Out in the Ama-zone

Guest Post by Willis Eschenbach

There have been lots of articles lately discussing the retraction by the UK Sunday Times of their claims about Amazongate. Folks like George Monbiot are claiming that their point of view has been vindicated, that Amazongate is “rubbish” and that skeptics have been “skewered”. So I decided to follow the tortuous trail through the Amazon jungle, to see where the truth lies.

Figure 1. The long, twisted, rainy jungle trail leading to the facts …

First, what did the IPCC say that caused all of the furor? Here’s the quote:

Up to 40% of the Amazonian forests could react drastically to even a slight reduction in precipitation; this means that the tropical vegetation, hydrology and climate system in South America could change very rapidly to another steady state, not necessarily producing gradual changes between the current and the future situation (Rowell and Moore, 2000). It is more probable that forests will be replaced by ecosystems that have more resistance to multiple stresses caused by temperature increase, droughts and fires, such as tropical savannas.  (IPCC, PDF, p. 596)

Scary stuff, climates tipping to a new steady state, 40% of the Amazon rainforest changing to savanna …

Now, this is referenced to Rowell and Moore (PDF). The first problem that arises is that this is a World Wide Fund for Nature (WWF) overview piece, and is as far from peer-reviewed science as one can imagine. The WWF says:

Up to 40% of the Brazilian forest is extremely sensitive to small reductions in the amount of rainfall. In the 1998 dry season, some 270,000 sq. km of forest became vulnerable to fire, due to completely depleted plant-available water stored in the upper five metres of soil. A further 360,000 sq. km of forest had only 250 mm of plant-available soil water left. 46

Note that already we see a difference between the citation (such as it is) and the IPCC statement. The WWF says that the forest is “extremely sensitive” to “small reductions” in rainfall. The IPCC has upped the ante, saying the forest could “react drastically” to “even a slight reduction” in rainfall. In addition, the IPCC has added an uncited claim that the South American “vegetation, hydrology and climate system” could suddenly change to a new “steady state” … be very afraid.

Now, the WWF paragraph has a citation (46). This is:

46 D. C. Nepstad, A. Veríssimo, A. Alencar, C. Nobre, E. Lima, P. Lefebvre, P. Schlesinger, C. Potter, P. Mountinho, E. Mendoza, M. Cochrane, V. Brooks, Large- scale Impoverishment of Amazonian Forests by Logging and Fire, Nature, 1999, Vol 398, 8 April, pp505

The problem is that their citation only supports the second half of the paragraph, the part that relates to the 1998 dry season. It says nothing about the extreme sensitivity of the Amazon. It says nothing about a new “steady state.” Even Dr. Lewis, who convinced the Times to issue the retraction, admits this:

The 40% claim is not actually referenced in the Rowell & Moore 2000 report (they use Nepstad to reference the specific figures in the next sentence). The Nepstad Nature paper is about the interactions of logging damage, fire, and periodic droughts, all extremely important in understanding the vulnerability of Amazon forest to drought, but is not related to the vulnerability of these forests to reductions in rainfall. I don’t see how that can be the source of Rowell’s 40% claim. Its more likely an unreferenced statement by Rowell.

And there, the trail stops. Despite Pachauri’s oft-repeated claim that the IPCC is based 100% on peer reviewed science, the IPCC has referenced a WWF document which:

1. Is not peer reviewed, and

2. Has no further citation for the claim.

So why did the Times have to retract their claim? It was the result of a letter sent to the Times by Dr. Simon Lewis, who claimed that a) he had been misquoted, and b) the IPCC claim was scientifically accurate.

From Dr. Lewis’s statement, I do believe he was misquoted. However, that does not mean that the IPCC statement was correct. Dr. Lewis defends it, saying:

The IPCC statement itself is poorly written, and bizarrely referenced, but basically correct. It is very well known that in Amazonia tropical forests exist when there is more than about 1.5 meters of rain a year, below that the system tends to ‘flip’ to savanna, so reductions in rainfall towards this threshold could lead to rapid shifts in vegetation.

