The climate science deniers favorite myths are about cooling. They have cooling myths about the past — see “Killing the myth of the 1970s global cooling scientific consensus.” They have cooling myths about the present (asserting that we’ve been cooling since 1998) — see “Very warm 2008 makes this the hottest decade in recorded history by far.“ And they claim that recent studies predict future cooling.
In regards the last claim, a favorite new study is “Has the climate recently shifted?” (Swanson and Tsonis, 2009). I have previously noted how absurd it is for deniers to cite that study — see New study quoted by Cato Institute deniers concludes “warming over the 21st century may well be larger than that predicted by the current generation of models.”
Now RealClimate has published a long post by Swanson, “Warming, interrupted: Much ado about natural variability.” Swanson says that we’re NOT cooling, that he never predicted we will start cooling, but that we are in for about a decade of not much warming.
That view requires believing 1) something very unusual happened in the past decade and 2) global warming is linear. Now the second assumption myth has no basis in climate science, a conclusion so obvious that I’m certain RealClimate agrees. Before addressing that myth, here is what Swanson says on the first point:
Everything hinges on the idea that something extraordinary happened to the climate system in response to the 1997/98 super-El Niño event (an idea that has its roots in the wavelet analysis by Park and Mann (2000). The figure [above] shows the spatial mean temperature over all grid boxes in the HadCRUT3 data set that have continuous monthly coverage over the 1901-2008 period. While this provides a skewed view of the global mean, as it is heavily weighted toward North America, Europe and coastal areas, unlike the global mean temperature it has the cardinal virtue of being a consistent record with respect to time. The sole exclusion in the figure is the line connecting the 1997 and 1998 temperatures.
It may well be that something unusual did happen, since something unusual seems to have happened in upper ocean warming:
Remember that figure is how Pielke Sr. justifies saying, “upper ocean warming has halted since 2003,” when one could say just as easily — and more accurately from a climatology perspective, which looks at longer term trends — “upper ocean warming has soared since 2002” (see “Roger Pielke Sr. also doesn’t understand the science of global warming — or just chooses to willfully misrepresent it“)
But Swanson’s conclusion that we will see another decade of flat temperatures is based on a very erroneous assumption. Swanson writes:
What we find is that when interannual modes of variability in the climate system have what I’ll refer to as an “episode,” shifts in the multi-decadal global mean temperature trend appear to occur….
The contentious part of our paper is that the climate system appears to have had another “episode” around the turn of the 21st century, coinciding with the much discussed “halt” in global warming. Whether or not such a halt has really occurred is of course controversial (it appears quite marked in the HadCRUT3 data, less so in GISTEMP); only time will tell if it’s real. Regardless, it’s important to note that we are not talking about global cooling, just a pause in warming.
What’s our perspective on how the climate will behave in the near future? The HadCRUT3 global mean temperature [below] shows the post-1980 warming, along with the “plateau” in global mean temperature post-1998. Also shown is a linear trend using temperatures over the period 1979-1997 (no cherry picking here; pick any trend that doesn’t include the period 1998-2008). We hypothesize that the established pre-1998 trend is the true forced warming signal, and that the climate system effectively overshot this signal in response to the 1997/98 El Niño. This overshoot is in the process of radiatively dissipating, and the climate will return to its earlier defined, greenhouse gas-forced warming signal. If this hypothesis is correct, the era of consistent record-breaking global mean temperatures will not resume until roughly 2020. Of course, this contrasts sharply with other forecasts of the climate system; the purple line roughly indicates the model-based forecast of Smith et al. (2007), suggesting with a warming of roughly 0.3 deg C over the 2005-2015 period.
Before getting to the nonsense of linear warming the above figure depicts, let me first note that while Swanson uses the Hadley Center’s data, the NASA Goddard Institute for Space Studies data is almost certainly superior (see “What exactly is polar amplification and why does it matter?“). Remember, “there are no permanent weather stations in the Arctic Ocean, the place on Earth that has been warming fastest,” as New Scientist explained (see here and here). “The UK’s Hadley Centre record simply excludes this area, whereas the NASA version assumes its surface temperature is the same as that of the nearest land-based stations.” Thus contrary to what the global warming deniers say about the recent temperature record, it is almost certainly the case that the planet has warmed up more this decade than NASA says, and especially more than the UK’s Hadley Center says.
