Renowden has no evidence for CAGW

Jo Nova's take on the lack of evidence for AGW

This is in response (slightly delayed by an Easter break) to the list of “proofs” produced by Gareth Renowden, at Hot Topic, in answer to my request of Sir Peter Gluckman, the PM’s scientific advisor, for evidence of a human cause for anticipated dangerous climate change, more properly referred to as the catastrophic anthropogenic global warming (CAGW) theory.

On 17th April, I wrote:

I would remind Sir Peter that evidence is required to establish the following key factors in the global warming debate — evidence that has not surfaced so far. We have been looking for evidence to show:

1. The existence of a current unprecedented global warming trend.
2. That the greenhouse effect is powerful enough to endanger the environment.
3. A causal link between human activities and dangerously high global temperatures.
4. That climate models have a high level of skill in predicting the climate.
5. A causal link between atmospheric levels of carbon dioxide and global temperatures.
6. A causal link between global warming and the gentle rise in sea level.

In response to this, Gareth claims “there is plenty of evidence to address every one of his points” and presents some attractive and interesting graphics in support. I’ll comment on what he says to each point.

1. The existence of a current unprecedented global warming trend.

GR: “…is [the current warming] unprecedented…? Well, no.”

This is most unexpected from the foremost warmist blogger in the country. No comment by me could improve his answer, because he agrees with me unequivocally. I will simply point out that his dark reference to past “major extinction events” is mere arm-waving. The lack of evidence for any current abnormal warming is, by itself, fatal to the whole CAGW theory, because it means that all the CO2 which humanity has “spewed” into the atmosphere over the last 70 years or so has had no undue effect on the temperature. Why then should we believe the forecasts of doom?

Note that Renowden mentions “pedants”, claiming that only they would consider it important whether the warming was “unprecedented.” But, of course, any reasonable person would want to know whether the recent warming was unusual.

2. That the greenhouse effect is powerful enough to endanger the environment.

GR: “The greenhouse effect is powerful enough to deliver the environment we live in, by retaining enough heat to lift surface temperature by about 33ºK.”

I must agree with that summary, as it seems to be widely agreed, although it is certainly disputed, and not settled science. But it includes all of the so-called greenhouse gases, not just CO2. Carbon dioxide contributes a paltry 4% or so of the total natural greenhouse effect, with the man-made portion coming to about 0.1%. Although the exact amount is controversial, it is undisputed that water vapour induces a hugely greater warming than CO2 does. So the “greenhouse effect” raises the temperature, but Renowden gives no evidence for a dangerous temperature rise from our CO2 emissions — and considering the logarithmically declining response of temperature to increasing CO2, it’s impossible. He agrees with the usefulness of CO2 in producing our current environment, which I strongly endorse, but he gives no evidence for dangerous warming.

That’s two down, only four to go. Score: CCG – 2, GR – 0.

3. A causal link between human activities and dangerously high global temperatures.

GR provides this graphic from Sceptical Science:

human fingerprints on global warming

This is highly diverting but of little relevance. “Less heat escaping to space” and “More heat returning to Earth” are directly relevant to the greenhouse effect, but not to a human influence, however, both points have been disproved by Spencer and Lindzen.

The remaining points prove nothing of a human influence. Some are evidence of warming, but not of its cause. The whole thing looks like a simplistic rehash of Trenberth’s attempt at an energy balance. Where are nights warming faster than days? (Not that it shows a human influence anyway.) What is the evidence for a lower level of atmospheric oxygen and how does it show a human influence?

Score: CCG – 3, GR – 0.

4. That climate models have a high level of skill in predicting the climate.

GR claims the models do “pretty well” but then asks: “do you really want to risk waiting a decade or two to see how current models perform? Doesn’t strike me as wise, given 1. and 2. above…”

“Pretty well?” Would you engage a brain surgeon who had done “pretty well” in his final exams? Would you commit the nation to spending billions of dollars based on forecasts that are “pretty well” accurate? Would you require only “pretty good” engineering assessments before commissioning foreshore protection works? This is a nonsense, and Gareth knows it. We don’t need absolute certainty, but we sure as hell demand better standards for our public policy than “does pretty well”!