Indeed, some leading models of future climate change impacts show a die-off of more than 40% Amazon forests, due to projected decreases in rainfall. The most extreme die-back model predicted that a new type of drought should begin to impact Amazonia, and in 2005 it happened for the first time: a drought associated with Atlantic, not Pacific sea-surface temperatures. The effect on the forest was massive tree mortality, and the remaining Amazon forests changed from absorbing nearly 2 billion tonnes of CO2 from the atmosphere a year, to being a massive source of over 3 billion tonnes.

The Amazon drought impacts paper was written by myself and colleagues in Science (attached). Here is the press release explaining the sensitivity: http://www.leeds.ac.uk/news/article/36/amazon_carbon_sink_threatened_by_drought

Now, there’s a couple of things to note about this claim. First, other than a paper by Dr. Lewis himself about Amazon carbon sinks, there are no citations. The paper about carbon sinks is interesting, but it does not show anything about a “flip” to savannah, and doesn’t mention the 40% claim.

Second, he does not present any evidence that the 40% statement is correct. Instead, he says that climate models show that the statement is correct … Now, climate model results are interesting, but they are not evidence of anything but the assumptions of the programmers of the models.

And in fact, the 40% claim is called into question by another paper by the same Nepstad cited by the WWF document. It says:

During the severe drought of 2001, PAW10m [plant-available soil water to 10 metres depth] fell to below 25% of PAWmax in 31% of the region’s forests and fell below 50% PAWmax in half of the forests.

Now, if the Amazon were so sensitive, if it “could react drastically” to even a “slight reduction” in rainfall, certainly such a large reduction would make a big difference … but that didn’t happen. There was no “flip” to savannah mentioned in the paper.

Third, Dr. Lewis seems to want us to think that some fraction of the rainforest becoming savannah is supportive of the IPCC claim that:

… the tropical vegetation, hydrology and climate system in South America could change very rapidly to another steady state …

That’s just misdirection. Dr. Lewis does not provide any evidence in support of the alarmist claim that the South American climate is in danger of a rapid change to some other steady state. Which is no surprise to me, since I know of no historical evidence of such a rapid large-scale change in the tropical climate to a much dryer state.

And finally, even Dr. Lewis recognizes that there is no scientific certainty about this question, saying:

This is not to say this there isn’t much uncertaintly as to exactly how vulnerable how much of the Amazon is to moving to a savanna system.

Well … yeah. Given that uncertainly, his claim that the IPCC statement is “basically correct” is unsupportable. “Much uncertainty” means that we cannot make scary statements like the IPCC has done, and we certainly can’t say that they are “basically correct”. All we can say is that they are uncertain.

Before going on to look at some actual data, lets review the story so far:

1. The IPCC made a claim that “Up to 40% of the Amazonian forests could react drastically to even a slight reduction in precipitation”, and that the South American climate could change rapidly to a new steady state.

2. This was referenced to a WWF review paper which was not peer reviewed.

3. The WWF paper had no citation for that claim.

4. Dr. Lewis says the claims are correct. However, like the IPCC, he does not provide a citation for his claim that the 40% statement is correct. He points us to a 2009 paper, of which he is a co-author. It doesn’t contain any support for the 40% claim. He refers to a few climate models, but shows no evidence.

5. Dr. Lewis says that there is “much uncertainty” about the question.

6. Dr. Lewis does not provide any evidence to support the idea that the South American climate is likely to change rapidly to a new steady state.

Now, having reviewed the story so far, lets think about this a bit dispassionately. First, is it theoretically possible for the Amazon to “flip” from rainforest to savannah?

Certainly it can. If the Amazon rainfall went to a tenth of the current value, it would all be savannah. So how much would a “slight reduction” affect the Amazon rainforest?

To investigate this, we can look at the amounts of rainfall around the Amazon. Figure 2 compares the vegetation and the rainfall:

Figure 2. Vegetation map of central South America. The Amazon rainforest is dark green. Violet rectangle show area of measured rainfall shown below in Fig. 3. Red lines show rainfall in millimetres per year.

There are several things we can see from this map. First, rainfall is not the only thing that is limiting the Amazon rainforest. There are areas with less than 1600 mm which are rainforest, and areas with more than 1600 mm which are not rainforest.

Second, at the left edge of the rainforest, we have the Andes mountains. In these areas, the Amazon is limited by elevation rather than by rainfall.

