Hottest year ever update: El Niño effect in 2015 was 20 times larger than the global warming signal

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.

El Nino graph 1 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.

El Nino graph 2

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.

El Nino 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 %

 

122 thoughts on “Hottest year ever update: El Niño effect in 2015 was 20 times larger than the global warming signal

  1. Personally I find nothing at all surprising in climate scientists talking up the global warming aspect and underplaying the El Niño contribution.
    It’s what they do, but it will catch up with them one day.

  2. It was hysterical watching the warmists cheer on the El Niño like it was some kind of a football game. They were too ignorant to realize that the huge temperature forcing impact of El Niño and oceanic circulation in general implicitly revealed the minimal forcing effect of additional carbon dioxide upon atmospheric temperature. The oceans are the big dog in the temperature story. Carbon dioxide is just a bunch of fleas on the dog.

      • The climate alarmists were waiting for a break in that inconvenient 19-year global warming pause. So El Nino helped them out tremendously. Mother nature can be kind, even to climate alarmists. But she does have La Nina waiting in the wings, so mother nature is a lady with many different facets; a truly playful bitch.

    • Funny indeed, like it actually proved their AGW crap when in fact it proved the opposite: showing the importance of natural variation.

      The LOESS curve was generated using multiple local regressions, each regression using 20 years of data.

      Sheldon , what is this ” a LOESS curve” ?! There is a LOESS filter
      but I’ve never heard of your LOESS curve.

      How did you cherry-pick your 20y period? If you are doing some home-spun linear trend fitting , do not call it “LOESS” which suggests it is applying an established filter technique of that name.

      • 20 years is two decades so not exactly cherry picked when discussing decadal trends.

        Mike, from this and other comments, you seem to have a better way to characterize the long-term trends in the data. Could you write it up remembering the large uncertainty in monthly anomalies and that to an expert in using a hammer, everything is a nail.

      • Robert, just because it’s a round number does not make it an objective choice. IPCC prefer “the latter half of the 20th c. ” , sounds like an innocent round number but cherry-picks the warming period.

        I don’t know why Sheldon “likes” the results using 20y, he does not say. But my main objection is is calling this ad hoc processing “LOESS “, which is an accepted filter and is NOT what he is doing.

        If he wants to call it the Sheldon curve , fine. We can discuss the merits ( or not ) of his “innovative” method.

      • Mike,

        according to wikipedia:
        https://en.wikipedia.org/wiki/Local_regression

        A smooth curve through a set of data points obtained with this statistical technique is called a Loess Curve, particularly when each smoothed value is given by a weighted quadratic least squares regression over the span of values of the y-axis scattergram criterion variable.

  3. Well done Sheldon Walker. You have made the case as plain as day. And of that 5% which is not of the El Nino impact, it is still an unknown as to how much of man-made atmospheric CO2 is even responsible for that 5%. I suppose that when global temperatures do take a large nose dive in the next few years, climate alarmists will start to blame La Nina for all of the drop.

  4. Well, the fact is that 2015 was record from January thru April, when there was no El Niño, and I think the spring/summer values (when the ElNiño was getting going) were some of the lowest of the year.

    And a question, I must of missed it in your write up, are you using only the first year in your analysis of El Niño warming. Like 97 not 98 and 2009 not 2010, etc?

  5. “We know from the linear regression that the temperature change due to Global Warming for 1 year is 0.0175 °C.”

    Ah no you don’t know that.

    here is what you can speculate.

    1. Assume the contribution of natural forcing (internal variability) is ZERO over the time period.
    2. Assume there is no interaction effect between natural and forced warming.
    3. Assume that the data generating model ( the physical process) is best represented by a memoryless
    linear process ( you apply a linear model using only current time)
    4. You can fit a linear model with some error ( which you dont report) to estimate.
    5. A linear fit assumes the underlying data generating model is linear with time.. we know
    this to be physically impossible over long periods of time. We dont know it’s validity over
    shorter periods of time. sidebar: linear fits are useful for comparing two or more
    data series of the same thing over time — like comparing hadcrut to BE. They are
    less useful for untangling natural from forced variation in a single data series.

    Assuming all that you can show a Fit for that model over the time period.
    the fit has a slope which you report
    the fit has residuals which you dont report
    the ESTIMATE of the slope has a confidence interval which you dont report.
    the fit has residuals which you dont report.

