Falsifying projections from WUWT

It is becoming less fashionable to deny climate science these days. As the Paris meeting approaches, more deniers are shifting a tad away from the extreme end of denial. Even James Inhofe, one of the extremist fake sceptics in the USA, favourably quoted Dr James Hansen in a recent op-ed piece promoting nuclear power as a way to reduce emissions.

Anthony Watts at WUWT if anything has shifted toward, not away from, extremist denial. Every now and again he'll publish an article in which a person claims to accept global warming - to a point. That point being that they don't accept that it has or will warm as much as has and will.

Today he's allowed an article from one such science denier, Richard J. Petschauer (archived here). I think he's trying to portray himself as a "reasonable person", though his ideas aren't reasonable at all.

He's acting as if one can be "a little bit pregnant" - when you can't. You're either pregnant or not. He's not. Nor is he accepting of science. The world has warmed by almost 0.7°C since the middle of last century, and it is "extremely likely" (>95%) that it is human actions that have been the dominant cause of this warming. Despite this, Richard claims that he doesn't "believe" that climate sensitivity is in the range that scientists have found it to be: temperature will rise from between 1.5°C and 4.5°C with a doubling of CO2. Instead he wants to "believe" that:

...a warming from double CO2 in a range of 0.6 to 0.9 C
... About 1 C warming in the next 140 years does not seem to be a problem.

But look. CO2 has increased by 40% at 400 ppm. It's not doubled to 560 ppm (yet), and the world is already almost 0.7°C warmer than it was in the middle of last century. And it's almost one degree warmer than it was before industrialisation. Therefore Richard is already proven wrong.

He can mutter about feedbacks and emissions to his hearts content. However the way we are going his one degree rise in 140 years will be four, five or six degrees in 140 years if he and his fake sceptic mates have their way. No-one will thank them.

Richard uses the royal "we" in his article. "We believe the complex computer models overestimation of warming is mostly based on a combinations of three factors: overestimating positive water vapor feedback, underestimating negative feedback from increased sea surface evaporation and treating cloud feedback as positive feedback while it is very likely negative."

He is engaged in motivated reasoning. I doubt there'll be much negative feedback from evaporating sea water - water condenses again after all, releasing heat and falling as rain, hail or snow. There's some extra accumulating in the air but not enough to make a huge difference. In any case, more water vapour in the air makes it still warmer. Water vapour is a strong greenhouse gas.

Richard gives no reason for his cloud feedback being "very likely negative" apart from saying there will be more clouds. He doesn't mention that some clouds are  a positive feedback (high altitude clouds) and some are negative (low level clouds).  The science indicates it is likely to be positive on balance. It could be line-ball - making little difference. Less ice and snow cover is definitely a positive feedback.

Projections and Predictions

There are quite a number of other "wrong" statements in the comments. One thing I noticed in among the ignorant comments was one from Terry Oldberg, who like many other deniers, promotes his ignorance of climate model projections. He thinks they can't be falsified. He's wrong. They can be. Terry Oldberg wrote:

April 25, 2015 at 10:18 pm
The author states that “data shows global temperatures have increased much less than models predicted” but in a post to the blog of the journal “Nature”(circa 2007) the climatologist Kevin Trenberth insists that the models do not predict. According to Trenberth, they “project.”

For a distinction to be made between a prediction and a projection is important because: a) a prediction is falsifiable but a projection is not and b) predictions convey information to policy makers about the outcomes from their policy decisions but projections convey no such information. Predictions would make it possible for governments to exert a degree of control over the climate but the climate models of today make projections and these do not support control. Governments think they can exert a degree of control as a result of conflation of “prediction” with “projection” by people who include our author.

Terry is wrong on this as he is on so many other things. He doesn't understand why climate projections are called projections. I'd say he doesn't understand why economic projections are called projections either. It's because there can be different estimates for different sets of conceivable circumstances. There's more than one projection, so they aren't a single prediction.

Climate models are developed to determine what will happen to earth under different conditions. For the IPCC reports, standard sets of conditions were developed, using Integrated Assessment Models. These sets of conditions are called Representative Concentration Pathways, or RCPs. They allow for differences in the path we take in the future - different emissions trajectories, different economic trajectories etc. The most advisable of these pathways has the lowest number - RCP2.6, and would require that we drop emissions by 70% fairly quickly. (Many people think this goal is already unattainable.) At the other end of the spectrum is RCP8.5. That's the one we are tracking now, or maybe even exceeding. Projections on this pathway lead to a warming of between about four and six degrees Celsius by the end of this century, and it won't stop there.

