El Nino 2015 versus Global Warming 2015. Which caused the bigger temperature increase?
Guest essay by Sheldon Walker
The aim of this article is to split the temperature increase that occurred between the end of 2014, and the end of 2015, into 2 components. An El Nino component, and a Global Warming component. This will allow the size of the 2 components to be compared.
In order to do this we need to choose a temperature series. HADCRUT4 monthly temperature data will be used for the initial analysis, but the results for GISTEMP, NOAA, and Berkeley will be included for comparison with the HADCRUT4 results.
Graph 1 shows the HADCRUT4 monthly temperature anomaly plotted for the years 1880 to 2015. Also plotted is a LOESS curve for the HADCRUT4 data. The LOESS curve was generated using multiple local regressions, each regression using 20 years of data.
It can be seen from graph 1 that the most recent period of consistent warming started around 1975, and continued to the end of the data (December 2015). The LOESS curve shows that the warming trend is reasonably linear over the years 1975 to 2015. A linear regression will be done over this period.
Graph 2 shows the HADCRUT4 monthly temperature anomaly plotted for the years 1975 to 2015. Also plotted is a linear regression line for the same period. The slope of the regression line is 0.0175 °C per year. The total global warming over the years 1975 to 2015 is almost 0.72 °C.
The temperature change between the end of 2014, and the end of 2015, is 0.371 °C. (see calculation 1 – all calculations are documented at the end of this article)
We know from the linear regression that the temperature change due to Global Warming for 1 year is 0.0175 °C.
Therefore we can calculate that the warming due to El Nino is 0.3535 °C. (see calculation 2)
This means that the temperature change due to El Nino was over 20 times bigger than the temperature change due to Global Warming. (see calculation 3)
In other words, El Nino was responsible for over 95% of the temperature change between the end of 2014, and the end of 2015.
Global Warming was responsible for less than 5% of the temperature change between the end of 2014, and the end of 2015.
The results for the different temperature series are shown in the following table.
The percentage change due to El Nino varied from 94.3% to 95.3% for the 4 temperature series. The percentage change due to Global Warming varied from 4.7% to 5.7% for the 4 temperature series. A very consistent set of results.
These calculations are uncomplicated, and easy to do. The results are unambiguous. The results of these calculations should not be a surprise to anybody who is familiar with the climate. Think about what happened with the 1998 El Nino. The temperature zoomed up, and later zoomed down again. That temperature increase wasn’t due to Global Warming, it was due to El Nino. Do the climate scientists expect this El Nino to be different?
So it is surprising to see that a number of climate scientists have made statements about 2015 which minimise the effect of El Nino, and exaggerate the effect of Global Warming.
As you read the following quotes, remember that this analysis showed that El Nino was responsible for around 95% of the temperature change between the end of 2014, and the end of 2015. El Nino caused an increase in temperature of about 0.32 °C, but the climate scientists claim that it was only a few hundredths of a degree.
1) Quotes from an article called “Analysis: How 2015 became the hottest year on record” from CarbonBrief.org
http://www.carbonbrief.org/analysis-how-2015-became-the-hottest-year-on-record
Rising greenhouse gases and a “small contribution” from the El Niño in the Pacific combined to cause the record temperatures in 2015, the Met Office’s Prof Adam Scaife tells Carbon Brief.
…
How much of the record temperature in 2015 was down to El Niño?
—————————————————————
El Niño was growing in 2015 and only reached its peak this winter. So, we think El Niño made only a small contribution (a few hundredths of a degree) to the record global temperatures in 2015. – (Prof Adam Scaife)
…
Does that mean human activity was the biggest driver of 2015’s record temperature?