Climate models actually don’t do very well without a blizzard of fudge factors to account for such things as aerosols during the 1950s and 1960s, when temperatures were dropping, the effects of clouds and even the greenhouse effect itself. In other words, they don’t do everything from first principles, not by a long shot. The models failed to predict the recent fall in ocean heat content, they cannot predict the great ENSO ocean fluctuations that strongly influence global temperatures, they are programmed to believe that low-level clouds cause warming, while real-world observations show they cause cooling, and they predicted that global temperatures for the last 15 years would rise, when in fact they have been in stasis or mild decline.

I guess you could say that, apart from that, they do work “pretty well.”

Since Gareth failed to score on points 1 and 2 above, his argument that it “doesn’t strike me as wise, given 1 and 2 above…” fails, too, as it relies on them. If models performed skilfully in hind-casting global temperatures, we wouldn’t have to wait to verify them, but they fail. One of the reasons for their failure is our low level of scientific understanding of the climate, which is acknowledged by the IPCC, though not widely publicised. The models aren’t magic, they echo scientific understanding at every point and where that is deficient the models are crippled and lose touch with reality.

All the climate models consistently predict a “hot-spot” in the upper troposphere which is just as consistently missing in real-world observations. This shows the lack of skill of the models and allows us to dismiss them as reliable indicators of future climate.

To illustrate this, here’s a graphic which David Evans kindly offered, taken from data in the IPCC AR4, 2007. The original is available at Jo Nova’s web site.

missing tropospheric hotspot

Score: CCG – 4, GR – 0.

5. A causal link between atmospheric levels of carbon dioxide and global temperatures.

GR: “Treadgold’s blockhead moment.”

Actually, I agree to the extent that my point was loosely phrased, and Gareth took full advantage. I was looking for evidence of a correlation between atmospheric levels of carbon dioxide and global temperatures. Gareth simply referred to the (disputed) greenhouse theory but cannot be faulted for omitting to quantify it, because I didn’t ask him to.

But he is wrong to state: “More CO2 means more heat retained in the system, or the greenhouse effect he seems to admit exists wouldn’t. That’s about as clear a link as you can get.”

That’s an incorrect characterisation of the process, as little further significant heat can be caused by further increases in atmospheric carbon dioxide, because the temperature response to CO2 is logarithmic. Gareth should know this. For each new portion of CO2 added to the atmosphere, less and less is added to the temperature. This doesn’t invalidate the greenhouse effect itself, even though Gareth says it does. It is a link, but it cannot lead to dangerous temperatures from mankind’s emissions.

But, because I mis-stated the question, I’ll have to give him the point. Score: CCG – 4, GR – 1.

6. A causal link between global warming and the gentle rise in sea level.

GR: “More basic physics that seems to have eluded Treadgold. If you warm up water, like most things it expands. Thermal expansion has been (until recently) the single biggest contributor to sea level rise and will continue to play a big part until the oceans reach thermal equilibrium — and that will take hundreds of years, even if we do manage to end our binge on fossil carbon.”

Thanks for the explanation, Gareth.

My question was faulty; by “global warming” I meant “anthropogenic global warming.” I want evidence that that part of global warming caused by mankind (if such a part exists) has caused any part of the gentle rise in sea levels observed for several hundred years.

There is no such evidence, because there is no evidence of a human contribution to global warming, and no warming at all since around the turn of this century.

The March, 2011, Washington Post story he references concerns a paper reporting up to another six inches (150 mm) of sea level rise by 2100 to be caused by the “vast ice sheets of Greenland and Antarctica.”

Six inches does not concern people of ordinary nervous systems. But they claim the ice sheets “are melting faster than previously estimated and that melting is accelerating.”

The paper does not measure the outflow of melted ice (an impossible task), so we don’t even know that ice actually melted. It becomes vital to know why the ice sheets are diminishing. It does not have to be rising atmospheric temperatures — it is highly likely to be diminished snowfall.

Diminishing glaciers are not necessarily evidence of increasing temperature. As this story is not evidence of global warming, it cannot be testament to a link between that and sea level rise.

Score: CCG – 5, GR – 1.

Bad luck, Gareth, you lose.

Whatever Mr Renowden might say about my personal motivations and expertise, he must at some point address what I say about the lack of evidence, which is far more significant — especially points 1–4: there is no unprecedented warming trend, no potentially dangerous greenhouse effect, no proof we’re causing dangerously high temperatures, and no evidence of climate model skill.

Perhaps Gareth’s friends in NIWA might give him a hand with this? He claims there’s evidence but has not disclosed any. I still don’t believe it exists.