So that’s why I see the NASA temperature record as more accurate, which puts 2005 as the warmest year on record, with a rough tie for second between 2007 and 1998. And of course that kills about half of Swanson’s theory, since it means there is little evidence we hit a plateau 10 years ago.
But what really kills his theory is the straight-line warming trend he draws from 1950 to 2030 of about 0.1°C per decade. That has no basis in climate science. As atmospheric concentrations rise, the rate of warming increases. That, of course, is how Hadley itself (!) gets total warming of 5.5°C or more by 2100, the vast majority of which occurs this century (see “Hadley Center: “Catastrophic” 5-7°C warming by 2100 on current emissions path“).
Here, for instance, is a Hadley scenario for 980 ppm and 5.5°C warming from preindustrial levels from a 2003 Geophysical Research Letters (subs. req’d) paper, “Strong carbon cycle feedbacks in a climate model with interactive CO2 and sulphate aerosols.”
Not exactly linear from 1950 to 2030 and beyond.
It is just plain odd for Swanson to base his analysis on Hadley temperature data, but then ignore Hadley’s own analysis of how temperature is likely to rise this century on the business as usual emissions path.
In fact, “Smith et al, 2007″ which Swanson plots in his figure is a Hadley (!) paper from Science: “Improved Surface Temperature Prediction for the Coming Decade from a Global Climate Model” (see “Climate Forecast: Hot — and then Very Hot“), which concluded:
Our system predicts that internal variability will partially offset the anthropogenic global warming signal for the next few years. However, climate will continue to warm, with at least half of the years after 2009 predicted to exceed the warmest year currently on record.
I’m liking that prediction more and more (see NOAA says “El Niño arrives; Expected to Persist through Winter 2009-10″ — and that means record temperatures are coming and this will be the hottest decade on record). Here’s what Hadley thinks will happen:
So, cheers to RealClimate for letting Swanson kill the myth that his paper predicts global cooling, but jeers for letting Swanson push the notion of linear warming.
And I’ll be happy to take a bet with anybody on RealClimate (or with Swanson) that Hadley is right that “at least half of the years [in the decade] after 2009 will exceed the warmest year currently on record.”
UPDATE: Tamino has a good post on this here:
I have two overriding opinions of this work. My first overall opinion is that I don’t believe it’s correct, for several reasons…. Also, the hypothesis uses certain aspects of the HadCRU temperature time series which aren’t shared by the GISS or NCDC time series, so at least in part it’s dependent on the use of a particular data set.
The paper also uses linear trend rates over 7-year intervals to suggest that the most recent lower trend rate (the suggested “plateau”) may indeed match the criteria for a “state change” of the climate, because it doesn’t coincide with a known cause (la Niña or a volcanic explosion)…..
I’m especially skeptical of the suggestion that we may be beginning an extended “plateau” of temperature change. Using GISS data, the observed variations in trend rate since 1975 (on 7-year or longer time scales) really are statistically indistinguishable from random noise, and the residuals from a straight line fit 1975-present are likewise indistinguishable from noise. Of this I’m sure: although it’s certainly possible that the climate has recently “shifted,” as yet there’s no sound statistical evidence to confirm it (nor does the paper, or the RealClimate post, claim such evidence)….
Furthermore, the trend on which they base their projection is from 1979 to 1997 (centered on 1988), which is one of the lowest 18-year trend rates in the recent GISS record. Both earlier and later time spans of the same length indicate greater warming, in particular the time span 1974 to 1992 gives a linear regression trend rate over 0.02 deg.C/yr….
Tamino provides a good figure on this.
Bottom Line: Swanson would appear to have cherry picked a very low trend rate — from 1979 to 1997 — and assumed that is a linear trend that will continue through 2020 (to 2030), in the third figure above (that I reposted from RealClimate). That is the only way he can come to the conclusion that we will see little or no warming over the next decade. That also requires ignoring the off-trend-line data since 1997 and explaining it away as an anomaly, which, again, there is little basis for doing. Finally, it requires ignoring other data (like NASA GISS), but then at the same time ignoring Hadley’s analysis of projected temps over the next two decades.
Whether Tamino is right that Swanson’s paper is important, only time will tell. But the RealClimate post is analytically very weak and based on an incredibly dubious set of assumptions.
