Hot NH Summers & El Ninos
By Paul Homewood
There have been many reports about the hot summer just passed in much of the Northern Hemisphere. And, inevitably, it has been blamed on climate change.
However, analysis of the UAH satellite data shows a different story:
https://www.nsstc.uah.edu/data/msu/v6.0/tlt/uahncdc_lt_6.0.txt
What we see is this summer has been similar to other recent summers such as 1998, 2010 and 2016.
The significance of this is that these three years all came at the tail end of large El Ninos:
https://www.esrl.noaa.gov/psd/enso/mei/
El Ninos leave a lot of heat behind in the atmosphere, which can take a long time to dissipate. However, both the 1998 and 2010 events were quickly followed by strong La Ninas, during which temperatures returned to normal.
This however did not happen after the 2015/16 El Nino. There was only a very weak La Nina, itself bracketed to two short lived weak El Ninos. It is this fact that explains why NH temperatures have still been artificially elevated this summer.
Every action has a reaction, as they say. La Ninas are a time when the Equatorial Pacific is recharging its batteries, as it were, thus eventually setting the scene for the next El Nino. For instance, it was the La Nina of 2010/11 which made the 2015/16 El Nino so strong.
The lack of any significant La Nina since 2016 means that the next El Nino is likely also to be a weak affair.
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NOT A LOT OF PEOPLE KNOW THAT 
” However, both the 1998 and 2010 events were quickly followed by strong La Ninas, during which temperatures returned to normal”
1997 was the strong El-Nino 3.4. It was immediately followed in 1998 by the strong La-Nina. That’s when the surface heat took place after which the global temperatures began their “pause”. There was no 2010 El-Nino event.
” There was no 2010 El-Nino event.”
Don’t be silly!
The 2009/2010 El Nino began in June 2009 and lasted through to May 2010
https://www.esrl.noaa.gov/psd/enso/mei/table.html
It is well described here:
https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2011GL048521
and here:
http://www.bom.gov.au/climate/enso/history/ln-2010-12/Nino-to-Nina.shtml
Paul… I was talking about the Nino 3.4…which is the default ONI ENSO in most discussions. The three major ENSO 3.4 events were 1982-83. 1997-98 and 2015-17. The data are at HadLSSTt1.1. The MEI index is of course different. This is part of the problem in using equatorial Pacific sea surface temperatures from different sources to predict global temperatures. Either or both are natural events unaffected by human additions of CO2. That should be the bottom line.
Except that there was:
The latest El Niño event in 2009–2010, which is classified as warm pool El Niño, holds a unique ground in that it marks the strongest warming signal in the central Pacific but rapidly decays to strong La Niña
https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2011GL048521
The 2009–10 El Niño commenced in May 2009, reaching its peak in late December 2009 before breaking down in the first quarter of 2010. The Pacific Ocean returned to neutral by late April 2010, but continued to cool rapidly during autumn.
http://www.bom.gov.au/climate/enso/history/ln-2010-12/Nino-to-Nina.shtml
The moderate El Nino of the past year has officially bowed out, leaving his cool sister, La Nina, poised to potentially take the equatorial stage.
The latest image of Pacific Ocean sea surface heights from the NASA/European Ocean Surface Topography Mission/Jason-2 oceanography satellite, dated June 11, 2010, shows that the tropical Pacific has switched from warm (red) to cold (blue) during the last few months.
https://phys.org/news/2010-06-adios-el-nino-la-nina.html
Satellite observations suggest that the intensity of El Niño events in the central equatorial Pacific (CP) has almost doubled in the past three decades, with the strongest warming occurring in 2009–10
https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2010GL044007
The Rutgers Snow Lab NH snow cover data has been trending exactly on the average for over two decades.
I graphed it a few weeks ago and added a regression line to prove this.
This is the area at or below 0 C in the northern hemisphere. No change from the recent average except for normal variation.
I can’t see how the northern hemisphere can be warming without snow cover being affected. Snow cover is easy to measure by satellite. Temperature is harder and is prone to many technical issues.
It’s a load of rubbish. The pause in temperature is continuing unabated despite pCO2 rising more than 10% in the time period. You can’t fool snow with adjustments.
Also jetstream blocking events play a part, and may be more likely around the low point of the solar cycle, which is where we are this year.
https://physicsworld.com/a/split-or-strongly-tilted-jet-stream-brings-blocking-to-scandinavia/
“El Ninos leave a lot of heat behind in the atmosphere, which can take a long time to dissipate.”
That is not exactly right. Simple physics shows that any actual excess heat energy will be completely radiated away into outer space within weeks. What may be correct is:
“El Ninos change several physical conditions and their associated heat energy flows, and the dynamic balance-point of these can be perturbed for a long time.”
It is like getting a bruise. The actual energy in the blow is fleeting, but it takes time for the body to develop the mark and more time to get rid of it.
Adding to the confusion is that there are processes operating on quite different scales of both time and space. And, as Whitehead said, “If you try to talk about everything at once, you won’t say anything at all.”
Bit isn’t that the problem with climate? Unless you are talking about everything at once, you are saying nothing about climate.
Take you comment about El Ninos – aren’t they caused by changes in several physical conditions and their energy flows as well as causing them?
“…caused…as well as causing…”
Yes, lots of cases of “the chicken and the egg.”
And this is where many “scientists” go wrong when pontificating in generalities. You need formal cybernetic theory to guide you.
For instance, you have to have the following knowledge in your bones:
“The fact is that the concept of ‘feedback,’ so simple and natural in certain elementary cases, becomes artificial and of little use when the inter-connexions between the parts becomes more complex.”
W Ross Ashby , Introduction to Cybernetics, 1957.
The point is the ENSO is a known weather phenomenon – although prediction of it is poor as with many other modeled things – and to make claims of global warming when ENSO has occurred is either ignorant or lying. Take your pick over which it is.
El Ninos leave a lot of heat behind in the atmosphere, which can take a long time to dissipate.
I would have thought that the heat left behind was in the ocean as opposed to the atmosphere, where it would quickly dissipate, It is the water that retains its heat much longer than gases.
Reblogged this on Climate Collections.
“…the heat left behind was in the ocean…”
The El Nino / La Nina cycle does not involve a change in the rate of input of heat energy to the ocean; only a change in the rate of LOSS of heat from the ocean, through the surface, consequent on a change in the mixing pattern (the upwelling of cold water slows.)
When the satellite looks down during an El Nino, it sees a slighter warmer surface in a part of the Pacific than it does during a La Nina. And this is reported as an anomaly in the sequence of “brightness temperatures.”
The ocean is burping out a little more heat, but not because it is warmer, viewed as a whole. (When you open an oven door you will feel more heat on your face but it would be a mistake to interpret the sensation as the oven actually having a higher temperature while the door is open.)
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I agree that the the thermal capacity of the ocean is so large that the variations in heat loss are insufficient to cause any significant change to the overall heat content of it. But the extra heat is noticeable for a while in the atmosphere until it escapes to space. ONCE it has escaped to space it is ancient history.
Really, the cycle should be regarded as a correction to the “brightness temperature” figure rather than as a part of the temperature record. In other words knock off about 0.3 C during the peak of a strong El Nino and add 0.2 C during a strong La Nina.
We are entering a weak El Nino, and so this means that perhaps the satellite numbers should mentally be reduced by 0.1 C for a few months.