———————————————————————————-
Yes. The nominal record global average temperature of 2015 was well predicted in advance and well explained as being primarily due to global warming, itself mainly due to greenhouse gas emissions of human origin. El Niño made only a small contribution.” – (Prof Adam Scaife)
2) Quotes from an article called “Analysis: How much did El Niño boost global temperature in 2015?” from CarbonBrief.org
http://www.carbonbrief.org/analysis-how-much-did-el-nino-boost-global-temperature-in-2015
Carbon Brief has spoken to climate scientists working on this question, who all seem to agree El Niño was responsible for somewhere in the region of 10% of the record warmth in 2015.
…
Dr Gavin Schmidt, director of NASA’s Goddard Institute for Space Studies, described the ongoing rise in global temperatures as having had “an assist” from El Niño.
…
As part of Carbon Brief’s coverage of last week’s hottest-year news, we spoke to Dr Adam Scaife, head of the Met Office’s long-range forecasting division. Scaife suggested only a cursory role for El Niño, telling Carbon Brief:
We think El Niño made only a small contribution (a few hundredths of a degree) to the record global temperatures in 2015.
…
Schmidt estimated El Niño was responsible for 0.07C of the above-average warming we saw in 2015.
…
A quick comparison of either Schmidt or Cropper’s numbers with NASA’s temperature anomaly for 2015 of 0.87C above the 1951-1980 average suggests El Niño contributed about 8-10%.
…
Stott tells Carbon Brief: An estimate of less than 0.1C due to El Niño on 2015 global mean annual mean temperatures is less than 10% of the approximately 1C warming of 2015 relative to pre-industrial levels.
In other words, El Niño contributed “a small amount on top” of the warming greenhouse gases are already causing, says Stott.
There’s no doubt the El Niño that developed in 2015, which is still underway, has been abnormally strong, exceptional even. But with a contribution somewhere around the 10% mark, it seems clear from scientists that El Niño can’t be blamed for 2015’s record warmth. In fact, its contribution was strikingly small.
All of those scientists certainly seem to be singing from the same songbook!
I would like to see these scientists justify their comments, using numerical calculations to show where they got their figures from. I have fully documented my method here. If anybody can point out an error in my results, then please let me know.
Calculations.
1) [December 2015 anomaly] minus [December 2014 anomaly] = 1.005 – 0.634 = 0.371 °C.
2) [Total warming 2014/2015] minus [warming due to Global Warming] = 0.371 – 0.0175 = 0.3535 °C.
3) [warming due to El Nino] divided by [warming due to Global Warming] = 0.3535 / 0.0175 = 20.2
4) [warming due to El Nino] times 100 divided by [Total warming 2014/2015] = 0.3535 * 100 / 0.371 = 95.28 %
5) [warming due to Global Warming] times 100 divided by [Total warming 2014/2015] = 0.0175 * 100 / 0.371 = 4.72 %
It is wrong for the alarmists to pick one year or even two year temperature anomalies due to El Ninos and ocean data manipulations as proof of significant influence on global warming by man This is simple exaggeration of the threat . There is however a background century long term temperature trend of about 0.8 C/ century rise since 1900 and man may have played some role in this rise . In the short term, ENSO cycle and the 60 year climate cycle may raise and lower this trend in 30 year sub cycles . During the next 30-40 years the signs are pointing to a temperature trough or pause and not unprecedented warming . However , the temperatures are bound to rise again after the cooler period has done its cycle .. In my opinion a continued long term temperature rise is real, man does influence it, but the danger has been exaggerated both in severity and timing . We do need to do it right and we have the time , not in a panic mode as suggested by the alarmists. Shutting down coal plants before their useful life has expired is wasteful of the public purse and does not help the climate in any meaningful way .The current renewables are not the answer , We need to come up with new clean energy solutions and this is where our funds should be focused , not on wind turbines
herkimer:
You assert
Really!? The ‘Pause’ will last “the next 30-40 years” and then “temperatures are bound to rise again”!?
You know how long the ‘Pause’ will last and that it will certainly end with warming not cooling! That shows you possess astonishing prescience.
Please be so kind as to use your powers to tell me the winner of next year’s Derby.
