Is there ANY Greenhouse effect at all?
The idea that CO2 has a "greenhouse" (temperature-raising) effect on the earth is increasingly being mocked as violating basic laws of physics. The latest mocker is Claes Johnson, a mathematics professor at the Kungliga Tekniska högskolan in Sweden. (Kungliga Tekniska högskolan translates as Royal Institute of Technology. KTH is one of Sweden's most distinguished universities). See below
AGW Myth of Back Radiation
AGW alarmism is based on an idea of "back radiation" or "re-radiation" from an atmosphere with greenhouse gases, but the physics of this phenomenon remains unclear.
To test if "back radiation" is a real phenomenon, we suggest the following experiment: On a night with moon-light so feeble that you can cannot read a newspaper, place yourself in front of a mirror letting the moonlight reflect from the newspaper to the mirror and back again, and check if you can now read. You will probably find that the paper is still unreadable, as if "back radiation" does not give more light.
To give this experiment theoretical support we consider the mathematics of wave propagation from a source at x=0 (Earth surface) to a receiver at x=1 (atmospheric layer) described by the wave equation (as a model of Maxwell's equations describing light as electromagnetic waves):
U_tt - U_xx = 0 for x in the interval (0,1)
with solution U(x,t) being a combination of waves traveling with velocity +1 and -1 along the x-axis, and with subindices indicating differentiation with respect to space x and time t. The boundary condition at the receiver may take the form
AU_t(1,t) + U_x(1,t) =0
with a positive coefficient A signifying:
* A = 0: soft reflection with U_x(1,t) = 0
* A large : hard reflection with U_t(1,t) = 0
* A = 1: no reflection: transparent absorption of all incoming waves at x = 1.
The basic energy balance is obtained by multiplying the wave equation by U_t and integrating
with respect to x to give:
E_t + AU_t(1,t)^2 = -U_x(0,t)U_t(0,t) = Input Energy.
where E(t) is the energy of the wave over the interval (0,1). Assuming that E(t) stays constant so that energy is no accumulating in the interval (0,1), we have that
Output Energy = A U_t(1,t)^2 = Input Energy.
In particular, with soft reflection with A = 0, the Input Energy is also zero. We learn that it is not possible to "pump the system" by reflection at x = 1: If you change from transparency with A = 1 to reflection with A = 0, the system reacts by refusing to accept Input Energy.
Ergo: Reflection/back radiation cannot increase the insolation to the Earth surface.
(Back radiation seeks support in a description of light as a stream of particles proposed by Newton, which was replaced by Maxwell's wave theory in the late 19th century).
What Does The U.S. National Climate Data Center (NCDC) Say About Global Temperatures & "Tipping" Points?
With all the recent talk about the warmest month, the warmest first 5-months of a calendar year, or the warmest calendar year-to-be (maybe), it's probably a good time to review past NCDC global temperature data in a context that goes beyond the extremely short-term periods of 1 month, 5 months or even a calendar year. As a reminder, it's fair to point out that alarmist-profiteers, such as politicians, global warming scientists, celebrities and reporters, want everyone to focus on short-term movements and the fear of "tipping points," and ignore the more critical, longer-term historical context. (click on any image to enlarge)
Graphs 1A and 1B reveal that global temperatures have been experiencing a modest flat to cooling trend over recent years. Note that chart 1B actually includes the huge spike in temperatures due to nature's super El Niño - even with that impressive spike, global temperatures barely increased at a +0.60°C increase per century. Think about it - that's 13 years of essentially very tepid warming (darn close to being flat) despite all the wild, hotter-than-hell predictions of the likes of John Kerry, Obama, Al Gore and James Hansen.
Charts 2A and 2B represent longer-term periods of distinct non-warming and warming periods, per the NCDC data. The great "global-warming" scare is primarily based on the 25 year period ending in 2001 (graph 2B). The temperature increase of a +1.60°C per century trend for that recent period is not even close to being "unprecedented" warming, and is barely different than the warming that is shown in graph 3B. A +1.60°C per century trend is a temperature blip that will absolutely not cause any of the popular catastrophic claims as eagerly publicized by the vast majority of Democrats/leftists/liberals/progressives.