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Huub Bakker
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Huub Bakker

On question 2: Actually Richard, as I understand it, this is a popular piece of misinformation. The greenhouse effect has nothing to do with the “33K” increase in temperature. It relies upon the idea that the Earth would be 33C cooler if the atmosphere were not there. However, it is the compressive effect of the gases in the atmosphere that produce this increase. It is responsible for the ‘adiabatic lapse rate’ that shows temperatures declining as you go upwards to lower and lower pressures. This is why Venus is so much hotter than the Earth (apart from being closer to the sun); it has 40 times the atmospheric pressure at the surface. If it was a greenhouse gas effect then Venus would be much hotter still because of its high concentration of carbon dioxide and water vapour. So too would Mars, which is 90-something percent carbon dioxide. The case can be argued the other way too. According to the same argument (that there is a 33C increase in temperature due to the greenhouse effect) the Moon can be shown to have a greenhouse effect because its day and nighttime temperatures are not as… Read more »

Richard Treadgold
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Yes, I agree. I just thought I’d take advantage of his statement in other ways and avoid an essentially distracting argument.

Thanks for the description of the “compressive effect.” First time I’ve heard it.

Huub Bakker
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Huub Bakker

Actually, the lapse rate (decrease in temperature with height) is caused by the ‘well-known’ thermodynamic principle that gases heat up when compressed and cool down when they expand. This is what happens as gases circulate vertically due to being heated by the ground etc; as they ascend and expand, they cool down. Having given up their heat high in the atmosphere they descend and are heated. This means that circulation will maintain a temperature profile, the lapse rate, solely because of the difference in pressure.

Therefore, saying that the difference in temperature between an Earth without an atmosphere and one with an atmosphere is solely due to greenhouse gases, and that this is 33C, is nonsense.

Anthropogenic Global Cooling
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Anthropogenic Global Cooling

When faced with the irrefutable truth over how faulty the AGW hypothesis has proven to be, and how little evidence there is for it, the anthropogenic global warmer will look to find some way of undermining you on personal level. Failing that they will put their head in the sand and outright lie. Ken Perrot was the best one for this, ignore all the glaringly obvious evidence disputing AGW and making a personal attack, all the while failing to address ANY of the fatal flaws in AGW

Warming is not a sign of anthropogenic induced warming, and what little effect CO2 does have is so minimal as to be largely irrelevant. Without the assumed feedbacks that have failed to eventuate, AGW theory is baseless. Some people just can’t admit they’re wrong, I only wish they’d do it with their own wallet instead of mine.

Richard Treadgold
Guest

“do it with their own wallet” — I can’t agree more. That’s what Kiwis don’t seem to get yet.

Richard C (NZ)
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Richard C (NZ)

GR’s “clear” link is:- “More CO2 means more heat retained in the system” An explanation by Gareth of the thermodynamic mechanism of the “clear” “link” at a molecular level would be helpful (shouldn’t be difficult because it’s “clear”). Having done that, he could give his clause considerable credibility by informing the world where exactly “more” heat is being “retained in the system” (i.e. the empirical proof). The location would be very helpful to Kevin Trenberth given his difficulty in tracking it down (inadequate observing systems apparently). Puckerclust at least had a go at the “Physics Facts” but all he got for his efforts was an inevitable slapping – your turn now Gareth. To help you avoid Puckerclust’s pitfalls, here’s the chronicle of his demise:- http://climatechangedispatch.com/home/8931-ten-physics-facts-setting-the-record-straight PHYSICS FACT #1: The atmospheric carbon dioxide concentration has increased rapidly since the beginning of the industrial revolution, after being nearly constant for thousands of years. FACT: If the “beginning of the industrial revolution” is defined as mid-18th century, this is NOT true. There are published measurements of aerial concentration of CO2 above 400 ppmv in the 1800s. A further illustration of the variability of atmospheric carbon dioxide… Read more »

Mike Jowsey
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Mike Jowsey

This is a very inspired article RC – thanks for the link. Worth reading the original, along with the comments. (esp. Gator)

Richard C (NZ)
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Richard C (NZ)

