In the last month, there’s been much attention to a cool patch in the North Atlantic Ocean, where record cold temperatures over the past eight months present a stark contrast to a globe that is experiencing record warmth. And although there is certainly no consensus on the matter yet, some scientists think this pattern may be a sign of long-feared consequences of climate change — a slowing of North Atlantic ocean circulation, due to a freshening of surface waters.
The cause, goes the thinking, would be the rapidly melting Greenland ice sheet, whose large freshwater flows may weaken ocean “overturning” by reducing the density of cold surface waters (colder, salty water is denser). If cold, salty waters don’t sink in the North Atlantic and flow back southward toward Antarctica at depth, then warm surface waters won’t flow northward to take their place.
Now, two new studies just out in Nature Geoscience help to underscore why scientists have a good reason to think this sort of thing can happen — namely, because it appears to have happened in the Earth’s distant past. And not just once but on multiple occasions.
Back in 2007, I posted this sun spot research that predicted that by 2020 we would be cooled by a low solar activity ( a cooler sun) period. http://terryorisms.com/2007/06/23/read-the-sunspots/