Now, suppose that the rainfall drops by 10%. I’d call that a “slight reduction” in rainfall. Will that affect 40% of the rainforest? No way. If we were to shrink all of the red lines by 10%, we’d only get about a 20% reduction in area … but there are large areas which are not rainfall limited in that sense. So a 10% reduction in rainfall might, and I emphasize might, give us a maximum of a 20% reduction in rainforest area. To get to 40% rainforest loss, we’d need a large reduction in rainfall, not a slight reduction.

But who is claiming that there will be a large reduction in Amazon rainfall? That is a model prediction, and not even one that appears in all of the models. Dr. Lewis says:

Indeed, some leading models of future climate change impacts show a die-off of more than 40% Amazon forests, due to projected decreases in rainfall.

This, of course, also means that some leading models do not show a die-off. Even the models don’t all agree with the IPCC claim.

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.

[UPDATE] Credit where credit is due. I love writing here because I always learn something. The Amazongate story was originally broken by Richard North, whose blog is EUReferendum. Give it a look, lots of good stuff.


newest oldest most voted
Notify of

“Indeed, some leading models of future climate change impacts show”
Yet again, the Incredibly Poor Climatologically Challenged spin machine churns out another smokescreen of alarmism. Your analysis is straightforward, clear and totally refutes their model-based fervor.
I wonder, can we sue the IPCC for mendacity? Or perhaps request a grant to study the effect of the reduction in IPCC spending on model survival rates…..just a wishful thought.


I completely disagree with this irresponsible and unprovable commentary. Next time you could at least attempt to back up your claims with peer reviewed science, Mr. Eschenbach (if that is your real name?).

Keith W.

Nice logic trail, Willis. Simple to follow; if only the MSM would open their eyes so they could see the forest instead of the trees.

John of Kent

Good work, Willis- you should really be in the IPCC!

The rainforest reductions are based junk science. Models with different inputs are used to generate various outputs. Next, the dramatic outputs are deemed likely and those that are not dramatic are deemed as unlikely. Dramatic results are scientific, undramatic ones are unscientific. That’s how the junk science alarmism industry operates. It always based on models.
The citing of a nonpeer reviewed literature remains the scandal here. The 40% number is an exaggeration.
Stefan Rahmstorf immediately seized upon the Times retraction at his blog. http://www.wissenslogs.de/wblogs/blog/klimalounge/medien-check/2010-06-23/sunday-times-zieht-amazongate-zurueck
And then rambled on, citing Jon A. Krosnick bogus study, on how public opinion of climate change was tending to even greater concern.
But I doubt many people are reading his rubbish, as he has gotten only 3 reader comments thus far, i.e. his blog is at about the same level as my hobby, for-fun blog.
Of course, we do not know how many comments he is deleting. I only know my comment was deleted.

Michael Larkin

This is a stonkingly good article, Willis, for which many thanks – it’s the first time I’ve been able to get a good grasp of this story. If people wonder why agnostics like me come to blogs like this, it is because we get articles like this and end up learning stuff from them. One day we hope to become gnostics, whatever the truth might be.

Great post. In an ‘amazing’ conincidence, I happened to examine another aspect of the IPCC statement. Take a look yourself
With regards


Bravo, Willis!


Fantastic posting as always from Mr Eschenbach, posts like this is exactly what’s needed to get the “medias” attention. If only there were a way to get their eyes open and actually read it too…

Capn Jack Walker

Coupla things matter in fear mongering, it always begins up to, in this case up to’s upper limit is 40%, but where is the bottom limit, could be zero per cent.
Weasel words, weasel language.
The amazon is a great Jungle to use, no one actually goes there, it’s not a holiday destination.
Me I don’t know much about it myself, except that it’s mysterious and an icon for fear mongerers.
Up to 40% of women on the planet reckon I am a red hot lover, mind you at 54 with one leg ad arthritis it might be zero per cent too.
Semantics weasel words and they always leave out perspective and real error bands they can have their prognostications held to. better off with me mum when she was going thru meno pause and her seance and tea leave reading stage.
Flim and flam.


Perhaps Dr Lewis will be so concerned, that he will turn up here to defend his defence of (Post) “normal below par climate science”??

