D'Aleo-Strong Evidence For Suns Role in the EPO/NAO/AO In Winter 10 years ago
August 12, 2011
We have noted that the sun plays a role in climate and weather in many ways. When the sun is more active near solar maxima, the sun is slightly brighter and irradiance increases - 0.1% on most recent cycles, more in cycle 23. There is also up to 10% more UV radiation which produces ozone chemistry related warming in low and middle latitudes high up in the atmosphere that works itys way down to the mid-troposhpere as shown in data by Karin Labitzke in numerous papers in recent decades and in models by Hansen's star climate modeller, Drew Shindell. Geomagnetic storms can affect high latitude patterns and blocking. Diffusion of galactal cosmic rays which play a role in low water cloudiness through ion mediated nucleation can produce less low cloudiness (the Svensmark effect).
After the hurricane season winds down, I will expand on all of these.
I ran across a slide from a paper in the Journal of Climate by CPC in an old presentation I made to the Bank of Montreal one day 8 years ago that I think is VERY CONVINCING that the sun can play a role in weather patterns.See how the strength of the high atmospheric portion of thw warm core subtropical Pacific high is extremely well correlated with the solar cycles (here solar flux which itself correlates well with ultraviolet). When the sun is active the high is pumped up, when quiet weaker.
The Pacific high plays a role in the East Pacific Oscillation which when positive leads to central North America warming and negative cooling.
The positive state is shown above, reverse colors for the negative.
I did a difference of the 500mb heights from the last solar max to the solar minimum years and definitely see the pattern flip. In other words, the EPO was positive near the solar max and negative in the solar min years 2008-2009. Notice the NAO/AO has also flipped from posiitve to negative likely at least in part in response to this upstream flip.
This in turn, explains the winter cooling, greatest in the EPO sweet spot in the north central.