The chart below illustrates the different projections for different choices we make. Notice that the chart is showing the increase over the temperature in 2000, not the pre-industrial temperature. And it's showing the mean over 2081 to 2100, not the actual projection for the year 2100:

Figure SPM.6 | Global average surface temperature change (a) ... as determined by multi-model simulations. All changes are relative to 1986–2005. Time series of projections and a measure of uncertainty (shading) are shown for scenarios RCP2.6 (blue) and RCP8.5 (red). The mean and associated uncertainties averaged over 2081–2100 are given for all RCP scenarios as coloured vertical bars at the right hand side of each panel. The number of Coupled Model Intercomparison Project Phase 5 (CMIP5) models used to calculate the multi-model mean is indicated.

What that chart shows is two projections. They can be falsified. If we follow a similar pathway as one of those projections in terms of emissions, and it turns out that the surface temperature is way above or way below the range specified, then the projection will be shown to be wrong. Just as Terry Oldberg and Richard J. Petschauer have been shown to be wrong.

From the WUWT comments

A lot of WUWT deniers were quite upset that Anthony allowed an article by someone who accepts the greenhouse effect - or accepts a little bit of it.

Patrick is a greenhouse effect denier, not a temperature denier. He doesn't say what he "believes" has caused global warming.

April 25, 2015 at 12:09 pm
As a first post, it is my understanding that no skeptic suggests (I won’t use the word believe) there has been no global warming. It’s a fact; the globe HAS warmed. The point in contention is what is DRIVING that warming. So far we see CO2 is not *THE* driver. Only computer models suggest that. Actual evidence suggests otherwise.

Leo Smth is another greenhouse effect denier, saying that water vapour feedback is negative - the opposite to reality.

April 25, 2015 at 11:46 pm
I think you are overly pedantic here:
I see nothing wrong in the implicit “IF this model were the truth, the whole truth and nothing but the truth THEN” ….the result of these changes indicates a warming from double CO2 in a range of 0.6 to 0.9 C, much less than IPCC’s value of 1.5 to 4.5 C…
Personally I am of the opinion that water feedback is quite strongly negative, and the changes will be even less than that.

ferdberple decides to argue over the meaning of words. Not sure why. Perhaps he just wants to air his "thoughts" and couldn't "think" of anything much to write.

April 25, 2015 at 7:08 pm
What is the scientific definition of climate skeptic and global warming?
When you say “global warming” do you mean made made global warming or all warming? Do you include only the effects of CO2, or all man made effects?
How can this be science without precise, agreed definitions of terms? Imagine that we didn’t agree on the length of a meter? We would be arguing all day over distance. 

AB mistakenly thinks "we have only recently discovered" something. He's wrong. CO2 is not just a well-mixed greenhouse gas - it is a very well-mixed greenhouse gas. Much, much better mixed than water vapour.

April 25, 2015 at 7:02 pm
More a comment to the replies above mine and that is, haven’t we only recently discovered that co2 is far from evenly mixed in the atmosphere?
Is this factored into any of the calculations/models?
Questions from a total amateur. 

Allen63 is quite pleased that he has found another person who has the same motivated thinking as he does, and rejects science. He now sleeps easily at night, believing that they both must be right, and 99.999% of all science must be wrong.

April 25, 2015 at 12:20 pm
Nice summary. Pretty much what I believe. But, I have not done all the math myself — and may be wrong about part of it. Even so, CAGW does not seem to be a likely problem, to me.

ladylifegrows believes that CO2, being heavy, falls to the surface! In the same paragraph he or she talks about much heavier water droplets aggregating very high up in the atmosphere!

April 25, 2015 at 4:12 pm
One reason is that the air is much thinner in the upper atmosphere where the reflection of incoming solar occurs. The “trapping” of heat occurs in the lower layers. BTW, the CO2 molecule is heavier than N2 and O2, which are 99% of the atmosphere. Therefore, it is somewhat more concentrated near the surface. 

There are lots and lots of conspiracy theorists on the thread as usual. For example, knr, who intertwines fraud, career advancement, and fudgery:

April 25, 2015 at 3:59 pm
Do not underemphasis that the ‘right results ‘ from these models can make a real difference to those driving them and their careers . And so given the models ‘only’ do what they are told , you can see how the selection of what you tell them can be subject to the need for the ‘right results ‘
And when tweaking a few parameters takes minutes and models runs hours at most , it is not even a hard thing to do to run a few ‘versions’ until the ‘right results’ pop out. 