Paul Vaughan

While I have no interest in rabidly partisan, untactful spin, I’ll agree whole-heartedly that they appear absolutely clueless about hydrology. I put the blame squarely where it belongs: on corrupt scientists pedaling this nonsense. It is neither sensible nor practical to blame others who have been conned. When it comes to hydrology, they have no option but to admit that it is simply not understood. The understanding of the fundamentals has not yet been developed – and pretending that hydrology is driven by CO2 & GHGs is purely foolish — such fantasy is not only plainly wrong, but an unacceptable hazard to civilization that must be resisted with absolutely rigid resolve. We need to put aside party lines [& goofy partisan spin] to confront these hazardous fantasies. Sensible people must stand up and demand that these issues not be allowed to fall along left/right political lines. That is the true challenge which we face – nevermind climate fantasy. This garbage is playing into the hands of the radical right and tilting our future towards irrational imbalance. Without balance we fall. Too many lefties are unaware that they have been conned on climate fantasies – and unaware that this has eroded their credibility on vitally important social issues. When I run into a righty who is a “denier” I feel the same thing as when I run into a lefty who is a “believer”: anger. Our civilization cannot afford such irrational conflation. It will be sensible people from all political camps who will cooperate to stop this partisan madness (…and then there’s the scientific issue of developing an understanding of climate to tackle)…


Exposing these people is starting to become irrelevant and pointless. If you expose their fraud, then they just invent a new lie that goes along the lines “you are wrong because of xxxx”. Where “xxxx” is just made up.
They lie to coverup their lies. We`ve seen it time and time again with Mann, Jones, Hansen et al.
They know that the MFM (MSM) is part of the AGW fraud, and they know if they lie about your exposure of their lies, then the MFM will print their new-lies as the truth that proves they were right in the first place, and that your exposure was false.
We saw it with the Hockey Stick, Climategate, UHI, etc etc.
It`s pointless treating these people as “scientists” and using argument and facts, because like all hard core criminals – they will continue comitting the crime, until they are caught and face jail sentances.


As usual Willis, excellent work – thank you!

richard telford

“If the Amazon rainfall went to a tenth of the current value, it would all be savannah.”
Unlikely. It would mostly be dry enough to be desert.
“since I know of no historical evidence of such a rapid large-scale change in the tropical climate to a much dryer state.”
Since the historical record for most of the tropics is short, it is useful to look at the palaeoecological record. There are several examples of tropical forest-savanna transitions in the Holocene.
“First, rainfall is not the only thing that is limiting the Amazon rainforest.”
Annual precipitation is certainly not the only factor. The seasonal distribution of rain is as important, especially the length and severity of the dry season. In some areas edaphic factors are important.

Willis, thank you for this. Succinct and clear as ever.
The pro-AGW view is finding that when you point a finger at someone, you have three pointing back at yourself, and having pointed at skeptics and cried “but it is not peer-reviewed” they have to judge by their own metric.
You know, just thinking how much the whole peer-review thing stinks, we could have a ‘generation’ of scientific literature that is skewed by climate change. Not just what gets published and what doesn’t, but what the published papers say and how they say it…. and how it is cited and reported.
Environmentalists divide into two groups – those who fear for the Earth and think that any change they attribute to humans is or will be detrimental, and those who see it as adaptable and repairable. You can sense the frustrations of the likes of Dr Lewis (who I assume is in the former camp) who have formed a set of beliefs, based on their experience and projection of their fears, but now have to back up their opinions with references which…. aren’t there!

allen mcmahon

The idea that 40% of the Amazon forests are at risk from a small reduction in rainfall is absurd. The most alarming scenario is represented by the Amazon “dieback” theory proposed by Cox et al 2004 It is based on the HAD3 GCM , a model that predicts the greatest reduction in rainfall for the Amazon in 21st century, and they use the one senario that predicts the least rainfall despite the fact that this GCM underestimated 20th century rainfall by 20%. A paper by Malhi et. al.2009 PNAS found that in the unlikely event that Cox proved correct at the most 600,000sq.kms. of forest, could revert to savanna and that the core Amazon rainforests were not at risk. As the Amazon forests cover some 8,200,000 sq kms this is less than 8% of the total. Only 2 of 19 models present senarios that could result in conditions leading to widespread savanna. If we only chose the 3 models that accurately approximated 20th century rainfall the prognosis is for no change in the 21st century and most models predict increased rainfall for the 21st century. In terms of senarios at one extreme the Hadley GCM postulates a 21% reduction in rainfall for the 21st century and an increase in the dry season of up to three months while at the other extreme the GISS ER model opts for a 10% increase in rainfall and a reduction of the dry season of one month. 20th century climate in the Amazon exhibited stability with no uni-directional trends and research by Marengo identified cycles that correspond with ENSO and PDO cycles. Despite compelling evidence to the contrary it came as no surprise that Dr Pachauri in a recent Yale 360 opinion piece opted for the “die back” theory proving beyond doubt that politics rather than science drives the IPCC.

