🚀 go-pugleaf

About a year ago, Scientific American had a long article on exactly this
problem -- melt-water changing ocean currents -- from the long perspective.
There's interesting evidence that a little blip of global cooling, a brief
reversal to ice-age conditions, took place when Lake Agassiz (central 
North America) followed the melting ice cap far enuf north that it suddenly
found an outlet via Hudson`s Bay instead of the Mississippi. The surge of
cold fresh water appears to have shut off the gulf stream, giving Northern
Europe a much colder climate. It prevented trees from getting established
(that's one of the climate markers).

I think it was Willy Ley who noted that you can't figure out how a
locomotive works by melting it down and analyzing the mess; similarly,
you may not learn much about the oceans by assuming they are evenly mixed.