Above graphs 3A and 3B show the NCDC instrumental temperature record dating back to the late 19th and early 20th century. Beginning in 1880, there was an extended cooling period. Graph 3B represents the 33 year warming duration that got its start around 1912. In terms of length and overall warming, the 1912-1944 warming is almost identical to the "Great Warming" of 1977-2001. Taking the above temperature data and putting it in a longer NCDC temperature record view, the below graph provides the needed context.
When all the warming and cooling periods are combined, there has been overall warming of +0.6°C since 1880, which is entirely normal, considering the realism that world temperatures have been on a natural warming trend since the incredible coldness of the Little Ice Age. Even with the large increase of CO2 levels since 1880, the overall warming is nothing extraordinary or dangerous. And just to be clear, the natural cycles of warming and cooling will keep global temperatures from jumping to the ludicrous heights (as the red dots represent on the above chart) that warming alarmist scientists and eco-activists speculate about.
One last graph and note:
Did the "Great Warming" of 1977 to 2001 actually occur? All the previous charts are based on the NCDC "adjusted" global temperatures not the raw, original thermometer readings.
As the above chart reveals, the NCDC scientists have made every conceivable effort to adjust more recent temperatures to be warmer, and to make pre-1945 warming cooler. Although it's clear that global warming has taken place, there is a very high likelihood that a significant portion of recent global warming is of a human fabrication. Finally, have real-world temperatures reached a "tipping point"? The real-world facts don't support that hysterical speculation in the least - it's only in a eco-sexual fantasy dream of an Al Gore, and his ilk, where that climax occurs.
Amazongate: the missing evidence (Still missing)
The story of the IPCC’s claims about threats to the Amazon rainforest takes another bizarre turn
Last week the beleaguered global warming lobby was exulting over what it took to be the best news it has had in a long time. A serious allegation, which last January rocked the authority of the UN’s Intergovernmental Panel on Climate Change, was “corrected” as untrue by The Sunday Times, the newspaper which most prominently reported it. The reputation of the IPCC, it seemed, had been triumphantly vindicated. The growing tide of scepticism over climate change had at last been reversed. But this episode leaves many questions unanswered.
The “correction”, gleefully quoted by everyone from the WWF and The New York Times to The Guardian’s George Monbiot related to what was known as “Amazongate”. This was one of the series of controversies which exploded round the IPCC last winter, when it was shown that many of the high-profile claims made in its 2007 report had been based on material produced by environmental activists and campaigning groups rather than on proper, peer-reviewed scientific evidence.
One example, also reported in The Sunday Telegraph, was the IPCC’s much-publicised claim that climate change, leading to a reduction in rainfall, was threatening the survival of “up to 40 per cent” of the Amazon rainforest. The only source the IPCC could cite for this in its report was a document from the environmental advocacy group WWF. But last week The Sunday Times, in its prominent “correction” to its own story, conceded that the IPCC’s claim was “supported by peer-reviewed scientific evidence” after all. Not identified, however, was the nature of this peer-reviewed evidence. Where is it?
The story of “Amazon-gate” has unfolded through three stages. Step one was the passage in the IPCC report almost identical to one made in a non-peer-reviewed WWF paper of 2000 on forest fires in the Amazon. Specifically the IPCC stated that “up to 40 per cent of the Amazonian forests could react drastically to only a slight reduction in precipitation”. But the only source the WWF in turn had been able to cite to support this was a paper published in Nature in 1999, from a team led by Dr Daniel Nepstad, formerly employed by the WWF but now the “senior scientist” with another advocacy group closely linked to the WWF, the Woods Hole Research Center. Certainly Nepstad’s paper was peer-reviewed: however its subject was not climate change but the impact on the Amazon rainforest of “logging and fire”. It found that “logging companies in Amazonia kill or damage 10-40 per cent of the living biomass of forests”. This had nothing whatever to do with global warming but was cited as the origin of that “up to 40 per cent” figure later used by the WWF and the IPCC.