A lot of deniers wrongly think that it's fake skeptics who discovered the urban heat island effect. They wouldn't know about it if the scientists hadn't told them. Scientists adjust for it, and then the fake sceptics complain because the data is "adjusted". It's deniers who are the "crazy". Menicholas:

April 25, 2015 at 2:36 pm
“Urban heat islands are a measurable fact.”
How this is even in dispute is a Twilight Zone crazy! 

God-botherer Janice Moore has been quiet on her God-bothering lately, but sets the record straight about WUWT deniers:

April 25, 2015 at 1:17 pm
Mr. Petschauer, It is one thing for you to assert your belief that CO2 causes the temperature of the earth to rise. It is quite another to mischaracterize MANY (I believe it is most, but will not assert that here, having no solid proof…) of us science realists who firmly disagree with you.

1. You: “There are many areas where most skeptics and the “alarmists”, as they are called, agree. First is the idea of “climate sensitivity”, a useful benchmark for making estimates. It is the final average global temperature rise that would be caused by a doubling of the carbon dioxide (CO2) in the atmosphere, assuming there are no natural changes. Second, most agree on well established methods to estimate how greenhouse gases absorb and emit heat, … .”

Science Realists:
1) Only in highly controlled laboratory conditions HIGHLY UNLIKE the climate system called “earth,” has CO2 exhibited any significant warming potential.
2) Never has CO2 been proven to cause any warming on earth at all. And, so far, the evidence points against it (CO2 UP. WARMING STOPPED.).
3) There is good evidence (See Dr. Murry Salby, for instance) that CO2 increase lags temperature increase on earth by a quarter cycle.
*******************************************************************

2. “We believe … .” No, Mr. Petschauer, YOU believe — and many others, no doubt, also believe as you do about CO2 — but, not “most” (as you brazenly and inaccurately assert).
*************************************************

CAVEAT TO ALL READERS: Richard Petschauer does NOT represent the views of MANY of us science realists on WUWT, we who:
1. Believe the earth is cooling overall, since about 6,000 years ago (at least);
2. Believe the earth warmed after the end of the “Little Ice Age;”
3. KNOW CO2 has never been proven to have caused any warming on earth; and
4. Believe the temperature of the earth has been flat or is slightly decreasing for over 18 YEARS, now. 

Janice gets lots and lots of applause from the rabble. How dare someone come into their science illiterati club and lecture hard core deniers about what they believe! Even if he's writing nonsense. Quite a few of them quote David "funny sunny" Archibald who said that CO2 hardly causes any warming. He's the chap who thinks that within five years, by 2020, earth will be way colder than it's been in the entire Holocene - that the temperature will plunge by 1.5 degrees!


Well, well, well...After getting lots of flak, the guest essayist responded, but his comment was snipped by the mod. I wonder what he wrote? Richard Petschauer

April 25, 2015 at 2:17 pm
(Snip. -mod.) 

This might be part of it, as quoted by Joe Born. What's the bet the mod was Smokey?

April 25, 2015 at 3:14 pm
“So called “deniers” are giving us skeptics a bad image.

I would say that the number of alarmists saying transcendently silly things greatly exceeds that of skeptics doing so. But that is no reason not to call out people on “our side,” too, when they make bad arguments, and I’m afraid that on this site we tend to give the more-prominent clowns a pass.
We should be keeping everyone’s feet to the fire. 

I'll finish with nc, who has a plea that no-one at WUWT will respond to:

April 26, 2015 at 12:51 am
Hello, will someone, someday please differentiate between natural and man made C02 in all this so called warming gobbledygook and separate the effects?

This is for you, nc, courtesy of scientists, with my highlights. Nature doesn't care whether the CO2 comes from burning fossil fuels, cutting down trees or from natural rather than human processes. All that matters is how much of it is in the air. We control that:

Figure SPM.3 | Assessed likely ranges (whiskers) and their mid-points (bars) for warming trends over the 1951–2010 period from well-mixed greenhouse gases, other anthropogenic forcings (including the cooling effect of aerosols and the effect of land use change), combined anthropogenic forcings, natural forcings and natural internal climate variability (which is the element of climate variability that arises spontaneously within the climate system even in the absence of forcings). The observed surface temperature change is shown in black, with the 5 to 95% uncertainty range due to observational uncertainty. The attributed warming ranges (colours) are based on observations combined with climate model simulations, in order to estimate the contribution of an individual external forcing to the observed warming. The contribution from the combined anthropogenic forcings can be estimated with less uncertainty than the contributions from greenhouse gases and from other anthropogenic forcings separately. This is because these two contributions partially compensate, resulting in a combined signal that is better constrained by observations. Source: IPCC SPM AR5

Figure 10.1: (a) is anthropogenic and natural forcings (b) is natural forcings only. Source IPCC AR5 WG1.