Could ‘The Day After Tomorrow’ happen?
A collapse of the enormous ocean currents that circulate warm water around Atlantic could cool the planet so much that it would obliterate global warming for up to 20 years.
Researchers using climate modelling to study the impact of the scenario featured in the 2004 disaster movie The Day After Tomorrow.
In the film global warming causes the Atlantic Meridional Overturning Circulation (AMOC), which includes the Gulf Stream, to abruptly collapse, leading to the onset of a new Ice Age.
Now scientists have examined what would really happen should the AMOC stop working.
Recently climate scientist warned the currents in the North Atlantic appear to be slowing down at a rate never seen before, possibly due to cold fresh water from the melting Greenland ice cap.
In the latest study, Professor Sybren Drijfhout from the University of Southampton, found that if these currents did stop, the Earth would cool for around 20 years. However, he calculated it would only result in a maximum of 0.7°C (1.3°F) of cooling after about 11 years before temperatures begin to rise again.
This is unlikely to be enough to bring the widespread freezing of the Northern Hemisphere as shown in the Hollywood film. The Little Ice Age which brought colder winters to parts of Europe and North America between the sixteenth and nineteenth centuries for example, dropped by a similar amount.
Professor Drijfhout found that after 20 years temperatures caught up to modern levels and then global warming continued unabated at the rates predicted under current scenarios but were offset by about 0.8°C (1.4°F). However, some areas to the east of the North Atlantic, which rely up on the warm water brought north by the Gulf Stream for their mild climate, take longer to recover. He said: ‘The planet Earth recovers from the AMOC collapse in about 40 years when global warming continues at present-day rates.
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