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They claim the trend is a 1979-1997 fit, not a 1950-1997 fit. Yes, warming is nonlinear over the timeframe of a century, but it should be approximately linear over shorter time frames. That this past decade and really back to 1998 has been generally above trend may mean acceleration, a warm spell that is not indicative of the trend, or a previous cool spell that has given us a misleading trend. It has been noted elsewhere that the difference between the average of the 2000s and the 1990s is greater than the difference between the 1990s and the 1980s. How much of this do you believe is due to an acceleration in the rate of warming versus having a decade that was simply hotter than we should reasonably expect given CO2 levels due to natural variations, and what is your basis for this belief?
[JR: The figure shows an 8-decade linear trend. That's just silly. The answer to your question is that is temperature acceleration is what the science predicts, as I've shown.]
Well, Swanson does say this:
But the linearity he’s talking about here is in response to doublings of CO2, not over time. Since we’re accelerating the rate at which we’re adding CO2 to the atmosphere, the time between doublings has been and unless we get our act together will continue to shorten. This the linear response to ever-quicker doublings results in a non-linear rise in temperature when plot against time as shown in the graphs above.
Actually “ever-quicker doublings” should be stated “an accelerating approach to our first doubling”, since we haven’t actually doubled CO2 in the atmosphere over pre-industrial levels – yet. But the idea’s the same.
Over short periods of time (say 30 years) the rising trend is close enough to linear that AFAIK everyone in the field accepts that a linear fit is just fine OVER SUCH TIME PERIODS.
So I don’t see the problem with this part of what Swanson’s done.
[JR: Here's the problem. Swanson is publishing a figure with a line showing 8 decades of linear trend -- and he is claiming that the 1979 to 1997 linear trend must continue for more than another 3 decades -- yet the very data that he publishes of actual observations doesn't fit that trend, and the people whose data he is using have published multiple analyses that come up with a very different answer.]
What’s interesting about his paper is his proposal that the physical climate response to rising GHG forcing (linear in doublings of CO2, not time!) might be expressed as short-term (about three decades) of near-linear rise followed by, if you will, a “quantum jump” upwards, a short period of near-stasis, then a return to a steady near-linear rise (in the statistically significant trend, not a monotonic annual rise, of course).
Now he only gets that out of the data by focusing on one data source, HadCRUT, which in essence has been cherry-picked as he himself says. He says it’s there in the GISS dataset, too, just not as strongly expressed, so who knows? It’s interesting. It’s unfortunately been spun out of recognition by the denialist blogosphere manipulation machine, but should scientists refrain from exploring creative but possibly hare-brained ideas just because their work may be misrepresented? I don’t think so.
His work’s not been accepted in the climate science community but the reactions I’ve seen have been of the “hmm, looks wrong but – interesting!” variety.
It’s fairly clear from sea level as well that something happened in 1997-98.
http://sealevel.colorado.edu/
This coincided with my personal observation of the onset of anomalous beach erosion of low lying Bahamian sandy beaches. They seem to think that this kind of thermal ‘overshoot’ will last decades, whereas from my perspective it was restricted to a multi-year event. I believe this event represents the onset of new multi-year oceanic thermal mixing or other thermohaline events.
Meanwhile, the 1.4×10^21 kg gorilla in the room (the ocean) continues to expand. The best indicator of global heating is not air temperature but sea level. The ocean expands as it warms and takes in glacial melt. The atmosphere at 5×10^18 kg is 1/280 the mass of the ocean. If you really want to know if global heating is occuring continuously and consistently look the sea level.
http://sealevel.colorado.edu/ shows a disturbingly consistent multi-decade linear rise. It would be very difficult to deny this dataset when it rises so consistently. Why continue arguing over highly variable air temperatures (although undoubtably rising) when there is a more reliable global thermometer?
Finally, sea level is much more tangible than global average temperature. It’s easy ignore or foregt a warmer than average summer but very hard to ignore water lapping at your ankles…
dhogaza — To a fairly good approximation, anthropogenic CO2 emissions are exponential over time (since about 1800 CE). So (ln CO2) gives an approximately linear forcing and this indeed fits the data quite well rfrom 1880 CE to present:
http://bartonpaullevenson.com/Correlation.htm
(uses GISTEMP, not HadCRUTv3).
So Joe Romm is simply wrong about having (so far) an approximately linear trend in time; it is due to exponential growth in anthropogenic emissions.
[JR: Huh? I have no friggin' clue what you are claiming that I said, but what you wrote certainly doesn't disprove anything that I actually said.