    So assuming all that you assume, the MODEL has a change per year.
    The data is not the model.
    the model is not the data.
    the model is used to explain the data.. It explains a portion and doesnt explain a portion ( the residuals)
    it doesnt give you knowledge, it gives you belief subject to the truth of your assumptions, many of which cannot be tested independently.

    Your’s is but one way to attribute a temperature rise. There are multiple ways. each fraught with assumptions. Since there are multiple ways, you have to establish that your way is superior. you havent.
    When and if you have established the superiority of your method ( by looking at multiple ways and being skeptical of your own analysis) Then you can make a claim about explaining the data better than other methods. Explaining data better gives you provisional and contingent belief– not knowledge. It can be well founded belief, it can be our best belief, but like all science it is contingent and provisional.

    Untangling the natural portion of the warming from the forced portion of the warming is easy to do with many simplifying assumptions. Sadly, reality isnt so simple.

    And yes, those who claim a lower contribution from el-Nino are likewise limited in what they can say with certitude.

    For grins.. take your time series and make a time series going back to 1880 using only el nino years
    Do the same for La Nina

    • Steven Mosher

      For grins.. take your time series and make a time series going back to 1880 using only el nino years
      Do the same for La Nina

      An interesting, perhaps important challenge.

      If I were to do that – or wanted to do that – what then do you consider “El Nino” years, and which are “La Nina” years?

    • IT looks to me like everything you are suggesting are assumptions, yet somehow there is something other than assumptions when we talk about AGW? Science is assumptions and never truly “proofs” anyway, which is why we really know we are talking about theories and not “laws,” even when the word is used. There is always the chance that they can be disproved by some quirk or another.

      And in reference to climate models – the model explains nothing beyond what the programmer assumed, and has no more value than anything else written on a cocktail napkin. I’ll take that back, there are signatures on cocktail napkins that due have value, but climate models are signatures in the same sense.

    • 1. Assume the contribution of natural forcing (internal variability) is ZERO over the time period.

      Did he forget the deep oceans eating up heat and now regurgitating it during the current El Nino? I guess he did assume that it wasn’t happening but I could come up with another dozen possibilities (some more outlandish than others) that he ignored before I finish my coffee. Meanwhile, you’re quite happy with the assertion that the high anomaly for 2015 is nearly all due to anthropological global warming based on what? That the deep oceans ate up the extra heat and now is regurgitating it during the current El Nino?

    • Mosher says: “For grins.. take your time series and make a time series going back to 1880 using only el nino years Do the same for La Nina”.

      Well, a person can go back to 1856 if your want and use the monthly data (not the crappy annual data that you were thinking of) …

      … and not only adjust for the El Ninos and La Ninas, but also for the AMO (the 60 year cycle in temperatures which is a real thing) and the volcanoes and the solar cycle …

      … and one gets a very good monthly model of Hadcrut4 all the way back to 1856 – over 1900 monthly datapoints.

      Then we pull out the natural variables and leave just the ln CO2 warming trend. Just a very consistent white noise series that approximates the actual CO2 warming over time (just back to 1979 so it more clear).

      Sorry, it is only about half of that predicted in the global warming theory and your cherished Climate Models.

      And let’s remember this is the “adjusted up” Hadcrut4 temperature series. The “unadjusted” lower troposphere temps are only warming at 0.042C per decade using this same methodology and do not even come close to the global warming theory and your cherished Climate Model results

      • How reliable is Hadcrut 4 for 1856,1880, 1900 ?
        There must be be a huge amount of interpolation across the planet up until the 1950s.
        Who was taking measurements in place such as the Amazon, central Kazakhstan, northern Western Australia and Heard Island in 1856?
        I suspect the error bars are rather large

      • Don’t forget no data from the north or south poles and 90% of Africa and so forth. Heck, zero data from Arizona, New Mexico, Nevada, too, back in the 19th century.

  6. The average Nino 3.4 value between Oct 2014 and September 2015 was only +1.07C (Oct to September to account for the 3 month lag.)

    http://www.cpc.ncep.noaa.gov/data/indices/sstoi.indices

    Regressions indicate that the Nino 3.4 impacted 2015 temperatures by between:

    –> 0.08 * Nino 3.4(1.07C) = 0.086C (surface temps regression)

    to

    –> 0.13 * Nino 3.4(1.07C) = 0.139C (lower troposphere temps regression)

    • You do realize that it’s the ENSO process that’s affecting global temperatures, not the specific contribution from that particular piece of geography? Right??