James Evans

Thanks, that’s all very clear.
You have rained on the alarmist parade.

Baa Humbug

Don’t you love it when they switch from one measurement to another? Like the following…

Up to 40% of the Brazilian forest is extremely sensitive to small reductions in the amount of rainfall. In the 1998 dry season, some 270,000 sq. km of forest became vulnerable to fire, due to completely depleted plant-available water stored in the upper five metres of soil. A further 360,000 sq. km of forest had only 250 mm of plant-available soil water left.

Scary stuff that 270,000 sq.km and 360,000 sq.km That must be close to the 40% they’re talking about right?
The amazon basin alone is 6,151,000 sq.km the higher end 360,000 sq.km would be 5.9%
Also, the paper says this area became vulnerable to fire. It doesn’t state whether it actually burnt and how much of it burnt.
I’d bet much much less than 360,000 smelled smoke,

Rhys Jaggar

Presumably 100% of the Amazon is susceptible to rapid growth under conditions of rain also??
So what I see is this: most of the time, the Amazon forest is growing rapidly, occasionally there is a drought and a fire.
This is nature at its most natural and whether humans are there or not, it happens.
What is unnatural is to highlight the effects of drought without highlighting the effects of rain. Not to mention the frequency of the two scenarios…………
I suspect you will find that parts of the Sahara desert were once forests. They aren’t now. And the reason they aren’t? Natural climate change. Nothing to do with humans……
Now I grant you that chopping down trees in the Amazon will reduce the size of the forest…………..and that the more you reduce transpiration rates by plant life, the less likely you are to enjoy daily thunderstorms………..although with a monstrous outflow like the Amazon, you’ll need to cut a huge amount of the forest down before you don’t get any storms downstream……….


This argument is based solely on logic and so falls short on the internationally accepted and validated consensus scale that governs modern climate science.
If you seek to drastically change the world order it is hard to find a more suitable motivator than a looming catastrophe of cataclysmic proportions. This is a well known and finely perfected human art that has been perfected during our short history on earth. If you are a bit to aggressive in projecting the immediacy of the upcoming catastrophe in order to further appeal to the majority of shortsighted world citizens you might run into troubles like the one presented above. In that case you naturally have to adapt. Great adaptation techniques include “I was misquoted” etc.
I speculate that we will have the entertaining experience of seeing the AGW proponents developing this art during the coming years.

I collected model cars in my early adulthood. I was an utter petrolhead then (stll am, after half a century of avidly following F1 and other series of events such as the IOM Motorcycle TT) but I never saw any link between a make of car or motorcycle and models of them.
While scientists may invest huge faith in modelled behaviour of climate, more rational among us know the difference between a model and reality. Some scientists must have difficulties with their id when passing an Anne Summers shop window!


Perhaps you could write to the Times and ask them to retract the retraction..?


Dr Simon Lewis est directly funded by wwf-Tanzania and wwf-US :


The CAGW community had the opportunity to deal with the problems of the IPCC and other promotional problems and has instead decided in many cases to bluff their way out by pretending there are no problems and to blame those who pointed out the problems.
Sort of like the Catholic church in dealing with Luther and Galileo.

allen mcmahon

Their was an error in my earlier post, the Cox die back theory is not the most absurd of the Amazon theories the dubious honor goes to none other that Dan Nepstad. In a paper he produced for the WWF in 2007 with the conservative title “Amazon’s Vicious Cycles” Nepstad claims that 55% of the Brazilian forests could be destroyed within 20 years, note the nice qualifier “could”. This document was the basis of the REDD submission presented at the Bali conference in December 2007 by the Woods Hole Research Center, authored by none other than rather busy Dan Nepstad , who seems to be alternately employed by the WHRC, WWF and the Moore Foundation( a major contributor to the WWF). The REDD scheme’s intention is to preserve the worlds forests by using a market based emissions trading scheme. The WHRC , is aided by Goldman Sachs, a foundation sponsor of the WHRC. It is great when an independent scientific organization, despite the numerous environmental activists on their board, and a philanthropic financial institution combine their resources for the benefit of the world.