To repeat, Swanson's analysis is based on the claim that the 1979 to 1997 linear trend must continue for more than another 3 decades -- yet the very data that he publishes of actual observations doesn't fit that trend, and the people whose data he is using have published multiple analyses that come up with a very different (and nonlinear) answer.]
Yes, tipping points and rapid sea level rise are just round the corner!
Joe Romm — The graph used by Kyle Swanson is the first graph in his guest commentary, not the one you copied here.
[JR: Snip. Last time I'm gonna print your nonsense unmoderated. You keep misstating what I clearly wrote and attacking it.]
I understood Joe to be talking about the *future trend* not remaining linear if we continue our business-as-usual dumping of CO2 into the atmosphere. Well, actually, not providing a good fit to a simple linear regression as we push forward projections for the next century.
You’re talking about a linear fit to the past data through the present, I agree entirely with that.
I don’t recall Tamino doing such a check on business-as-usual projections (you’re right about his work on historical data), might be an interesting thing for him to work up – how soon does the *future* projected trend accelerate to the point where a linear fit’s not good enough fer govmint werk?
Anyway, the whole thing’s a bit of a red-herring. The linearity or not of the trend over the next few decades isn’t really germane to Swanson’s argument since the article posted at RC, at least, is based on the analysis of historical data. I haven’t taken on the full paper, maybe there’s more reliance on the analysis of future projections there.
There’s one very easy attack on Swanson’s work – he has no proposed physical mechanism to explain the phenomena he thinks he’s extracted from the data, nor does anyone else …
Tamino’s take on this paper in a thread entitled “Warming, Interrupted?”
http://tamino.wordpress.com/ 2009/ 07/ 14/ warming-interrupted/
His most important comment is that the reconstructions appear to rely on aspects of HadCRUT not shared by GISTEMP or NCDC. For the aspect of applying the work to the actual climate, that is *not good*. However, he (and I) find the approach of potential significance. I’ve read both the paper’s linked in Kyle’s post; they would do well to invite Tamino to join them to do a better job of the statistics of the historical data. (And no, they don’t use any future projections.)
OK, I just skimmed the actual paper, and it doesn’t not appear to in any way depend on climate warming over the rest of the century remain a good statistical fit to a linear trend.
In fact, their paper ends with this observation, which has been ignored by the denialsphere:
In simple english, “if we’re right, current projections of warming through 2100 are too low”.
I didn’t state it strongly enough above – not only is linearity in the future trends not an assumption, but as David says, they don’t make any use of future projections in the paper.
Tamino apparently posted while I was busy babbling over here.
It’s worth reading, Joe. He doesn’t seem to think this that “{Swanson] is claiming that the 1979 to 1997 linear trend must continue for more than another 3 decades”, are you certain you didn’t read an implication into Swanson’s post that’s not really there?
To summarize Tamino (as I understand his argument) in a bit more detail than provided by David above…
[JR: As I read Tamino, I am mostly in concurrence with him.]
S & T’s understanding of the current theoretical framework for understanding the behavior of chaotic dynamical systems seems fine, but they’ve blundered in several ways in their attempt to apply that theoretical understanding to what’s happening in the real world. Despite the blundering (reliance on HadCRUT3, some statistical issues) he feels it’s important because it will help push others to do a better job (and to work on improving our theoretical understanding of such systems).
[JR: I read the paper. I am criticizing the RealClimate Post and the figure that shows the near-term conclusion (no warming through 2020) is based on extended the 1979-1997 trend through 2030 -- in spite of the fact that the data of the last 10 years is off the supposed trend and in spite of the fact that Hadley itself has published two papers that don't agree with Swanson's linear trend assumption.]
I must say that the Real Climate post is an interesting hypothesis, but the take home point is: What do our results have to do with Global Warming, i.e., the century-scale response to greenhouse gas emissions? VERY LITTLE, contrary to claims that others have made on our behalf.
It’s important to remember that almost all of the ensemble individual GCM runs have periods of around a decade of no warming, or even cooling. With the El Nino brewing all bets are off IMHO on this “slowing” continuing.
ps the point on sea level being a good indicator seems very salient to me.
NOTHING is linear except perhaps, the laws of pure math and physics. When it comes to complex systems like the relationships between species in the biosphere, the balance is easily pushed off kilter by fundamental changes in the basic structure.
Voila!
We have surpassed the tipping point for the East Coast, and are now in free fall, ecologically speaking.
I find it hard to believe this is not reflected elsewhere.
Sorry, but it is time to start speaking of survival.
