Troposphere temperatures are very closely tied to Atlantic Multidecadal Oscillation (AMO) ocean circulation. The correlation is almost perfect.
The name of this web site is realclimatescience.com, though most of the time I am discussing the mind-blowing CO2 junk science which currently pervades academia and government.
However, there are a few real scientists working on climate, and I was fortunate to have spent time with one who actually did understand how the climate worked. Dr. Bill Gray from CSU spent many hours explaining to me how ocean cycles drive the climate, and how they are driven in turn by cyclical changes in ocean salinty. Bill’s theory in a nutshell was that evaporation in the warm, sunny mid-Atlantic increases the salinity of the water there. As the salinity increases, the water becomes increasingly dense and eventually starts to dive down towards the colder sea floor – forcing colder, less saline water to the surface. This process repeats continuously, driving the AMO and other ocean currents. Bill’s success as a tropical meteorologist and hurricane forecaster was largely due to his understanding of the AMO.
The understanding that ocean circulation drives the climate goes back to 1894, when an ocean traveler wrote a book and published in Scientific American an explanation of the connections. The author did not understand the mechanisms driving the changes in circulation, but he did keenly understand that climate change was driven by changes in ocean circulation.
The author believed that changes in ocean circulation were the cause of ice ages, and NOAA still sees the connection.
Models of the ocean and atmosphere that interact with each other indicate that the AMO cycle involves changes in the south-to-north circulation and overturning of water and heat in the Atlantic Ocean. This is the same circulation that we think weakens during ice ages, but in the case of the AMO the changes in circulation are much more subtle than those of the ice ages. The warm Gulf Stream current off the east coast of the United States is part of the Atlantic overturning circulation. When the overturning circulation decreases, the North Atlantic temperatures become cooler.
After President Trump takes over in January, I hope we will see a restoration of science – and an end to the James Hansen/Al Gore driven junk science which has wrecked a generation.