Richard
Richard
Historical models show a cyclic trend . You may not use them but I do to look ahead .
http://www.woodfortrees.org/plot/hadcrut4gl/from:1880/to:2016
If you know better why don’t you present your idea instead of just making sarcastic comments about other peoples work .
herkimer:
The future is yet to be. It is not known.
I made no “sarcastic comments”: I ridiculed your claims of deific omniscience.
You now claim to have a model based on a “cyclic trend” but you did not say anything about your model, its indications, or the degree of certainty that can be attributed to its indications. Instead, you asserted what is “bound” to happen. That ‘crystal ball gazing’ deserves at least the amount of ridicule which I applied to it.
As for my “idea”, I have several. One of them is that unjustifiable assertions should be exposed and ridiculed for what they are. Indeed, that is why I have been an AGW-skeptic for 35 years.
Richard
Manipulation of the data and propaganda sciency sounding media reports does not change the fact that the majority of the warming (0.85C of 0.9C) in the last 150 years was due to solar cycle changes rather than the increase in atmospheric CO2. If that assertion is correct the planet can and will cool roughly 0.85C due to the interruption to the solar cycle.
The cult of CAGW have been able to keep the charade going, spinning away observational facts which disprove AGW such as the observational fact that there has been no warming for 18 years and the observational fact that there is almost no tropical tropospheric warming at 8km.
As Svensmark explains in his book ‘Chilling Stars: A Cosmic view of Climate Change’ due to the blocking of affects of the geomagnetic field the cloud mediated cooling is greatest between latitudes 40 to 60. A second very important cause of cooling in the same latitudes is an increase in wind speed over the ocean this mechanism is particularly strong in the Atlantic which explains why regions of the Atlantic ocean where 10C colder 150 years ago. A third cause of cooling is a reduction in cirrus clouds in the same latitudes (the increased ions cause the cirrus cloud crystals to get larger which causes them to fall.
A twist to the GCR mechanism is the fact that solar wind bursts remove ions at those latitudes (create space charge differential in the ionosphere which creates a potential difference between the poles and the equator) and in addition cause warming in the tropics due the electro potential that is created in the ionosphere between poles and equator.
There has been a one solar cycle delay in cooling due to the onset of solar wind bursts from coronal holes and mechanism that caused the blocking highs.
When it is obvious to everyone that the planet is cooling, climate change is going to move up to the top of the media discussion items.
http://www.amazon.com/The-Chilling-Stars-Cosmic-Climate/dp/1840468661
The cooling was started.
http://www.ospo.noaa.gov/data/sst/anomaly/2016/anomnight.2.4.2016.gif
If you watch the Royal Astronomical Society meeting – the Sun goes to sleep the are predicting much more drastic drops in temperature ~ -2C. The talk was given in July 2015 and they already predicted the high snowfall on the east coast.
Absolutely, the oceans milling around Antarctica are amazingly cold this winter which is a harbinger of the la Nina that is lurking in the near future. It will be a doozy. That is, cold as h*ll.
Do we know what causes El Nino / La Nina?
What they’re saying by implication is that the equatorial water is naturally warm and will cool because of upwelling cold water. Hmmm. The thing that gets me is the depth of the warm water. I really don’t find the usual explanations very satisfying.
Do the prevailing winds cause El Nino or does El Nino affect the prevailing winds?
That’s like asking ” Do the winds cause a hurricane or do hurricanes cause the wind ” !!
El Nino IS the prevailing winds and the changes in sea surface temperatures. There is something cyclic going on with cloud cover in the Western Pacific that ‘starts’ it off (if you can actually point to a ‘starting’ point, probably not). Bob Tisdale is good on this stuff; he put out a free e-book about it, linked somewhere on this side.
The sun’s cumulative effect is nonlinear and unpredictable outside of a limited frame of reference (i.e. scientific).