Naomi Oreskes says it’s “simple”:- “The reason is simple: conservation of energy. If you trap more energy in the atmosphere, it has to go somewhere, and one of the places it goes into is weather.” Great, now we’re getting somewhere. Some of the “missing heat” has gone “into” the weather, where’s the rest gone? Her evidence for CAGW (from the CAGW straw clutchers grab-bag – just make it up as you go along):- The harms of global warming will unfold over the next several decades and we do not know exactly what form that will take. But there are already plenty of signs. Spring is coming earlier than it used to. Rivers and lakes are warming. Glaciers are shrinking, while glacial lakes are expanding. Permafrost is becoming unstable. Plants and animals are shifting their ranges upwards in terms of both latitude and elevation. Oreskes also says there is a credible argument that people are beginning to die from extreme weather events that are probably linked to climate change. In her foreword to Haydn Washington’s and John Cook’s Climate Change Denial, Oreskes points to the Queensland floods – how some commentators were willing to… Read more »

Mike Jowsey
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Mike Jowsey

Yes, I was particularly amazed at the statistic that 68% of women think that tsunamis are a result of global warming (question 4.b). And I thought girls were meant to be smarter than me.

Mike Jowsey
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Mike Jowsey

I’m obviously too gullible 😉

Andy
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Andy

I am quite surprised too at GR’s comments that the warming is not unprecedented. The only real evidence for this is the Hockey Stick graph. Is this now discredited? Surely not!

Clarence
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Clarence

Well, even Gareth had his legs whipped out from under him by the admission of Prof Phil Jones (on the BBC) that the Mann & Briffa Hockey Sticks had insufficient evidence of what was happening in the Southern Hemisphere during the Medieval Warming Period.

This statement was very influential as it was made with legal and PR advice, in response to a question on written notice, at a time when Jones was nervous about the pending enquiries into CRU conduct.

Mike Jowsey
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Mike Jowsey

Surely not the HHS!!! (Holy Hockey Schtick). But, wait – what’s this? OH Noes!!

Andy
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Andy

Surely we can distill the argument down to these viewpoints:

(1) The greenhouse effect theory is wrong. The entire AGW theory rests on this and therefore is wrong.

(2) The basic greenhouse effect is right. Feedbacks are negligible and possibly negative. Ergo, there is nothing to worry about

(3) The basic greenhouse effect is right..Feedbacks are positive. There will be significant warming, but it will not be catastrophic.

(4) The basic greenhouse effect is right..Feedbacks are positive. There will be significant warming, and this will cause “runaway warming” that will have a catastrophic effect on the world’s climate system

We can argue until the cows comes home about tornadoes, ice sheets, etc etc. Surely we can focus on these viewpoints and present the case for each point of view?

Richard C (NZ)
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Richard C (NZ)

I prefer that the argument is distilled even further to remove the latitude for erroneous over simplification e.g. Renowden’s “More CO2 means more heat retained in the system”, Oreskes’ “If you trap more energy in the atmosphere, it has to go somewhere” and Palin’s “CO2 heats the earth”. Each of these viewpoints displays ignorance (or willful distortion) of the physics involved. Renowden’s statement is closest to correct physics but he is specifying the wrong gas and fails to specify the system. “More [water vapour] means more heat retained in the [atmospheric] system” would be correct due to the greater atmospheric volume and heat capacity of water vapour vs CO2 (@ 275 K: Water Vapour 5%, 1.859 kJ/kgK vs CO2 0.036%, 0.819 kJ/kgK) http://www.engineeringtoolbox.com/water-vapor-d_979.html http://www.engineeringtoolbox.com/carbon-dioxide-d_974.html i.e. The GHG role of CO2 is miniscule . Oreskes is clearly out of her depth if she thinks energy is “trapped” in the atmosphere and Palin hasn’t got a clue either if he thinks CO2 “heats” the earth. Although the term “greenhouse” is a misnomer, the effect is easily demonstrated e.g. cold nights in a tropical desert location where the air is dry vs warm nights where the… Read more »

Richard C (NZ)
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Richard C (NZ)

Delete “assures”, insert “ensures”. I’ve just worked an 11 hour shift – not conducive to erudition.

Richard C (NZ)
Guest
Richard C (NZ)

Also should be “e.g. Sahara vs Singapore” – I give up

Huub Bakker
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Huub Bakker

If we are talking heat retained in the atmosphere then you also need to include the latent heat of vapourisation of water as well; the extra heat needed to turn water into water vapour. This adds a one-off figure of about 2400kJ/kg of water evaporated.

If we assume that water vapour increases by 1%, i.e. from 0.05 kg water/kg dry air to 0.0505 kg water/kg dry air, then this adds 0.0005 kg water/kg dry air x 2400 kJ/kg = 1.2 kJ/kg dry air. To get the same amount of heat retained by simply heating up water and air would require a change in temperature of dT = 1.2 kJ/kg dry air / (0.05 kg water/kg dry air x 1.859 kJ/kg water/K + 1 kg dry air/kg dry air x 1.005 kJ/kg dry air/K) = 1.1 C.