    • Here is the lower troposphere temperature record – the satellites and the weather balloon data-radiosondes going back to 1958 – versus the ENSO.

      Points to make:

      – yeah, the ENSO is a huge controller of the lower troposphere temps;

      – sorry, there is very little global warming in this scenario of 57 years (when it is supposed to be increasing at 1.3 times faster that the surface at this level of the atmosphere – the surface records only show you an unreliable record if you want an unreliable record);

      – there is a lag of 3 months from the Nino 3.4 to when the lower troposphere is impacted and this operates on a continuous on-going basis every month;

      – one can see the volcanoes certainly do get it the way and the straight one-to-one relationship but if you made adjustments for the volcanoes (which is not hard to do, I have done it), the relationship would be very clear; and,

      – the temp anomalies are not going to peak until next month – February, 2016 – global lower troposphere temps will approach 0.7C and the tropics may exceed 1.0C. Then it will drop slowly as the ENSO has dropped slowly since November, 2015.

      • Nino 3.4 is by far the best measure of the ENSO’s impact on the climate. It always has the best correlations to temperatures, water vapour, the trade winds and cloud formation of the various ENSO measures. Just use it alone.

      • Bill Illis, you say:
        “Nino 3.4 is by far the best measure of the ENSO’s impact on the climate. It always has the best correlations to temperatures, water vapour, the trade winds and cloud formation of the various ENSO measures.”

        Yes. Only NOT during the actual lifts in the mean level of global temperature. Which is what “global warming” is all about. So if you use NINO3.4 to represent the entire ENSO process, you get the distinct impression that something else causes the “global warming”. When it isn’t. It is STILL the ENSO process causing it, only not the NINO3.4 part of it:

  7. I’m not sure what the point of this post is. Of course, the El Nino was responsible for most of the spike in temperature but this spike came on top of already elevated temperatures. We’ve had El Ninos before but not had the same level of warming (UAH and RSS are both reporting record January temps). The 1982-83 El Nino was almost as strong as this recent one but UAH anomalies throughout 1982/83 barely climbed above the mean 1981-2010 threshold.

    If a La Nina follows the current El Nino then temperatures will inevitably fall but it’s doubtful if they will drop as far as temperatures during the 1982/83. El NIno period.. In other words, temperatures during La Nina nowadays will be higher than during El Nino of 30-odd years ago.

    I don’t see global warming as a major problem but can we stop pretending it’s not happening. It is – slower, perhaps, than predicted by the climate models but it’s happening nonetheless. .

    • JF – seem to be somewhat hard of understanding.

      Nowhere does this posting claim, imply, or otherwise hint, that global warming is not happening. It simply demonstrates that the alarmists from the Met Office and elsewhere are simply wrong to claim the the El Nino added a minor amount to last years record warming.

      • “It simply demonstrates that the alarmists from the Met Office and elsewhere are simply wrong to claim the the El Nino added a minor amount to last years record warming.”
        ———-
        Yes, and that all comes back to the meme of “record warming”… record since the Little Ice Age, ala “Warmest year ever recorded”, or record in all of mankind’s recorded history? The slope of the rise in temperatures from the Little Ice Age to the 1950’s isn’t much different than the slope of the rise in temps since 1950 and most would agree that man’s addition of CO2 to the atmosphere mattered little, pre- 1950’s.

      • Arriving in London in 1959 from the South Pacific a steam engine was pulling the train, looking out the window I could hardly make out the terraced houses as we passed for the soot/smog, heating was with coal, trains were powered by coal, electricity was generated by coal, ships were powered by coal, gas was made from coal, and during the 2nd word war most transport was driven by a coal/gas converter., walking down Bond Street the second day in London I could not see the other side of the street, (looking fort a shop that i passed 3 times ) this was “normal” for the time. The world wants to take a history lesson, what happened yesterday is forgotten by tomorrow.

      • JF – seem to be somewhat hard of understanding.

        Not at all. For a start, it’s by no means certain just how much the El Nino contributed to the increase in global temperature. Just because the trend happens to be 0.0175 deg per year since 1975 it doesn’t mean that the temperature will increase by 0.0175 degrees every year. The AGW element may have been suppressed by natural factors in the previous few years and is now playing catch up. I don’t think we can say anything about the El Nino effect until a few more years pass and we can see at what level the temperature anomaly settles when ENSO is nearer neutral.