Sheldon Walker,
You’ve made one very basic error in comparing your El Nino contributions to the 2015 ‘heat’ and that of climate scientists. You’ve defined the 2015 heat as the change from 2014 to 2015. Climate scientists define it as the total change from a past baseline period, often (1950-1980 mean). Your calculations are crude estimates of the contribution of El Nino to the single year change form 2014 to 2015. They are not estimates of the contribution of El Nino to the total change in temp from the 1950-1980 baseline period (i.e. the anomaly).
Your own statistical model shows 40 years X 0.0175 C/year = 0.7 C of global warming since 1975. So there is 70% of the 2015 anomaly. So, if you want to use the residuals from a simple linear trend to attribute El Nino contributions to the anomaly, you could perhaps claim that El Nino contributed up to 30%: or less than a third (a fair way from your more than 20 times as much claim!!). You’d be wrong (see below), but at least you’d be comparing apples with apples.
Of course factoring out contributions from non-linear & interacting factors is very difficult, and can’t seriously be done with a simple linear regression between temperature and time. Here is one of the (many) better approaches (since you asked):
https://tamino.wordpress.com/2016/01/27/el-nino-and-the-2015-record-breaking-heat/
tamino, really?
Excellent rebuttal. I now see the fundamental flaw in tamino’s analysis: someone on the internet doesn’t like the results.
Who said skeohane’s reply was a rebuttal? Its more like throwing up a little in your mouth. More of a reflex really. Nothing at all to do with his analysis. 🙂
Exactly my point.
Jim:
Please clarify.
Are you claiming that tamino has at last got something right and – if so – why do you think he is not willing to put his real name to it?
Richard
Ahh, now I see the flaw in tamino’s analysis: someone on the internet doesn’t like his results, AND tamino is a pseudonym! Not sure how I missed that.
Jim from your link 2nd sentence
“Their favorite candidate is something that does in fact make Earth’s surface get hotter, something that really did contribute to 2015’s record heat: el Niño.”
I’m sorry, but El Nino is in fact a cooling event, the oceans cool during El Niño events, (it’s where the heat was hiding !!!)
Why is the 1950-1980 “baseline” more appropriate than the 1910-1945 “baseline”?
According to AGW theory, the 1950-1980 period is polluted by human activity with a global warming signature, so it would be an inappropriate baseline. If you use the 1910-1945 trend previous to the “CO2 Era”, how does that same analysis turn out? Nearly identical to Sheldon’s analysis.
It isn’t – but it wouldn’t make any difference to the calculated trend. The monthly temperatures are represented as anomalies with respect to a baseline period. If the mean temperature for 1910-45 was 0.1 degree warmer than for 1951-80 (it’s not) then the anomaly for 1975 would be 0.1 degree lower – but so would the anomaly for every other year. The trend would be completely unaffected.
KTM:
You say
There is no evidence for AGW; none, zilch, nada. Three decades of research conducted world-wide at a cost of more than$5 billion per year has failed to find any. In the 1990s Ben Santer pretended to have found some such evidence but that was soon found to be an artifact of his selecting data from a part near the middle of a time series.
AGW is at best an hypothesis and more properly a conjecture. It most certainly is NOT a theory because it has no supporting evidence; none, not any.
Richard
I must admit that I suspect, in this case, Tamino’s analysis might not be too wide of the mark. The extent of the “cooldown” after the El Nino should provide a good test.
All el Ninos are ‘yin/yang’ events because they are all followed by la Ninas and the stronger the el Nino the more powerful the la Nina. Naturally, not one global warmist dares mention this fact or explain why this happens.
Hi Jim,
I subtracted the December 2014 anomaly from the December 2015 anomaly. Both of these values are relative to the December baseline. By subtracting I remove the baseline, and get the absolute temperate change, which is exactly what I wanted.
Aren’t all climate temperature calculations crude estimates? They are all we have. Hopefully better than nothing.