Step two, when all this was reported last January, was a disclaimer from the WWF, emphasising that its 2000 report did “not say that 40 per cent of the Amazon forest is at risk from climate change”. But it went on to say that the real source for its 2000 paper (which had been “mistakenly omitted”) was another paper, “Fire in the Amazon”. This was also written by Dr Nepstad, as head of yet another advocacy group linked to Woods Hole, the Amazon Environmental Research Institute. Although it was now being suggested that this paper should have been cited as the original source for the IPCC’s claim, it too was not peer-reviewed. Thus, twice over, the IPCC’s claim appears to rest both on non-peer-reviewed science and on studies not related to global warming at all.
So great was the IPCC’s embarrassment over these revelations that the story moved to a third stage. Various scientists, led by Dr Nepstad, suggested further studies which might justify the claim. But an exhaustive trawl through all the scientific literature on this subject by my colleague Dr Richard North (who was responsible for uncovering “Amazongate” in the first place), has been unable to find a single study which confirms the specific claim made by the IPCC’s 2007 report. If one exists we would very much like to see it.
There are several studies based on computer models which attempt to estimate the possible impact of climate change on the Amazon rainforest, but none of these have so far supported that 40 per cent figure. Other researchers in turn have been highly critical of these models, suggesting that they are too crude to replicate the complex workings of the Amazonian climate system and that all observed evidence indicates that the forest is much more resilient to climate fluctuations than the alarmists would have us believe.
Nothing did more to excite attention over the effect of climate change on the rainforest than the exceptional drought of 2005, just when the IPCC’s 2007 report was being compiled. Since then, however, abnormally heavy rainfall in the region has brought disastrous floods to Brazil, both last year and again last week.
In other words there is a real mystery here. Nothing so far made public seems to justify an assertion that the IPCC’s specific claim is “supported by peer-reviewed scientific evidence”. In view of all the controversy this issue has aroused over several months, it might seem odd that, if such evidence exists, it hasn’t been produced before. Is it not now a matter of considerable public interest that we should be told what it is?
AS A PERSONAL footnote to this sorry tale, no one crowed more hysterically over this story last week (or got it more wrong) than The Guardian’s George Monbiot. Inter alia, he accused me and Dr North of having been “responsible for more misinformation than any other living journalists. You could write a book on all the stories they have concocted, almost all of which fall apart on the briefest examination.”
I would remind him that, on the only occasion he tried to do this, boasting that it had taken him just “26 seconds” to catch me out, he was soon forced to apologise to his readers that he had got his point hopelessly wrong, and that I was right. Silly old Moonbat should learn when it is wiser to hold his peace.
The FACTS about the Amazon rainforest
Excerpt from Willis Eschenbach
However, all of this, all of the claims and counterclaims, and the models, and Dr. Lewis’s letter, and the cited scientific documents, all run aground on one ugly fact:
The data shows no change in Amazon rainfall in a century of measurements
Figure 3 shows three different ground-based observational datasets, along with the recent Tropical Rainfall Measuring Mission (TRMM) satellite data.
Figure 3. Four Amazon rainfall datasets, covering the rectangular area shown in violet in Fig. 2 (2.5°N–12.5°S, 72.5°W–50°W). Note the generally good agreement between the four datasets (including the TRMM satellite data)
The main feature of this dataset is its stability. Note the lack of any trend over the last century, and the lack of any large excursions in the rainfall. It stays between two and two and a half metres per year. There are no really wet years, and no really dry years. 95% of the years are within ± 10% of the average rainfall. There are individual dry years, but no prolonged periods of drought.
So while Dr. Lewis says (correctly) that rainforest can change to savannah, he is not correct that 40% of the Amazon is at risk from a “slight reduction” in rainfall. More to the point, there is no evidence to indicate that we are headed for a reduction in Amazon rainfall, “slight” or otherwise. That is a fantasy based on climate models.
The reality is that despite the globe warming by half a degree or so over the last century, there has been no change in the Amazon rainfall. As usual, the IPCC is taking the most alarmist position possible … and Dr. Lewis is doing all he can to claim that the IPCC alarmism is actually good science.
Unfortunately for both the IPCC and Dr. Lewis, here at the end of a long, twisted, and rainy jungle trail, we find that the facts inconveniently disagree with their claims.
The modellers have learnt nothing
They are still doing what was recognized as bogus at least 30 years ago
If you gave me the following paper after replacing the author’s examples of econometric and energy models with climate models, I could not have told it had been written in 1981.