Phil Clarke

… And there, the trail stops […] other than a paper by Dr. Lewis himself about Amazon carbon sinks, there are no citations […]
Really? Lewis refers us to his colleague Daniel Nepstads article on the issue both online and as an Appendix to his PCC Complaint. This is amply referenced, here’s the relevant extract:
” Our 1999 article (Nepstad et al. 1999) estimated that 630,000 km2 of forests were severely drought stressed in 1998, as Rowell and Moore correctly state, but this forest area is only 15% of the total area of forest in the Brazilian Amazon. In another article published in Nature, in 1994, we used less conservative assumptions to estimate that approximately half of the forests of the Amazon depleted large portions of their available soil moisture during seasonal or episodic drought (Nepstad et al. 1994). After the Rowell and Moore report was released in 2000, and prior to the publication of the IPCC AR4, new evidence of the full extent of severe drought in the Amazon was available. In 2004, we estimated that half of the forest area of the Amazon Basin had either fallen below, or was very close to, the critical level of soil moisture below which trees begin to die in 1998. This estimate incorporated new rainfall data and results from an experimental reduction of rainfall in an Amazon forest that we had conducted with funding from the US National Science Foundation (Nepstad et al. 2004). Field evidence of the soil moisture critical threshold is presented in Nepstad et al. 2007. ”
Which leads Nepstad to state:
In sum, the IPCC statement on the Amazon was correct. The report that is cited in support of the IPCC statement (Rowell and Moore 2000) omitted some citations in support of the 40% value statement.
Hope this helps.

Mike McMillan

If there is any conversion to savanna, it is likely to come from local logging and burn-clearing for agriculture. Because the heavy rain leaches nutrients from the soil, most Amazon nutrients are held in the biomass. Since logging removes that biomass immediately and slash and burn ag removes it over a longer time, you don’t get the regrowth, but that isn’t a rainfall problem.
With reduction in rainfall, you’d first go through all the forest stages that populate non-rainforest tropical areas before you got to open savanna, and that might take centuries. Soil nutrients will continue to wash down slowly from the Andes.
Reduced rainfall would be beneficial to agriculture in that respect, leaving imported potash and locally produced nitrates available in the soil longer. Gotta look on the bright side.


I have to say, I am becoming increasingly un-willing to even discuss MODELS as actual climate. I wish articles would state at the beginning that the predictions in them are based on models. Then it would be clear that we are discussing models and not actual events.
I’m sure models can be useful tools, but until they can actually predict the past or the future I’m afraid they are just academic.
Any honest climate scientist’s interview would conclude with “but we just don’t know yet”.

tim c

I’m beginning to feel that the people creating “models” are using Edsels as benchmarks. It’s time for the modeling police to require “real world possibilities” and not be filled with worst case scenarios and adjustments for “public attitude adjustment”(propaganda). The models look like they are all “rube goldberg” scenarios of run away reactions.

That’s amazing – even their own models contradict the claim…..
Any idea exactly how much rainfall reduction would be needed to cause a 40% die-off? I’m guessing quite a bit.

Is there any IPCCish claim, which can withstand exposure to real data?
Temperature: http://climexp.knmi.nl/data/icrutem3_285-310E_2.5–12.5N_na.png
Precipitation: http://climexp.knmi.nl/data/iprca_285-310E_2.5–12.5N_na.png
One gotta love the KNMI Climate explorer.
Note, that IPCC claim contains twice “could” and once “probable”.

Peter Miller

As any good alarmist would say: “Don’t confuse me with the facts, my mind is made up.”