So adding a very small amount of water vapour has the same effect as raising the air temperature by more than a full degree.

Richard C (NZ)
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Richard C (NZ)

Huub, A) Would not latent heat of vapourization be from solar energy input (SW radiation) – not GHG re-radiation? B) That energy is not then able to be retained as heat in already full capacity H2O vapour or CO2 at the values given i.e. the energy changes the state from liquid to vapour but it is not then added as Q to the Q of the GHG gases (assuming they are already at full capacity) but to the residual air volume? C) The calculation is for energy requirement – not heat retention (or heat content Q)? http://www.engineeringtoolbox.com/fluids-evaporation-latent-heat-d_147.html CO2 has minimal evaporative effect. on the ocean so atmospheric water vapour from evaporation is not due to atmospheric CO2 effects anyway (contrary to AGW). Dr Roy Clark:- “Over the ocean, the increase in LWIR flux from CO2 is ‘buried in the noise’ of the fluctuations in ocean evaporation from wind and surface temperature variations and changes in downward LWIR flux due to fluctuations in humidity, aerosols and cloud cover” http://venturaphotonics.com/CAClimate.html (see Introduction) I will concede though, that more CO2 means [a little] more heat retained in the [atmospheric] system because although minimal, CO2 does have… Read more »

Huub Bakker
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Huub Bakker

Richard,

I can’t say that I was looking any further than the comment about heat retention. I took this to mean the heat content in the air. If that is the case then the latent heat is important. That was really the only intention of my comment.

If we are talking about air near the Earth’s surface then the latent heat forms part of the heat retention as warm air can pick up water. It doesn’t distinguish between heat that comes from sun, GHGs or anywhere else. If you are talking about air in the upper atmosphere then the latent heat will not form part of the picture because there is no liquid water to evaporate.

Richard C (NZ)
Guest
Richard C (NZ)

This has got me thinking Huub. My original perspective was SPECIFIC heat of STATIC DRY air where heat content is SENSIBLE heat (my interpretation). Sensible and latent heat are thermoDYNAMiC distinctions relevant to transfers and work in my understanding, considerations of which is ENTHALPY (see below) and you are correct to consider the enthalpy of moist air further highlighting the significant role of water in terms of heat (as opposed to the insignificant role of CO2) but I didn’t think it necessary to consider enthalpy merely to compare heat sinks. I don’t think your calculation uses realistic values though (see below). This definition of heat content states:- “a thermodynamic quantity equal to the internal energy of a system plus the product of its volume and pressure; “enthalpy is the amount of energy in a system capable of doing mechanical work”” http://www.thefreedictionary.com/heat+content So you are more correct than I in that respect and my use of Q was also incorrect. I do disagree totally with this however (in terms of latency)- It doesn’t distinguish between heat that comes from sun, GHGs or anywhere else It does, and I think that this is the fundamental… Read more »

Richard C (NZ)
Guest
Richard C (NZ)

Basically, a heat sink comparison between the nominal heat sink values of dry air with the heat sink values of WV.

Addition or reduction of either CO2 or WV in the atmosphere must change the relative proportions of all the other constituents I would have thought.

Huub Bakker
Guest
Huub Bakker

Richard,

Takes a while to read through your entire comment but I can short-circuit part of it by making the point that adding any CO2 to the atmosphere will LOWER the specific heat capacity of the system. That is for the simple reason that, at around 0.79 kJ/kg/K, the specific heat of CO2 is lower than that of air as a whole, about 1.0 kJ/kg/K. Add any CO2 and you will REDUCE the ability of the air to retain heat. Adding water vapour, on the other hand, will increase the specific heat capacity of the air because it has a higher specific heat capacity, at about 1.7 kJ/kg/K.

Does that make your analysis more interesting? 🙂

Richard Treadgold
Guest

You make this sound non-controversial, Huub. But does not this fact, by itself, falsify the proposition that the greenhouse effect might dangerously heat the global environment, much less that it might even run out of control? How could it have been overlooked by professional scientists? They say constantly that increased CO2 heats the atmosphere. Or the oceans, perhaps. Or are they changing the argument, so solar radiation now heats the oceans directly, without recourse to the greenhouse effect?

