I have no proof but it looks like the El Nino (EN) and the PDO have somewhat complementary effects on climate.
EN seems to correlate with sudden increases in tropospheric temperatures, which then plunge into the opposite direction when the subsequent La Ninas occur.
Usually the EN and the spikes of the PDO don’t coincide, but when they do it would cause a global change in Earth’s climate- either a step change or not, but a clear change in the “derivative” of the graph of the average temperatures.
This happened in 1982-83 when Earth’s temperatures started to increase fast and was one of the main fuels of the AGW propaganda (to a certain extent AGW looked a reasonable hypothesis at that time and fooled many, me included). It also happened with the strong EN of 1997-98 which coincided with a strong warming of the Pacific.
I’m considering the following data for EN,
and the graph above of “climate4you” for the PDO since 1979.
In 1992-93 there was another spike of the PDO but no strong EN, and the relatively strong EN of 2009-10 had no correspondent sudden increase of the PDO, and in both cases the tropospheric temperatures didn’t change their general trend (“derivative”).
Now, we’re having the great warming of the PDO of the last 1 + 1/2 years coinciding with EN conditions.
I think this indicates that the direction of Earth’s temperatures is about to change again.
I believe it’s toward a cooling period, similar but opposite to the warming phase of the last 2 decades of the XX century.
The following graph
shows an obvious step change, and a totally different “picture” than the one usually presented in the climate debate.
On the other hand, if we extend the first period up to 1997 and jump the ENSO of 1998-2001, we get two periods of opposite linear trends instead
The 1st graph reminds me of the 2 step-changes that happened at the tropopause in the same period
and similar also to the step-like decreases– in 1986 and 1998– in atmospheric humidity at 9 km altitude (300 mb)
As a possible explanation, I believe these step changes are related with the rapid excursion of the magnetic N. Pole since the 1980’s,
Note how the excursion also seems to have two “step changes” of speed, again at the beginning of the 1980’s and the end of the 1990’s.
Now, if we think that:
/1/ The beginning of the 1980’s coincides with the maximum of cycle #21– which is considered by some researchers (like Lockwood et at. in the paper “Centennial variations in sunspot number, open solar flux, and streamer belt width: 2. Comparison with the geomagnetic data”
as the highest point of the grand solar maximum of the XX century,
as indicated by the following figure,
/2/ “According to Professor Mike Lockwood the late 20th century was a period when the sun was unusually active and a so called ‘grand maximum’ occurred around 1985.
Since then the sun has been getting quieter.
By looking back at certain isotopes in ice cores, he has been able to determine how active the sun has been over thousands of years.
Following analysis of the data, Professor Lockwood believes solar activity is now falling more rapidly than at any time in the last 10,000 years.“
/3/ An important change happened in the Sun at the mid-to-end of the 1990’s– i.e., the beginning of solar cycle #23– when the solar magnetic polar fields started to behave in an “unusual way”, possibly indicating the beginning of a new grand minimum,
Then, a pattern seems to emerge, and it is related with the main forces at play in this scenario, which are, in my opinion, the solar radiations and Earth’s magnetic field.
This pattern could be indicating that Earth’s climate is nearing or is at the point of a new glacial inception, i. e., the end of the present Interglacial.