I was interested in looking at what made 2015 a record year. i.e. bigger than the previous record year. Any baseline (like 1951 to 1980) is an arbitrary choice. Different temperature series use a different baseline. Which one should I choose, and why?
Speaking of baselines, what do you think about setting a temperature limit based on pre-industrial temperatures. As far as I can see, pre-industrial times is the same as the little ice age. The 1.5 or 2 C limit is arbitrary. So we are setting an arbitrary limit from a time when the earth was abnormally cold. I am sure that somebody put a lot of thought into that.
The point is that what made 2015 a record hot year is the gradual accumulation of heat over decades (the AGW component) plus the short term El Niño spike. By calculating only the annual change, you remove almost all of the AGW component: all you’re left with is the short term variation. The AGW contribution to 2014 temps took decades to accumulate, it didn’t magically disappear on Dec 31 2014. But that is what you are effectively claiming by basing your calcs on the difference between 2015 and 2014.
There are all sorts of difficulties in teasing out contributions from El Niño and other factors to particular months or years weather. It’s probably not even possible with a purely statistical approach, but if it is, you need a more complex multivariate analysis that tries to account for interactions and time lags. Taminos post is an example of that. Try reading it.
So you smoothed the chart and declared that global warming was responsible for only the trend portion, and El Nino is responsible for the rest?
Not buying it.
I thought it took 30 years to see a climate trend??
Now the 30-year trend is the noise and the 1 year trend is the global warming signature…
KTM:
Upthread you made the same untrue assertion about “30 years to see a climate trend” and I replied by explaining it is a falsehood here.
Contrary to warmunist doctrine, repetition does NOT convert a falsehood into truth.
Richard
The Art Of Misdirection
“The unprecedented record temperatures of last year can be explained by migrating Zorkons”
“I’m sorry there is no evidence for Zorkons, in fact Albudalins are the real problem as my latest peer reviewed study shows”……
and so on until a still small voice asks querulously
“What unprecedented record temperatures would those be then? I see no broken records…. “
1. The global average temperature anomaly – built based on poor data distribution in space and time on land & ocean — consists of trend superposed on it the systematic variations consisting of intra-seasonal and intra-annual and 60-year cyclic variation;
2. The global average temperature anomaly trend was adjusted every now and then to meet the global warming prophecies – past data was lowered by 0.25 to 0.3 oC and current data taken upward. Lately this was further corrected upward to remove hiatus-pause [which is clearly seen in satellites data series] and thus this rise is 0.25 oC during the hiatus period alone;
3. While meeting the global warming prophecy, they forget the fact that the global average temperature anomaly consists of several local-region specific changes in temperature that goes into global averaging – heat-island effect is over emphasized and cold-island effect is under emphasized and thereby added positive increase to average;
4. Thus, the trend consists of global warming component, non-greenhouse effect component [land-use & cover and water-use & cover changes] component, filth covering land & ocean component, natural & man induced aerosols component, etc;
5. Also, El Nino is accompanied on either side of the peak, depressions;
6. The author of the present article simplified the issue by assuming that the global average temperature anomaly consists of El Nino component and global warming component. It is flawed assumption in light of the above;
7. Since 1979 [satellites data] to date, the data could be divided in to two parts, namely: prior to 1997/98 [El Nino] and after 1987/98. Both the series present zero trend. By fitting the 37 years data to sine curve you get the trend – zero only as the former part goes to below average part of the sine curve associated with volcanic cooling and the later part goes above the average of the sine curve associated with El Nino warming. The zero trend is the hiatus-pause of around 19 years;
8. Also, all the light emitted by the surface in the strongest CO2 bands was completely absorbed at pre-industrial levels [280 ppm];
9. In light of these, the author of the article needs to re-work the calculations, keeping in mind that global warming is not a global in nature.
Dr. S. Jeevananda Reddy
Further to the above, it may be appropriate to look at data series of the core El Nino zone and try to show the same.
