There is a cold blob in the North Atlantic. I did not make up the term, it is the moniker used by oceanographers to describer an area of water south of Greenland which is far less salty than water approaching from the Gulf Stream arriving from southwest of the blob. What should happen is the salty cold water of the area should sink, allowing the relatively warmer waters of the Gulf Stream flow. The lower density water of the “blob” doesn’t sink creating a partial road block…backing up things all the way to Africa.  If you are interested in a fascinating and approachable article on such things of the ocean, take 10 minutes or so and read this fascinating article from the New York Times.