouse gas emissions persist.
More likely
is that without significant action to tackle climate change it will happen in
2057, the experts added, although there is a chance the collapse could come as
early as two years' time.
The ocean
currents play a vital role in Earth's current climate because they redistribute
heat, cold and rainfall between the tropics and the northernmost parts of the
Atlantic region.
'Shutting
down the AMOC can have very serious consequences for Earth's climate, for
example, by changing how heat and precipitation are distributed globally,' said
Professor Peter Ditlevsen, from the University of Copenhagen's Niels Bohr
Institute.
'While a
cooling of Europe may seem less severe as the globe as a whole becomes warmer
and heat waves occur more frequently, this shutdown will contribute to an
increased warming of the tropics, where rising temperatures have already given
rise to challenging living conditions.'
He added:
'Our result underscores the importance of reducing global greenhouse gas
emissions as soon as possible.'
The
researchers used ocean temperature data from the last 150 years and combined it
with innovative new statistical tools to come to their conclusion.
However, it
is at odds with the latest report by the UN's Intergovernmental Panel on
Climate Change (IPCC), which cited climate model simulations suggesting such
change to the AMOC was very unlikely this century.
The Danish
researchers' prediction is based on the monitoring of early warning signals
which ocean currents exhibit as they become unstable.
Although
these have been reported previously, the experts say only now has the
development of advanced statistical methods made it possible to predict just
when a collapse will occur.
Analysis:
The researchers used ocean temperature data from the last 150 years and
combined it with innovative new statistical tools to come to their conclusion
Analysis:
The researchers used ocean temperature data from the last 150 years and
combined it with innovative new statistical tools to come to their conclusion
Science
fiction: In the Hollywood blockbuster 'The Day After Tomorrow' (pictured),
ocean currents around the world stop as a result of global warming, triggering
a new Ice Age on Earth
Science
fiction: In the Hollywood blockbuster 'The Day After Tomorrow' (pictured),
ocean currents around the world stop as a result of global warming, triggering
a new Ice Age on Earth
The
researchers analysed sea surface temperatures in a specific area of the North
Atlantic from 1870 to today.
They
referred to these as 'fingerprints' which give an indication to the strength of
the AMOC, or Thermohaline Circulation — which has only been properly measured
for the past 15 years.
'Using new
and improved statistical tools, we've made calculations that provide a more
robust estimate of when a collapse of the Thermohaline Circulation is most
likely to occur, something we had not been able to do before,' said Professor
Susanne Ditlevsen, of the University of Copenhagen.
Until the
1800s, the AMOC was relatively stable. However, the current declined after the
so-called 'Little Ice Age' ended in 1850.
This saw
temperatures drop so low that the River Thames completely froze over, enabling
Londoners to cross the waterway on foot.
The last
total shutdown of the AMOC is believed to have occurred at the end of the last
proper Ice Age around 12,000 years ago, where temperatures in western Europe
plummeted by up to 10°C.
The new
research has been published in the journal Nature Communications.
What would
the world look like if the Gulf Stream collapsed?
If the AMOC
was to collapse, far less heat would reach western Europe and the region would
be plunged into very severe winters, the kind of scenario depicted in an
extreme fashion in the movie The Day After Tomorrow.
Until the
1800s, it was relatively stable but the current declined after the so-called
'Little Ice Age' ended in 1850.
Temperatures
dropped low enough that the River Thames completely froze over and records show
Londoners crossing the waterway on foot.
The last
shutdown was probably at the end of the last Ice Age, 12,000 years ago, and it
prompted a temperature drop of 5°C to 10°C in western Europe.
In the
event of another collapse, not only would European winters become much colder
but summer droughts, storms and heatwaves would likely become more common.
Sea levels
could rise up to nearly 20 inches around the North Atlantic Basin, which
surrounds the eastern US coast.
This would
eventually push people living along the coast further inland to escape
flooding. A widespread collapse of deep-sea eco-systems would occur.
In the US,
Florida would be particularly badly affected as the flow of water northwards
would be halted, seeing it collect on the state's shoreline.
A study
published last year looked at how the cessation of the AMOC may impact the UK
specifically.
The Little
Ice Age, a centuries-long cold period that lasted until about 1850. Experts
believe that as the North Atlantic began to warm near the end of the Little Ice
Age, freshwater disrupted the system. Pictured is Thames Frost Fair, 1683–84,
by Thomas Wyke
The Little
Ice Age, a centuries-long cold period that lasted until about 1850. Experts
believe that as the North Atlantic began to warm near the end of the Little Ice
Age, freshwater disrupted the system. Pictured is Thames Frost Fair, 1683–84,
by Thomas Wyke
University
of Exeter researchers made a computer model and found that by 2080 the weather
would be 3.4°C colder than it was last year.
Rainfall
during the growing season is expected to drop by 123mm, they added.
This, Ars
Technica reports, is enough to reduce the UK's arable land from 32 percent to
just seven percent, greatly affecting food production.
The effects
would be felt not in Europe and the United States, with forecasts also
projecting that the collapse of the AMOC would also increase drought in the
Sahel in Africa.
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