Dr. S. Jeevananda Reddy
The underlying assumption seems to be that the process is linear. If I were mixing beakers of water in the lab, that might be appropriate. For the climate, where phase change is important, it probably isn’t. For instance, thunder storms in the tropics are a highly non-linear response to surface temperature.
CommieBob — You mentioned that thunderstorms in the tropics are highly non-linear response to surface temperature. It is not correct. It relates the difference of dew point temperature between 850 and 700 mb, as above 700 mb it is nearly dry. Here moisture of importance —my paper — Indian J. Met. Hydrol. Geophys., 29:255-257.
Dr. S. Jeevananda Reddy
Neither HadCRUFT4 nor any of the other “land+sea” indices are measuring anything physically meaningful. You cannot “average” the temperature of a block of steel and box of feathers. It’s meaningless BS.
It only makes sense to average the temperature of different volumes of the same media. Land+sea is as meaningless as averaging deg F and deg C.
After thinking about it, I am having a problem accepting this analysis because it is based on the difference between 2 Decembers a year apart. For a single month, anything can happen for reasons we cannot explain and I do not think it wise to read too much into things when comparing just two months. For example, here is a comparison of anomalies for April and May of 1997 and 1998 for RSS:
(I hope the formatting works!)
My question is this: Which anomaly difference best represents the affect of the 1998 El Nino?
Hi Werner,
I think you need to be clear about what you want to measure.
I was interested in the temperature change from El Nino over the year 2015. So subtracting the December 2014 anomaly from the December 2015 anomaly gave me a reasonable result.
If you are interested in a complete El Nino then it probably won’t fit neatly into some number of years. I think that you would need to look at all of the months that the El Nino covers. Depending on what you want, smoothing may help. Be careful if comparing 2 different months, because the 2 anomalies may have a different baseline. For this reason, I wish that they would tell us the baseline values, but they seem to want to make things difficult for us.
Thank you for your reply. Let me illustrate my point by comparing October with December on Hadcrut4.
By comparing two Decembers, you get 5%, but had you compared two Octobers the same way, you would have gotten 10%.
I agree with that. However doing an average of at least three months would have given a more realistic value in my opinion.
Sheldon, don’t use HadCRUT4 or any other ground-based “official” temperature curve. They have all been tampered with to show non-existent warming. The only temperature curves that are still honest are satellite temperatures. To show you how HadCRUT4 (and NOAA also) lie about temperature look for comparison at Figure 15 in my book “What Warming?” First, your graph 1 shows a non-existent warming from 1980 to the start of 1997. There is no warming there and a hiatus exists but they show it as a temperature rise of 0.35 degrees Celsius. It is not a statistical error but a deliberate falsification that has been on the record since 1997. I discovered in 2008 that a hiatus visible in the eighties and nineties in satellite records had mysteriously morphed itself into a “late twentieth century warming” in official temperature graphs. I mentioned it in comments and put a warning about it into the preface of my book in 2010. Nothing happened, I was completely ignored, and they still are purveying that criminal data set for its nineteenth year. This actually is not the only falsification in this graph. They also show warming in the twenty-first century where another hiatus exists. This is the one that NOAA tried to get rid of when they invented the water temperature data set ERRSTv.4. They christened it as “pause-buster.” Whether or not warming exists there depends upon the starting point of that hiatus. When it begins with the super El Nino of 1998 it does look like warming. But the 21st century hiatus does not begin with the super El Nino but with the year 2002. That is the year when the step warming of 1999 which raised the twenty-first century above the twentieth ended and the actual hiatus began. And if you make 2002 the starting point of the hiatus the next ten years are not warming but cooling. That step warming of 1999, by the way, is the only actual warming that took place during the entire satellite era that began with1979. Both your graph 1 and graph 2 are totally out of touch with reality. In view of what I said about temperature you ought to be able to see that graph 2 is totally wrong because it attempts to show a straight line relationship that does not exist. And to cover up their falsification they use such poor resolution that you have no idea that ENSO phases even exist in their data. There are actually five El Nino peaks in the eighties and nineties before the super El Nino shows up as you will note in my Figure 15. They are impossible to recognize in either of your graphs. And why go to the bother of getting rid of hiatuses? Very simple. During a hiatus carbon dioxide keeps increasing but temperature does not. This is a violation of the greenhouse theory of Arrhenius, still used by IPCC, according to which increase of carbon dioxide in the atmosphere should warm the air by the greenhouse effect. Since it does not do so during a hiatus, it follows that there is no greenhouse effect and the Arrhenius theory is invalid and belongs in the waste basket of history. And with it dies the theory of global warming.
