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https://theconversation.com/atlantic-ocean-is-headed-for-a-tipping-point-once-melting-glaciers-shut-down-the-gulf-stream-we-would-see-extreme-climate-change-within-decades-study-shows-222834>
"Superstorms, abrupt climate shifts and New York City frozen in ice. That’s how
the blockbuster Hollywood movie “The Day After Tomorrow” depicted an abrupt
shutdown of the Atlantic Ocean’s circulation and the catastrophic consequences.
While Hollywood’s vision was over the top, the 2004 movie raised a serious
question: If global warming shuts down the Atlantic Meridional Overturning
Circulation, which is crucial for carrying heat from the tropics to the
northern latitudes, how abrupt and severe would the climate changes be?
Twenty years after the movie’s release, we know a lot more about the Atlantic
Ocean’s circulation. Instruments deployed in the ocean starting in 2004 show
that the Atlantic Ocean circulation has observably slowed over the past two
decades, possibly to its weakest state in almost a millennium. Studies also
suggest that the circulation has reached a dangerous tipping point in the past
that sent it into a precipitous, unstoppable decline, and that it could hit
that tipping point again as the planet warms and glaciers and ice sheets melt.
In a new study using the latest generation of Earth’s climate models, we
simulated the flow of fresh water until the ocean circulation reached that
tipping point.
The results showed that the circulation could fully shut down within a century
of hitting the tipping point, and that it’s headed in that direction. If that
happened, average temperatures would drop by several degrees in North America,
parts of Asia and Europe, and people would see severe and cascading
consequences around the world.
We also discovered a physics-based early warning signal that can alert the
world when the Atlantic Ocean circulation is nearing its tipping point."
Cheers,
*** Xanni ***
--
mailto:xanni@xanadu.net Andrew Pam
http://xanadu.com.au/ Chief Scientist, Xanadu
https://glasswings.com.au/ Partner, Glass Wings
https://sericyb.com.au/ Manager, Serious Cybernetics
