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 reality.
That’s because new research warns that the Atlantic Ocean current that drives the Gulf Stream could collapse “any time” from 2025 thanks to climate change.
Formally known as the Atlantic Meridional Overturning Circulation (AMOC), the current is the driving force that brings warm water from the Gulf of Mexico to the UK and is responsible for mild winters in Western Europe.
However, if it were to collapse, the impact would be devastating.
Europe would be plunged into a deep freeze, while most of Africa, the Caribbean, and South American countries like Colombia, Peru, and Bolivia would experience dizzying temperatures.
Fears: New research warns that the Atlantic Ocean current that powers the Gulf Stream (pictured) could collapse ‘any time’ from 2025 thanks to climate change
WHAT IS 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 Atlantic to the north, and cooler fresh water in the deep Atlantic to the south.
This ocean circulation system transports a substantial amount of heat from the tropics and southern hemisphere to the North Atlantic, where the heat is transferred to the atmosphere.
High levels of carbon dioxide would cause ice melting in the Arctic and Greenland, increasing the amount of freshwater runoff into the ocean.
This increase in fresh water would disrupt the AMOC, which depends on a balance between fresh and salt water.
Scientists at the University of Copenhagen say such a scenario is ’95 percent certain’ by the end of this century if current greenhouse gas emissions persist.
Without significant action to address climate change, it would most likely happen in 2057, the experts added, although there is a chance that the collapse could occur as early as two years from now.
Ocean currents play a vital role in Earth’s climate today because they redistribute heat, cold, and rain between the tropics and the northernmost parts of the Atlantic region.
“Closing the AMOC can have very serious consequences for Earth’s climate, for example by changing the way heat and precipitation are distributed globally,” said Professor Peter Ditlevsen, from the Niels Bohr Institute at the University of Copenhagen.
“While a cooling of Europe may appear less severe as the world as a whole gets warmer and heat waves occur more frequently, this lockdown will contribute to further warming of the tropics, where rising temperatures have already led 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 past 150 years and combined it with innovative new statistical tools to reach their conclusion.
However, he takes issue with the latest report from the UN’s Intergovernmental Panel on Climate Change (IPCC), which cited climate model simulations that suggested such a change in the AMOC was highly unlikely this century.
The Danish researchers’ prediction is based on tracking early warning signs showing ocean currents as they become unstable.
Although these have been reported before, experts say that only now has the development of advanced statistical methods made it possible to predict when a collapse will occur.
Analysis: The researchers used ocean temperature data from the past 150 years and combined it with innovative new statistical tools to reach their conclusion.
Sci-fi: 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 analyzed sea surface temperatures in a specific area of the North Atlantic from 1870 to the present.
They referred to these as “fingerprints” which give an indication of the strength of the AMOC, or thermohaline circulation, which has only been correctly measured for the last 15 years.
“Using new and improved statistical tools, we have performed calculations that provide a more robust estimate of when a collapse of the thermohaline circulation is most likely to occur, something we have not been able to do before,” said Professor Susanne Ditlevsen, from the University of Copenhagen.
Until the 1800s, the AMOC was relatively stable. However, the current subsided after the so-called ‘Little Ice Age’ ended in 1850.
This caused temperatures to drop so low that the River Thames froze over, allowing Londoners to cross the channel on foot.
The last complete closure of the AMOC is thought to have occurred at the end of the last Ice Age proper, around 12,000 years ago, when temperatures in western Europe plummeted by as much as 10°C.
The new research has been published in the journal nature communications.
What would the world be like if the Gulf Stream collapsed?
If the AMOC were to collapse, much less heat would reach western Europe and the region would be plunged into very severe winters, the kind of scenario depicted in extreme fashion in the film The Day After Tomorrow.
Until the 1800s, it was relatively stable, but the current subsided after the so-called “Little Ice Age” ended in 1850.
Temperatures dropped so low that the River Thames froze over and records show Londoners crossing the canal on foot.
The last closure was probably at the end of the last Ice Age, 12,000 years ago, and caused 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 heat waves would likely become more common.
Sea levels could rise by as much as 20 inches around the North Atlantic Basin, which encircles the US East Coast.
This would eventually push people living along the coast inland to escape the flooding. There would be a widespread collapse of deep-sea ecosystems.
In the US, Florida would be particularly affected as the northward flow of water would stall and pool on the state’s coast.
A study published last year he looked at how the termination of the AMOC may affect the UK specifically.
The Little Ice Age, a centuries-long cold period that lasted until about 1850. Experts believe that when the North Atlantic began to warm near the end of the Little Ice Age, fresh water disrupted the system. Pictured, Thames Frost Fair, 1683-1684, by Thomas Wyke
Researchers at the University of Exeter created a computer model and found that by 2080 the climate would be 3.4°C colder than last year.
Rainfall during the growing season is expected to decrease by 123mm, they added.
This, Ars Technica It is reportedly enough to reduce the UK’s arable land from 32 per cent to just seven per cent, greatly affecting food production.
The effects would not be felt 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.