“The great tragedy of science is the slaying of a beautiful hypothesis by an ugly fact.” – Thomas Henry Huxley (1825-95)


As I sat here reading this article an advert for the WWF was broadcast on the television. They were asking for money to save the Jaguar because “20% of the Amazon rainforest has already disappeared”. This time they blamed logging etc (not climate) for the present decrease and future decreases. Obviously they don’t have enough confidence in the IPCC version to claim another 40% will disappear due to climate change unless you give them money.
It’s in the WWF own financial interest to promote alarmist forecasts. The more alarmist the claims, the more money they can fool the public into giving. But any claim they make has to get past the Advertising Standards Authority and I doubt this one would.

anna v

Thanks Willis.
You are a great investigator for us.

Peter Plail

Thank you for taking us by the hand and leading us through the arguments step by step. All very logical and reasonable.
I now wait a step by step refutation of all your points by Dr Lewis or one of his cohort, with the same clarity.
And wait…….
And wait….

Fredrick Lightfoot

As usual Willis puts in the missing link, logic, well done Willis, and all this work without a grant? but then grants don’t pay for logical results.

Harry Lu

positive feedback
clearance fire smoke -low rainfall – fires/smoke -low rainfall
[http://] irina.eas.gatech.edu/EAS_spring2008/Andreae2004.pdf
Greenhouse on ENSO
[http://] iprc.soest.hawaii.edu/users/axel/GL11677W01.pdf
Drought and Fire in the Greenhouse
Ecological and Climatic Tipping Points of the World’s Largest
Tropical Rainforest, and Practical Preventive Measures
WWF! but An independent scientific review of the content of this report was conducted by Prof. Yadvinder Malhi, Professor of Ecosystem Science at Oxford University.
[http://] [www] .whrc.org/policy/pdf/cop13/Amazon-Vicious-Cycles.pdf#search=”Nepstad et al amazon”
Tipping point.
This is a very silly statement , made without backup “Now, if the Amazon were so sensitive, if it “could react drastically” to even a “slight reduction” in rainfall, certainly such a large reduction would make a big difference … but that didn’t happen. There was no “flip” to savannah mentioned in the paper”
It is obvios to even me that the tipping point of ecology is not a rainforest-to-no-forest-in-a-year-situation. Ecological tipping points take time to be evident but once the tipping point is passed it may be difficult to turn back. All trees do not die in a year. They may, for example, become less resistant to pest attack and then die over a number of years etc.


Good analysis, Willis. You have destroyed the IPCC claim in two ways. Firstly, by following the paper trail which leads to a dead end of oft vague and unsupported assertions, and secondly, by taking a practical, common sense appraisal of the actual rainfall data, to show that a small reduction cannot possibly lead to a changeover to savannah.
To my mind however, the saddest thing about this episode with “The Times” is that they appear totally unable to defend themselves from the ludicrous charges of Lewis. Have they no scientific journalists who can defend their position, as you have done? It is as if a national newspaper, on uncovering a major political scandal, suddenly published a retraction because some minister wrote a letter saying that the scandal had not in fact occured.

Chris in OZ

Amazongate Mk II
How to hide the decline of IPCC credibility !!


Nicely dealt with.
Now what if the Amazon WAS savannah? Professor Philip Stott wrote this a few years ago: Tropical Rain Forests – Exposing the Myths http://www.probiotech.fsnet.co.uk/trf.html
“At the end of the Last Ice Age, only some 12,000 to 18,000 years ago, the tropics which are today occupied by these so-called ‘ancient cathedrals’ were seasonal savanna grasslands, both cooler and much drier than now.”
It is based on an earlier paper called Jungles of the Mind, http://www2.csusm.edu/spanish/undergradcenter/jungles_of_the_mind.htm
Interesting stuff.

The definitive account of Amazongate

Charlie Barnes

Nice one, Willis.
It’s curious how people with an apparent political point to make don’t seem to think that evidence matters.


WFF pfft. WWF has become the largest get rich quick scheme factory in the world.
If they can’t, or don’t, set up a daughter organization, or company, to charge other organizations and companies if they don’t like it.
Fish farmers bad — unless they pay. Loggers bad — unless they pay. Oil companies bad — unless they pay. Heavy industry bad — unless they pay. Et Cetera. Unless you pay for WWF certificate of approval or what ever everyone is bad. Other “climate organization” are of course approved, somewhat, to tax everyone as well if it’s a “good” scheme.


Small point, Willis: it was the Sunday Times which retracted, not the (daily) Times. Different newspapers, different editors, different staff – though same proprietor (R Murdoch).

