Will a crucial ocean current shut down?
The Atlantic Ocean and an Actual Debate in Climate ScienceROBINSON MEYER
JAN 7, 2017, The Atlantic
About 30 years ago, climate researchers became concerned that AMOC [Atlantic Meridional Overturning Circulation, a.k.a. the Gulf Stream] could suddenly shut down as a result of anthropogenic climate change. The “paleoclimatic record”—that is, what the planet’s geology and fossil record reveal of previous global climates—showed that the AMOC has rapidly collapsed in the past. “Rapidly” here means “within the span of a human lifetime.”
This week, the consensus on AMOC was challenged again. A team of researchers have showed in Science Advances that a popularly used climate model may significantly overestimate the stability of AMOC. Once you account for this bias, AMOC proves much more likely to collapse, they argue. And this collapse could happen without any freshwater injection from Greenland.
In other words, they show that the stress of global warming can push AMOC into collapse all by itself in at least one model. Freshwater doesn’t need to pour in from Greenland for AMOC to fall apart; simply increasing the temperature of the ocean can do it.
(The article is here.)