The summary:
This “hotspot” is due to the faster turnover of water through the Atlantic’s currents as compared to the Pacific, where water can take 200-300 years to make a full circuit from one end of the Atlantic to the other, as compared to the 600-900 years it might take for water to get around the Pacific.
In this case, warm waters from the Caribbean Sea that would normally be circulated northeast across the Atlantic Ocean are instead pooling off of the U.S. East Coast, due to the interruption of the North Atlantic Current. As water warms it expands, causing the ocean level to be higher wherever this expansion is experienced. NASA currently uses this effect to track ocean temperatures via satellite, using radar to record regional sea level changes to determine their temperatures.
Another recent study has shown that this has already happened, when a 4-inch sea level rise was recorded in a region of ocean between New York and Newfoundland that occurred in 2009 and 2010, due to a sudden change in the North Atlantic current.