Swanson published: http://www.uwm.edu/ ~kswanson/ publications/ 2008GL037022_all.pdf and a quote:
“These (124) shifts were accompanied by breaks in the global mean temperature trend with respect to (125) time, presumably associated with either discontinuities in the global radiative budget due (126) to the global reorganization of clouds and water vapor or dramatic changes in the uptake (127) of heat by the deep ocean.”
And then in his post over at Realclimate: “What do our results have to do with Global Warming, i.e., the century-scale response to greenhouse gas emissions? VERY LITTLE, contrary to claims that others have made on our behalf.”
What am I not getting here?
None of this changes our understanding of climate sensitivity.
#5 Paul M. says:
“Yes, tipping points and rapid sea level rise are just round the corner!”
Are we crying wolf again?
#12 Gail says:
“NOTHING is linear except perhaps, the laws of pure math and physics. When it comes to complex systems like the relationships between species in the biosphere, the balance is easily pushed off kilter by fundamental changes in the basic structure.”
This is basically rubbish. Biological systems have a great capacity for adaptation even when severe perturbations occur. A statement like “fundamental changes in the basic structure” are meaningless.Ecological systems may appear to be stable but this is fundamentally wrong. Systems are always in flux but it is just the time frame that can make them appear to be stable. Despite the level of perturbation, ecological systems will adjust and shift to new structural compositions.
#14 Richard Steckis, I doubt it.
There are many pros who think so, some privately and a few publicly.
Empirical data, both now and historically support this.
We are basically trying to do the best we can, within the probabilities. Nothing is certain. What is close though is that all our projection have been underestimates.
Well, yes and no, One possibility is that warming will be WORSE than current physical-based models predict.
That’s a take-away point from their work … things might rebound much more than predicted by mainstream climatology.
They aren’t talking about the biological response to a physical change.
They’re talking about a physical change.
So why don’t you STFU until some competent population ecology people explore what the biological response might be?
This is basically rubbish. Biological systems have a great capacity for adaptation even when severe perturbations occur. A statement like “fundamental changes in the basic structure” are meaningless.Ecological systems may appear to be stable but this is fundamentally wrong. Systems are always in flux but it is just the time frame that can make them appear to be stable. Despite the level of perturbation, ecological systems will adjust and shift to new structural compositions.
This would be compelling if you brought up resilience. Since you did not, it is wrong.
Best,
D
dhogaza #18
“…great capacity for adaptation…” might mean secure airline tickets in the back pocket.
“Biological systems have a great capacity for adaptation even when severe perturbations occur.”
True, in a long term way like say, the replacement of dinosaurs with mammals (and similar shifts in the plant kingdom). But the term “mass extinction” isn’t just made up. It refers to real events – “severe perturbations” if you will. So sure, eventually both the plant and animal kingdoms will recover from whatever max CO2 humans impose. The number of humans (and what sort(s) of civilization) that survive 1000 ppm CO2, … well, that’s not so guaranteed.
Sarah Palin is a) evil and b) a fraud – no way she wrote this:
http://www.washingtonpost.com/ wp-dyn/ content/ article/ 2009/ 07/ 13/ AR2009071302852.html
regarding the Palin WP “contribution”… Note that she frames ACES as an “energy” cap&trade plan… Uh, no… the cap&trade is on “carbon” Sarah, not energy… And, not surprising, environment and climate do not surface in the piece whatsoever… Thank god this loon is not in government at any level at this point… even as mayor of Wasilla. And this from a Canadian.
At the end of the day, there’s a simple word for what Swanson has done with the data: cherry picking.
You can truncate, manipulate and otherwise torture the data to support a forgone a conclusion, but it doesn’t make it valid.
Bottom line: if you cite something or use it as a basis for a conclusion, you can’t ignore the part you don’t like or that doesn’t support your bias.
And dhogaza, I don’t know what your point(s) is (are) but that’s what Swanson’s done. Period.
Gov. (11 more days) Palin’s article is downright Orwellian. But there’s one sentence in it with which I agree completely: “Those who understand the issue know we can meet our energy needs and environmental challenges without destroying America’s economy.”
Good critique, although I think the Hadcrut vs Gistemp difference, while noticeable, isn’t that dramatic. I would also add that the paper seems to ignore the impact of the solar cycle, positive solar forcing and volcanic activity lull early century, and mid-century sulfate aerosol and volcanic cooling impacts, which might lead one to overestimate the impact of ocean cycles.