    • We can stop pretending that Global Warming (AGW) has a statistically scientific impact on global climate when there is no evidence for the claim (besides deception, conjecture, and hyperbole).

    • A least squares fit from 1976 to 1998.5 (cherry picked to get the largest trend) is 0.181K/year. Add that to the 1976 anomaly and it comes out to 0.94 so a little short of the Dec anomaly for 2015. I’m guessing that this is used to justify that its nearly all AGW. Where are those insisting that natural variability needs to be taken into account?

      • ie. how much of that 1976-1998 warming was heat stored in the deep oceans from the 50-70 pause that came back to bite us?

    • The exact quote is ”WE don’t BELIEVE in that HERE.” (properly processed thermodynamics that come up with correct answers that agree with experimental proofs)

      And ”We BELIEVE in the Green House Gas Effect here.”

      Not ”We discuss the atmosphere as a light robbing thermally conductive self refrigerating, turbulent fluid bath,
      reducing energy to the surface by a fifth,

      to then emit that reduced energy

      from an overall larger, colder mass, which is the definition of

      cooling.”

      No, ”We believe the sky is a giant heater and if you don’t then you have the wrong friends!”

      It doesn’t matter to a magic gasser that the atmosphere is indeed – a frigid, self refrigerating fluid bath robbing light from a sun warmed rock, to then emit that LESSER energy from an overall larger, COLDER mass.

      The sky is a heater because that’s where the money is right now, so we don’t need any talk about the actual measured activity of the atmosphere.

      Reducing energy to the surface,
      scrubbing the remainder off to emit it from an overall larger colder, mass- that’s irrelevant to the ”belief” of a magic gasser.

      That’s why insisting ”nobody discuss the atmosphere as anything but a giant, magical heater,”

      is the sole answer magic gas believers have

      to all the MANY facts slapping them directly in their faces about the crock of thermodynamic garbage they’ve preached to all the face of the planet.

      Magic gassers are what is equivalent to mobs: to them, right and wrong has zero to do with it.

      (1)Who are your friends?

      (2)How big an audience can you manipulate?

      (3)Scientifically valid, experimental proofs? We’re ABOVE that sh**.”

      That’s the magic gasser religion in three quick steps.

      kokoda
      February 4, 2016 at 8:49 am

      Numerical analysis is not important. “We think” is the science of the day.

  8. From one of your links:
    http://www.carbonbrief.org/analysis-how-much-did-el-nino-boost-global-temperature-in-2015

    Schmidt’s analysis suggests 2015 would have still been a record-breaking year even without El Niño. After removing the estimated contribution from El Niño of 0.07C, the average global temperature in 2015, according to NASA, would have been 0.8C above the 1951-1980 average.

    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%.

    You say:

    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.

    Schmidt says that 0.07 of the 0.13 increase for 2015 is due to the El Nino. If this increase is from El Nino, then 0.07/0.13 = 54% is due to El Nino when comparing 2014 with 2015. However Schmidt compares the 0.07 to the overall increase of 0.87 to come up with 0.07/0.87 = 8%.

    There were no mathematical errors in your work. However you just compared December 2014 with December 2015.
    I note that you disagree with Schmidt and believe that of the 0.13 increase in GISS from 2014 to 2015, 0.0174 should be due to natural variation. If so, that would mean the increase of 2015 over 2014 was 0.0174/0.13 = 13.38% natural and not 5.1% natural.

    • It all depends on what you use as the baseline/denominator.

      They use a horizontal period from 1951-1980 that itself appears to be an anomaly give the rest of the temperature record.

      I would argue that the best period to use as the baseline would be 1910-1945. This is a “warming period”, which they say we are in. Why compare a warming period to a horizontal anomaly period, that makes no sense. And from 1910-1945 they would not blame the warming on CO2, so it represents natural climate variability during a warming period.

      If you set that incline as the baseline, you would get something nearly identical to what the author calculated here.

  9. Thanks, Sheldon Walker, for a very clear exposition.
    Yes, 95% natural El Niño vs. 5% other causes, probably mostly natural too, makes a lot of sense.
    I guess the HADCRUT3 in the header for your table is a typo for HADCRUT4?

