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Paul Dorian of the excellent weather science site Vencore Weather here brings us up to date on the latest on one of the most powerful natural cycles driving our North Atlantic climate: North Atlantic sea surface temperature (SST) cycles.

Here I’ll sum up the main points. Of course do read the entire post at Vencore for all the details.

In a nutshell the sites writes that the North Atlantic “is now showing signs of a possible long-term shift back to colder-than-normal sea surface temperatures (SST) and this could have serious implications on US climate and sea ice areal extent in the Northern Hemisphere”.

Vencore supplies the following chart of North Atlantic heat content (0 – 700 meters deep):

Global monthly heat content anomaly (GJ/m2) in the uppermost 700 m of the North Atlantic since January 1955. The thick line represents the simple running 37-month (c. 3 year) average. Data source: National Oceanographic Data Center (NODC), climate4you.com. Last period shown: October-December 2015.

The next chart Vencore provides below is one of Atlantic sea surface temperature (SST) since the 1870s.

Clearly we see that huge climate driver has been cyclic and that the past 20 years have been marked by very warm SSTs.

Observed AMO index, filtered annual mean area-averaged SST anomalies over the North Atlantic basin (0N-65N, 80W-0E), using HadISST dataset (Rayner, et al., 2003) for the period 1870-2015.; courtesy NCAR: climatedataguide.ucar.edu/climate-data/-amo.

Little wonder the North Atlantic region has been seen warmer than normal conditions over the past 2 decades.

But that warmth appears to be waning as the North Atlantic is now heading toward its cool phase. That cooling down is confirmed by the Japan Agency for Marine-Earth Science and Technology (JAMSTEC). Note how the transitions take place quickly, in a matter of just a few years.

Serious impacts on sea ice and winters

Vencore writes that the North Atlantic cooling is likely going to have some “significant impacts on Northern Hemisphere (NH) sea ice areal extent over the coming decades“, and thus could be a major blow to climate science forecasts of a melting Arctic. If the North Atlantic cooling continues, then Vencore warns we should expect Arctic sea ice to return to 1990s levels, if not even greater.

The cooling North Atlantic will also have serious ramifications for North America’s climate. Vencore reports that winters over large parts of North America are much colder during cool North Atlantic phases, and significantly warmer during the warm phases. So if these trends should continue, it means that the days of the global warming scare are numbered, or they will have to move to the other hemisphere.