Do you have a reference to the specific heats? On second thoughts, you would probably just refer me to a science text book, or an encyclopaedia. The kind of thing where you look up details of the Periodic Table or check the speed of light — right? I’ll Google it!

Richard C (NZ)
Guest
Richard C (NZ)

Yes you’ve made it more interesting Huub – I disagree because we need to consider density. Case 1) For increased density of a set volume (mass increase): Increased CO2 and WV will both increase the heat capacity of the set volume, The entire atm volume remains the same and it’s heat capacity is increased. But what would cause density to increase (there’s no constraint)? Case 2a) For same density of a set volume (mass – no change): Increased CO2 will lower the heat capacity of a set volume. The entire atm volume is increased by the gases displaced by the CO2 but the volume displaced has a higher heat capacity than it would be if it had CO2 in it. What then is the nett effect? [I haven’t got the time to do this calc at present] Case 2b) For same density of a set volume (mass – no change): Increased WV will increase the heat capacity of a set volume/ Tthe entire atm volume is increased by the gases displaced by the WV but the volume displaced has a lower heat capacity than it would be if it had WV in it.… Read more »

Richard C (NZ)
Guest
Richard C (NZ)

Huub, I think Gareth Renowden is confusing potential heat capacity with actual measured heat content.in his statement “More CO2 means more heat retained in the system”

It does not necessarily follow that just because there is more CO2 in the atmosphere that more heat will actually be retained; it is conditional on the requisite temperature and pressure conditions . This is proven by the missing hot spot in the critical pressure region about 400 – 200 hPa at 8 – 12 km altitude above the tropics

http://joannenova.com.au/2008/10/the-missing-hotspot/

If the required temperature is not being observed, he’s wrong.

Andy
Guest
Andy

Gareth has some more evidence, in the form of increased heating nights.
This is consistent with greenhouse warming. It is also consistent with increased cloud cover and increased UHI effects. Have these latter been ruled out?

The links to Skeptical Science are worth following. The comments below each post often open up more questions.

Richard C (NZ)
Guest
Richard C (NZ)

Notice that the warm night trend is down since 1999 and the graph stops at 2003, what has happened in the 7 years since then? Typical of Gareth he is still dining out on the 80’s and 90’s warming but he turns a blind eye to the trends of the last decade. The atmospheric carbon vs oxygen graph is interesting. Huub has got me thinking a great deal about the physics of Gareth’s statement:- “More CO2 means more heat retained in the system”. I think that it does not conform to AGW (or physics) and should be something like:- “More CO2 means more WV retained in the atmosphere and therefore more heat retained in the [atmospheric] system IF temperatures rise or are maintained at high levels” AGW is then disproved by either the empirical observation of declining heat content (atmosphere and ocean) AND/OR static or declining WV levels (starting to look that way on both counts). But how do we know what is happening to the long-term composition (the heat sink) of 1 cubic km of atmosphere at altitude 10 km say? My reasoning is:- 1) Start with the composition of the atmosphere… Read more »

Andy
Guest
Andy

I really don’t buy this heating nights argument. Anyone who has spent time in a city at night knows that it retains heat.

We know that there is a lot of UHI contamination in the temperature record.

Has anyone factored this out on the night versus day measurements?

Huub Bakker
Guest
Huub Bakker

I seem to recall a study done recently in the US looking at the temperature trends for weather stations that showed that the night-heating effect is only seen in urban or contaminated weather stations, not rural. I think it was a statement made by Anthony Watts in one of this posts (with link presumably) but I can’t be sure.

Anyway, this would support the idea that the night-heating effect is only due to UHI (including for weather stations that are supposed to be rural but are contaminated by buildings, tar seal etc.)

Andy
Guest
Andy

Huub,
I found one link on C3 Headlines on this nighttime heating topic

http://www.c3headlines.com/2009/11/the-global-warming-boogeyman-it-only-comes-out-at-night-scientists-confirm-1.html

Of course, this doesn’t conclusively “prove” anything, but then science is, or should not be, about “proving” things, but be about creating falsifiable statements

Con Michael
Guest
Con Michael

According to the rigors of scientific discipline,a theory is not worthy of any consideration unless it implies the sort of evidence that would prove it wrong.Predictions based on the theory are checked against the facts.How many anomalous results are sufficient to invalidate a proposition?To paraphrase Einstein…..a mere one.Recent decades are replete with failed global warming predictions.Ergo the AGW theory has been discredited.

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