  10. El Niño is a cooling event. All the heat released from the ocean that doesn’t find its way back into the ocean is headed out of the earth system. It is an impulse. A very natural impulse, and it has done its job. It will happen again. This isn’t climate or even weather – it is Earth dynamics that is an inevitable consequence of the Earth’s oceans, atmosphere, and land masses with a little help from a friendly local star and a chance favorable orbit around that star.

    • “El Niño is a cooling event.” To upper OHC yes, but it’s also a negative feedback to a decline in forcing, such as stratospheric volcanic aerosols, or slow solar wind periods, e.g. 1997/98 and 2009/10:

  11. Unless the ENSO effect influences the overall energy balance through means not yet explained to me it CAN NOT influence mean global temperature, It can influence READINGS in the various zones (atmosphere, marine, land surface) but this should net be used as evidence in GW debate

    According to the current model on ENSO it simply redistributes heat in various concentrations in various locations and zones

    In the final analysis the use of the ENSO effect in the debate further substantiates just how flawed surface measurements are in establishing mean global temperature change over time

  12. “Therefore we can calculate that the warming due to El Nino is 0.3535 °C.”

    You have no basis for that. All your analysis says is that
    1. There was a steep rise in 2015. Well, we knew that.
    2. If you smooth sufficiently, with LOESS or regression, there is only a small rise. That is what smoothing does.
    3. So there is a difference. Well, yes.

    You offer no basis for saying that the difference is due to El Nino. The difference from the scientists that you quote is that they have actually tried to calculate what this El Nino would actually have done.

    • If it takes 30 years to see a climate trend, why should we look at annual wiggles in the data to determine the human contribution?

      But that raises a good point that since he is attempting a climate analysis it should have been a 30-year filter applied, at minimum. And then he should have compared the climactic trends observed before the “CO2 era” and since to determine the baseline of natural climactic variability during this interglacial (natural warming) period.

      • KTM:

        You ask

        If it takes 30 years to see a climate trend, why should we look at annual wiggles in the data to determine the human contribution?

        It does NOT take “30 years to see a climate trend” and, therefore, your question is a ‘Have you stopped beating your wife” question.

        The reason for considering annual changes to determine the human contribution to an ENSO spike is because the spike lasts only a few years at most.

        In its 1994 Report the UN Intergovernmental Panel on Climate Change (IPCC) used 4-year periods to assess climate variations in hurricane frequency, and the above analysis assesses differences between individual years to determine variations from a temperature trend. Both these assessments of climate trends are appropriate because The IPCC AR5 Glossary defines climate as being

        Climate
        Climate in a narrow sense is usually defined as the average weather, or more rigorously, as the statistical description in terms of the mean and variability of relevant quantities over a period of time ranging from months to thousands or millions of years. The classical period for averaging these variables is 30 years, as defined by the World Meteorological Organization. The relevant quantities are most often surface variables such as temperature, precipitation, and wind. Climate in a wider sense is the state, including a statistical description, of the climate system.

        So,
        climate is ‘average weather’ over any “period of time ranging from months to thousands or millions of years” but the period needs to be stated.

        This thread is about changes of individual years from a 20-year running mean and both are stated. The purpose is the stated attempt to separate the effect of ENSO on the annual change and, thus, to reveal the maximum possible contribution of AGW to that change.

        The 30 years refers to a standard period to which climate data is compared for generation of ‘anomalies’: it is NOT climate. And its length is arbitrary: it was adopted in 1958 as part of the International Geophysical Year (IGY) because it was thought that there was insufficient data for use prior to 30 years before 1958. It is an unfortunate choice because 30 years is not a multiple of the solar cycle length, ot the Hale cycle length, or any other climate cycle length.

        Richard

    • Hi Nick,

      1. Could AGW be responsible for the steep rise in 2015?
      2. Smoothing shows you the average, or what “normally” happens.
      3. Taking what “normally” happens, away from what did happen, leaves you with the “not-normal” part.

      In this case the El Nino is the “not-normal” part.

      If “the scientists” would like to prove me wrong, then good luck to them. I find it very difficult to believe that El Nino has only caused a few hundredths of a degree warming. What happened in 1998?

      • “What happened in 1998?”
        The relevant question is, what happened in 1997? In fact, the main El Nino rise in 2015 started in October. Now you can say that 2014 (record) and early 2015 were at least ENSO neutral. But then what does “due to El Nino” mean?