Arno Arrak (@ArnoArrak):
You say
I share your concern about “HadCRUT4 or any other ground-based “official” temperature curve”, but I dispute your assertion that Sheldon should have used the “still honest are satellite temperatures” for his analysis.
Sheldon’s analysis assesses claims of warmunists who base their claims on the “ground based” data and, therefore, his assessment needs to be of the “ground based” data.
Richard
Arno, a suggestion: Please break up postings with paragraphs so they are readable. Reading from a computer screen is easier if you have more paragraphs. Even on paper, this is a way too big paragraph.
I’ve tried to tell Arno this more than once, but he doesn’t seem cognizant of how his writing appears.
Arno;
I’m sure your post is enlightening & full of good information, sadly I & most others without 20-20 vision will never know, as without paragraphs the lines all merge to form an incomprehensible mass of gobbledygook, so we don’t bother reading it.
If few/no people are going to read it….why bother writing it ??
Seeing you wrote your book in the same style I doubt many will buy it, the graphs look OK but are meaningless without readable text.
As you obviously enjoy stringing things together, why not take up embroidery or necklace making.
HadCRUT4 is not data but altered data. You cannot make assumptions based on nondata. Satellite data should be used because this data covers more of the planet, ie. it covers the oceans with no guesses. Even with all this it is impossible to calculate human input because this is so small in comparison to natural inputs like the sun/El Nino etc. We still fail to understand El Nino completely and how it affects the planet’s weather to make the bold claims posted above.
I checked the 25 year trend in Waterloo and it is down. The minima are trending up but the mean and max trend is down. So is the 15 year trend. The record low around this time last year was -34.5 C. This year it is very warm for January-Feb. Long may it continue. The population is saving a fortune. Cities are saving a fortune.
The current El Niño, active since summer 2015, is one of the three strongest ever recorded, as long as one reduces the observation period to the last couple of decades. However we know that there was a El Niño during the first winter in World War II (WWII). In Europe the winter was the coldest for more than 100 years. (HERE) In the U.S. a number of States experienced an extraordinary dry and warm autumn 1939, and record cold in January 1940 as well: http://1ocean-1climate.com/in-el-nino-matters-ask-the-experts-but-expect-nothing/. On the other hand, if you want to take a look to a tiny cold hole in hottest year, here it is: http://oceansgovernclimate.com/a-tiny-cold-hole-in-hottest-year-fine-art-not-more/ 🙂
“Yhe aim of this article is to split the temperature increase that occurred between the end of 2014, and the end of 2015, into 2 components. An El Nino component, and a Global Warming component. This will allow the size of the 2 components to be compared.”
You can’t be serious? You can’t do that.
So what was the global temp in 1998 under this mathematical model? Would the result suggest that beginning a trend analysis on or near 1997/1998 would give undue weight to a massive anomaly in the record, particularly considering the (climatically) short time-scale?
Hopefully analyses in the future will run peak to peak or trough to trough for comparably large ENSO events. Peak to trough or the reverse would be a certain skew of the record, just as running a trend for sea ice from winter year X to summer year Y would be a big skew; just as running a trend for solar cycles from a peak to a trough would be misleading.