I’m not personally convinced of the Swanson paper (it’s in contrast to most other estimates) but I believe it to be a serious effort done in good faith.
Water on Earth has the potential to hold a fair amount of heat, but the air holds very little heat.
Measuring the global warming by looking at air temperature is like weighing your dog by putting his tail on a postage scale, and then estimating your dog’s total weight from number on the scale. Any number you get for your dog’s total weight is not going to be very accurate. So, we apply statistics to the numbers and argue about them. (My dog’s tail is stronger than your dog’s!)
“The Earth has been cooling since ????” completely ignores the heat that went into melting a lot of Arctic Sea ice. Swanson does not address ice. Just because the heat is not in the air does not mean that the Earth has not warmed. Melting ice is ongoing global warming even if the air temperature does not change.
Somebody will say that it is more heat than can be accounted for with a bit of sea ice. If you look, I think you will find that we are also missing a bit of permafrost, some ice shelves, glaciers, and some anchor ice.
Moreover, ice events remind us that global warming is not linear.
Best comment yet, Aaron, and an excellent metaphor, though testing your thesis I received a number of dog bites and am banned from using the scales again at my local post office.
The linearity in Swanson and Tsonis clearly and explicitly refers to the period 1977 to 1997. It explicitly excludes the start and end points of global climate shifts – the 1976/1977 Pacific Climate Shift and the global climate shift that occured in 2001/2002. NASA put it at 2008 – but, really, the biology says different.
[JR: No. They project that linearity through at least 2020 (and 2030 in the RealClimate figure) in order to make their claim that there will be no substantial warming over the next decade.]
That these are real is not in any doubt in the world of oceanography, hydrology or fisheries biology. The exclusion of climate jumps in 1976 and 1998 is a deliberate exclusion of natural climate shifts from the underlying CO2 trend.
The residual trend is calculated in the same way as the 0.2 degrees/decade increase calculted by the IPCC – except with different end points. The 0.1 degree/decade trend in Swanson and Tsonis is simply the trend on an interval that excludes 1976 and 1998. Points that are not arbitrary but based on an understanding of multidecadal climate shifts that are not random and are evident everywhere in the climate record.
Despite Swansons understandable prevarication – the climate sensitivity for a 0.1 degree trend would seem to be less than the sensitivity represented by a 0.2 degree trend.
There are 2 possibilities – the 20 to 30 year climate shifts are caused by an internal dynamic process. In which case there is no loss of heat from the ocean/atmosphere system – it simply redistributes. From the ocean to the atmosphere in a warm phase and from the atmosphere to the ocean in cool phases. Much as heat is transferred from the ocean in an El Niño and to the ocean in La Niña.
The other possibility is that it is caused by something (like clouds) that changes the actual radiative balance of the planet.
I would definitely opt for clouds at this point – both low and high cloud in the climatically importent equatorial zone declined to 1998 and have increased since. The change in shortwave forcing calculated by the guys at Project Earthshine is -2W/m2 since 1998 – climatically significant.
Neither ocean or atmosphere temperatures are trending anywhere currently. I have done the calculation for the enthalpy of fusion based on recent mass increases in the oceans – and it is not nearly sufficient to account for the missing heat that should, according to the theory, be there.
To have a look at your assumptions that the global warming hiatus requires believing 1) something very unusual happened in the past decade and 2) global warming is linear.
The claim is that these ‘unusual’ events happened around 1910, the mid 1940’s, the mid 1970’s and 2001/2002. It is not unusual at all and is very evident in fisheries, hydrologic and oceanographic science.
I believe that what is being claimed is climate episodes of 20 to 30 year duration. This is far from a claim that climate is linear. You have had a quick look at the graph and jumped to wrong conclusions. I am sure it is not your fault – you just need a broader education. If the climate shifts are not evident statistically – and I believe they are – then look at the physical science.
Swanson and Tsonis talk about natural variability – and you speak about random variation. There is nothing random in climate – only processes we don’t understand. The difference is that Swanson and Tsonis understand a little better the physical environment.
Statistics suggest that a cool mode of the PDO is associated with less intense and frequent El Niño and more frequent and intense La Niña. A change over a couple of decades in the frequency of ENSO. This is just one element of multidecadal climate shifts – but it suggests that you shouldn’t hold your breath waiting for a big El Niño to turn things around.
[JR: I've offered a bet that says otherwise. No takers so far.]