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> If the AMOC collapsed, it would increase cooling of the Northern Hemisphere, sea level rise in the Atlantic This seems somewhat counter productive, if the no

> If the AMOC collapsed, it would increase cooling of the Northern Hemisphere, sea level rise in the Atlantic This seems somewhat counter productive, if the northern hemesphere is cooling, how would that result with sea levels rising? Or they're not related ? This really seems strange, would a new `current` not naturally establish based on the temperature relocations ?

laurent92 5y ago
Another funny item is, icecaps attract water by gravity, so if they melt, sea would lower by ~7m around the caps, and rise around the tropics. Anyway, with so many parameters and effects, I don’t venture into predictions anymore ;)
tuatoru 5y ago
> This seems somewhat counter productive I'm guessing you mean counterintuitive. That's one of the great things about the scientific method, that it tells you things you never would have guessed. > how would that result with sea levels rising? The Gulf Stream (part of the AMOC) brings warm water north, Evaporation happens (and the evaporated water rains out over land, where some is absorbed or flows south). The remaing sea water on the surface is now saltier and denser so sinks. Without the AMOC, the surface water is less dense. The local mean sea level rises due to gravitational effects. Precipitation also happens more over the sea, freshening the surface sea water. Fresh water is most dense (compact) at 4 degrees Celsius. Salt affects this, but the less salt there is, the smaller the effect. I guess when you crunch the numbers you get the result they state. > would a new `current` not naturally establish Last I checked, some years ago, I think it was believed that no new large-scale overturning current would establish for some thousands of years, which means the sea stratifies (settles into non-mixing layers), with a top relatively fresh and light layer over dense anoxic deeps.
- bilekas 5y ago
  That's both crazy interesting and terrifying.. Thanks for clearing it up!

laurent92 5y ago

Another funny item is, icecaps attract water by gravity, so if they melt, sea would lower by ~7m around the caps, and rise around the tropics. Anyway, with so many parameters and effects, I don’t venture into predictions anymore ;)

tuatoru 5y ago

> This seems somewhat counter productive I'm guessing you mean counterintuitive. That's one of the great things about the scientific method, that it tells you things you never would have guessed. > how would that result with sea levels rising? The Gulf Stream (part of the AMOC) brings warm water north, Evaporation happens (and the evaporated water rains out over land, where some is absorbed or flows south). The remaing sea water on the surface is now saltier and denser so sinks. Without the AMOC, the surface water is less dense. The local mean sea level rises due to gravitational effects. Precipitation also happens more over the sea, freshening the surface sea water. Fresh water is most dense (compact) at 4 degrees Celsius. Salt affects this, but the less salt there is, the smaller the effect. I guess when you crunch the numbers you get the result they state. > would a new `current` not naturally establish Last I checked, some years ago, I think it was believed that no new large-scale overturning current would establish for some thousands of years, which means the sea stratifies (settles into non-mixing layers), with a top relatively fresh and light layer over dense anoxic deeps.

bilekas 5y ago
That's both crazy interesting and terrifying.. Thanks for clearing it up!