Ascher, W. (1981). The forecasting potential of complex models. Policy Sciences, 13(3), 247-267. doi:10.1007/BF00138485
Here are some extracts.
On the contrast between bad performance record and large volume of research:
Unless forecasters are completely ignorant of the performance record, or are attracted solely by the promotional advantages of the scientific aura of modeling, they can only be attracted to its potential benefits not yet realized.
On the difficulty of retrospective evaluation of model performance when there are competing scenarios:
When no scenario is designated as most likely, the scenarios must be regarded as exogenous factors, whose likelihoods are not at issue in the modeling exercise. The model produces a set of projections, each posited as correct if the corresponding condition or scenario were to hold, but without implying that any particular one will hold or that some are more likely than others. In this case, the retrospective evaluation of forecast accuracy must proceed by first establishing which condition actually prevailed, and then measure the discrepancy between the projection tied to that condition and the actual level of the predicted trend. If it is still too early to evaluate a set of conditional forecasts retrospectively, the spread of conditional forecasts of the same trend for the same year can be used as one indication of uncertainty or minimum error, but only if the conditional is the same for every forecast of the set.
On using model consensus to judge model validity:
[E]ven the agreement across models need not be an indication of validity; they could all be wrong. For example, all energy models predicting the 1975 levels of U.S. electricity, petroleum, and total energy consumption projected these levels higher than they actually turned out to be. This confident consensus was no guarantee that the models were correct then; any consensus among models’ predictions in the future may be equally misleading.
… [S]imilar models undergoing similar judgmental censorship by modelers holding similar outlooks on the future can so easily reassure all parties that the future is seen with certainty.
On using the fact that models are physically based as an argument for model correctness:
Complex models are formulated by specifying assumptions and hypothesized relationships as explicit, usually mathematical propositions. While this procedure is often very helpful in uncovering inconsistency and vagueness in the initial ideas or verbal formulations, it cannot establish the correctness of the model’s propositions. Models express assumptions, but do not validate them. If the modeler tries to ensure the validity of the model’s propositions by focusing on disaggregated behavior of presumably greater regularity, the problem of reaggregating these behaviors to model overall patterns becomes another potential source of error. If the modeler only includes relationships proven by past experience, there is no guarantee they will hold in the future. There is no procedure or format of model specification that guarantees the validity of this specification.
On the effort required:
Since rigorous, elaborate analysis [of models and their outputs]is time consuming and expensive, there has been a natural tendency for forecasters to pour their efforts into grand, once-and-for-all projects, carried out only infrequently and yet used long after they are produced because the immense effort makes them seem definitive.
On the likelihood of modelers to reconsider:
[A]fter the modeler has spent years developing optimization routines, apparent violations of … assumptions are more likely to be accommodated by patchwork modifications, or disregarded altogether as short-term aberrations, than they are to trigger the abandonment of the model altogether.
… [M]odel revision, which seems to the cynic to be an ad hoc effort to keep a fundamentally misspecified model more-or-less in line with reality, is often regarded by the model builder as the normal routine of science.
New Australian PM won't act on climate without consensus
Which she knows she won't get. Clever: Makes her sound good to the ratbags but costs nothing
Labor failed to convince the public a carbon tax was necessary, Prime Minister Julia Gillard says. Ms Gillard said she was concerned about the government's proposed emissions trading scheme because community consensus had not been achieved.
Asked if she was behind the delay of the ETS because it was hurting Labor, Ms Gillard said she had concerns. "I was concerned that if you were going to do something as big to your economy as put a price on carbon, with the economic transfer that implies... you need a lasting and deep community consensus to do it," Ms Gillard told the Nine Network. "I don't believe we had that last and deep community consensus."
The prime minister said she believed Australia should have a price on carbon. "I will be prepared to argue for a price on carbon... so that we get that lasting and deep community consensus," she said. "But we are not there yet."
Ms Gillard said the government could take practical measures. "I believe in climate change. I believe it's caused by human activity and I believe we have an obligation to act," she said. "And I will be making some statements about some further things we can do to address the challenge of climate change as we work to that lasting and deep community consensus."
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