        The shallowness of your logic is seen if you look at the other residuals in graph 1 or 2. Almost always there is a change much larger than the change in the underlying smooth. Is that always El Nino? What is the rule?

  13. “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)

    So what explains the 1998 super El Niño’s record temperatures above the historical mean?

    I find it disingenuous of these “scientists” to imply that an El Niño effect is only evidential at its peak for explaining a year-long temperature record. I call BS.

  14. “We know from the linear regression that the temperature change due to Global Warming for 1 year is 0.0175 °C.”

    A large proportion of what you are measuring there is the natural variability of a cold AMO to a warm AMO.

  15. This is an interesting calculation raising important questions about the spike in whatever it is that HADCRUT4 is actually measuring. It has always surprised me that the spikes both up and down are as large as they are. After all there should be considerable inertia in the system.

    It also raises important questions about the spikes up and down from the smoothed line. If El Nino caused the spike up, what caused all of the other spikes up? And what all of the spikes down? Surely global temperature anomalies shouldn’t have the appearance of a random walk.

    Perhaps what HADCRUT4 is actually measuring is a bit like measuring the height of the bubbles above the average water level in a pot of boiling water. Or maybe the temperature of wind gusts at the end of an airport runway.

    • …about the spike in whatever it is that HADCRUT4 is actually measuring.

      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.

  16. Prof Christy in his testimony to the Senate recently said
    A series of papers appeared last year (including Huang et al. 2015 J. Climate, Karl et al.
    2015 Science) describing a new surface temperature dataset constructed by NOAA which
    indicated a bit more warming in the past 10 to 25 years than the previous versions. The
    key change dealt with seawater temperatures in the dataset now known as ERSSTv4. This
    change introduced an additional warming into the record from about 1990 onward. The
    main reason for this new warming, as the authors note, was the adjustment applied to
    buoy data, adding about +0.12 °C to the buoy readings.

    You said “We know from the linear regression that the temperature change due to Global Warming for 1 year is 0.0175 °C.”

    My question is, are the adjustments made by Karl et al reflected in the 0.0175 c /decade figure . and if so isn’t the real global warming much less ( perhaps half of 0.0175C/ year) ? Hence the record warming of 2015 is no record at all , but the result of a strong el Nino and data manipulations by Karl et al and not due to any unusual global warming caused primarily by man.

  17. There’s no doubt the El Niño that developed in 2015, which is still underway, has been abnormally strong, exceptional even.

    Rubbish. Why “no doubt”. The ’98 El Nino was an incredible spike from much lower base line. The “strength” of an El Nino event is not greater because of the higher base line temperatures, that makes it weaker. The current higher base line temps means that he part played by the El Nino event is LESS , not more.

    • But the 1998 el niño was from a higher base than the preceding el niño, and it was stronger than that one regardless.

  18. 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

      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 ..

      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

      • 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

  19. 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.

    • 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.

  20. Do we know what causes El Nino / La Nina?

    El Nino is caused by the periodic shift in wind speed and direction in the tropical eastern Pacific which leads to changes in sea Surface temperatures. In what scientists call El Niño events, prevailing easterly winds weaken or give way to westerly winds, and the normal upwelling process, which brings cool, nutrient-rich waters up from lower levels of the ocean, stops. link

    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?

    • 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.

  21. The sun’s cumulative effect is nonlinear and unpredictable outside of a limited frame of reference (i.e. scientific).

  22. 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/

      • 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. :)

      • 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.

      • Why is the 1950-1980 “baseline” more appropriate than the 1910-1945 “baseline”

        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

        According to AGW theory, …

        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.

  23. 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

  24. 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…. “

  25. 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

    • 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;

      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

  26. 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:

    April 1997   -0.063  April 1998  0.857  difference  0.920
    May 1997    0.024  May 1998   0.667  difference  0.643
    

    (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.

        Oct  2014   0.626  Oct  2015  0.811  difference  0.185
        Dec 2014   0.634  Dec 2015  1.005  difference  0.371
        

        By comparing two Decembers, you get 5%, but had you compared two Octobers the same way, you would have gotten 10%.

        If you are interested in a complete El Nino then it probably won’t fit neatly into some number of years.

        I agree with that. However doing an average of at least three months would have given a more realistic value in my opinion.

  27. 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

      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.

      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.

  28. 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.

  29. 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.

  30. 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/ :)

  31. “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.

  32. 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.

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