Jack Simmons

Baa Humbug says:
June 27, 2010 at 3:08 am

Don’t you love it when they switch from one measurement to another? Like the following…
Up to 40% of the Brazilian forest is extremely sensitive to small reductions in the amount of rainfall. In the 1998 dry season, some 270,000 sq. km of forest became vulnerable to fire, due to completely depleted plant-available water stored in the upper five metres of soil. A further 360,000 sq. km of forest had only 250 mm of plant-available soil water left.
Scary stuff that 270,000 sq.km and 360,000 sq.km That must be close to the 40% they’re talking about right?
The amazon basin alone is 6,151,000 sq.km the higher end 360,000 sq.km would be 5.9%
Also, the paper says this area became vulnerable to fire. It doesn’t state whether it actually burnt and how much of it burnt.

Baa Humbug,
Here are some other things I find strange. It is claimed 40% of the Amazon is “extremely sensitive” to small reductions in rainfall.
1998 saw, not a small reduction in rainfall, but a DROUGHT.
That was 12 years ago.
Certainly, if 40% of the Amazon is “extremely sensitive” to a “small reduction in rainfall”, wouldn’t any of the Amazon react to a DROUGHT?
I would expect if all the above were true, this drought affected region would be well on its way to savannah hood. Yet, nothing is mentioned in follow up reports.
I did catch some episodes of River Monster. It seems there’s still enough water in the Amazon to grow some mighty big and fearsome fish.

Now there’s a guy with a good job. He gets to go fishing and paid for it to boot.
Almost as good as a programmer for a GCM. Paid to program and you don’t need to produce anything verifiable.

allen mcmahon

Mike MCMillan @ 3.34am
The dangers from logging have diminished in recent years. Since its peak in 2004 logging has reduced been by 64% due to a government crackdown on illegal logging, the establishment of protection zones that cover more than 30% of Brazil’s forests and act as a buffer zone between cleared land and the core rain forests, limiting the clearance of privately owned land to 20% and the growing lack of land suitable to pasture or agriculture. What the alarmists never mention is that pasture land soon degrades and that 32% of cleared land has been revegitated either by plantation timber or natural regrowth. They also fail to mention that the FAO consistently over estimated logging until recent years when satellite coverage provided a more accurate means of assessment.

Amazon = $
Lots of attractive graphs, including a hockey stick, from Nepstad.

Mr Eschenbach, if you had actually followed the debate instead of trying to reinvent the wheel, you would be aware that the WWF has asserted that the problem stems from a reference accidentally omitted from its report, as in the claim that “WWF acknowledges that a reference to Fire in the Amazon as the source of the 40% claim outlined above was mistakenly omitted during the editing process of the Global Review of Forest Fires report.” It goes on to say:
WWF’s source for this statement is Fire in the Amazon, a 1999 overview of Amazon fire issues from the respected Instituto de Pesquisa Ambiental da Amazônia (IPAM – Amazon Environmental Research Institute). The source quotation from Fire in the Amazon reads “Probably 30 to 40% of the forests of the Brazilian Amazon are sensitive to small reductions in the amount of rainfall.”
Intriguingly, the WWF then goes on to say that: “Our report does NOT say that 40% of the Amazon forest is at risk from climate change.”
The argument has thus already progressed to a discussion over the provenance of “Fire in the Amazon”. It turns out that this is edited (in fact, largely written) by Daniel Nepstad, and is not peer-reviewed. Thus, we have the IPCC citing an assertion in a WWF document which is “accidentally” unreferenced but, when the reference is identified, it relates to a non-peer-reviewed publication.
It then gets better, for “Fire in the Amazon” refers to the Brazilian rainforest (less then half the total) while the IPCC asserts that the 40 percent mentioned applies to the Amazon basin as a whole. Thus, even if “Fire in the Amazon” could be relied upon as a legitimate source (which it cannot), it still does not support the IPCC assertion.
All this and much more can be read about on EU Referendum, including this comprehensive analysis which pre-dates yours by three months and which, had you noted it, would have significantly improved your exposition.
I suppose this is a long-winded way of saying that you are not the only toiler in the vinyard. Some of us have been at this specific theme a lot longer than you and a little bit of acknowledgement would not only not go amiss, but might actually benefit WUWT readers.