New Ecology Paper Challenges "Tipping Point" Meme
The state of humanity is getting better every day. On the whole, people are richer, healthier, and living longer than ever before. We are also a less violent species, it seems. Statistically speaking, my two boys, born in 2004 and 2007, can look forward to a nice long life. Several years ago, a Duke University demographer said:
It is possible, if we continue to make progress in reducing mortality, that most children born since the year 2000 will live to see their 100th birthday — in the 22nd century.
There’s just one problem. The planet they live on is going to be hotter, stormier, and possibly an ecological wasteland. At least that’s what scientists have lately been projecting. The state of the environment, they say, is lousy: Earth is nearing or on the verge of a dangerous tipping point. (See what you have done, Malcolm Gladwell?) As some have noted, there is an unfortunate disparity between the outlook for humanity and the outlook for the planet.
But what if we’re getting a little ahead of ourselves here? What if this tipping points meme is a bit overwrought and not as imminent as we have been led to believe? That is essentially the argument five earth scientists have put forth in a study published this week in the journal Trends in Ecology and Evolution.
Yes, the authors admit there are big red flags we need to pay attention to–the continuing loss of biodiversity, global warming, deforestation, etc–but they argue:
Even where tipping points have occurred on local and regional scales, there is empirical and experimental evidence to suggest that many ecosystems are able to recover even after heavy disturbance by humans.
The paper is a direct challenge to the influential Planetary Boundaries thesis, which was published in Nature in 2009. There, a number of prominent scientists had suggested that the massive imprint of humanity (our agriculture, cities, carbon emissions) was overrunning the earth’s ecosystems, even pushing it past (or approaching) points of no return. Unless we got a handle on this, they said, humans would be in for quite a bumpy ride on a permanently damaged and dysfunctional planet.
The fresh critique of this assertion in a reputable journal is sure to stir debate between the two camps that have staked out their positions on the Planetary Boundaries concept. Some of that is already starting to play out.
Meanwhile, the idea of ecological and climate tipping points–the earth being pushed over a precipitous edge–has firmly taken root in environmental discourse.
Meanwhile, the idea of ecological and climate tipping points–the earth being pushed over a precipitous edge–has firmly taken root in environmental discourse.
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It’s called the hard sell, more suited to a time share sales pitch than actual science. Let cooler heads prevail. I feel kind of sorry for the study’s authors though. The eco-dogmatists are going to rip them a new one.
Well, there’s no doubt that there are well-known “tipping points” or global events: the P-Tr, K-T extinctions, for example, along with a few others among the lesser geological boundaries. These global events are extremely rare by human standards: four or five in 600 million years!
Resilience Science blog argues that consumption of ecological resources (forest and oceanic resources, for example) are worldwide interconnected events. Perhaps. But there are two corresponding questions they overlook:
ONE: are there any “tipping points” in geological history with an ecological
origin? The answer is a resounding no. To the best of our knowledge,
the major global events in the geologic record have physical origins.
Not only that, they are triggered by catastrophic
physical events: immense volcanic eruptions and asteroid impacts.
TWO: can ecological changes – say, the disruption of food chains – either cause major or even minor “tipping points”? Once again, we can turn to the geologic record. Humans clearly hunted megafauna to extinction on two continents: North America and Australia. Did these ecological changes make either continent less habitable? On the contrary, human populations continued to grow as humans found new ways to use other resources.
I seriously doubt ecological changes alone can cause even minor global tipping points. Changes in trophic chains in oceans and on land don’t change the overall biomass, nor do they seem to have a detrimental effect on human resource consumption.
The concept of tipping points has become, in the context of climate change, a refuge of its own for discussants to retreat to when normal arguments fail. It is a last bastion when other arguments are reasonably challenged. It is more or less irrefutable because it is not based on physical science or evidence. ‘Emitting CO2 is exactly like a meteor striking the planet millions of years ago.’ Umm. Okay.
Because the most active of the alarmed frequently argue themselves into a corner, the idea of tipping points offers them a Get Out of Jail Free card to be tossed on the table. We’ve seen it happen here in the comments section of this blog over the years many times.
We’ve also seen made-up ECS figures and many, many different shades of crypto-denialism masquerading as reasoned discourse, haven’t we, Tom?
That said, the ‘tipping points’ meme is perhaps prematurely tabled and so prematurely dismissed by crypto-denialists.
It will be interesting to see how ocean pH modulated by OHC affects the marine ecosystem on a planetary scale. It will also be interesting to see how tropospheric temperatures engage with the terrestrial/marine carbon sinks and the sign and magnitude of resulting feedbacks.
Let’s give it a century or so.
jh
Interesting, but I think there is a (perhaps understandable) degree of anthropocentric bias around the tipping points argument. Is it not the case that substantial reorganisations of the global ecology later this century are considered highly likely to be *inimical* to a global population of ~9bn?
“there is empirical and experimental evidence to suggest that many ecosystems are able to recover”
Come on, Keith. We all know that experimental and empirical evidence mean nothing in Climate Science! It’s all about the models!!! 😉
It is also very much the case that huge commercial gains and profits are being made in the name of ‘greening’ the environment, for examples corporations (as tax evasion) investing heavily in foreign companies building wind farms. These wind farms cost as much in CO2 heavy manufacture, transport and erection as any likely future energy production, making them very negative in overall environmental impact! It also needs to be remembered that climate change/shift has occurred many times in Earth’s history, that the oceans and unpopulated regions very vastly exceed populated areas, and fluctuations in the Sun’s output also affects our climate. If we really want to tackle any impact by people on the planet, stop most of the hundreds of thousands of flights by aeroplanes worldwide daily, reduce social (cruise) shipping and slow ships to reduce energy consumption/greenhouse gas emissions!
The vast majority of CO2 emissions are from coal fired electricity generation plant. The ‘it’s a scam’ meme is just boring. There are always scams (it’s called ‘business as usual’). The problem is *radiative physics*.
Yes, climate has changed in the past. No, this is of no relevance to abrupt warming and its ecological impacts and the net effect on a global population of ~9bn later this century.
And, no, it’s not the effing sun.
“are there any “tipping points” in geological history with an ecological origin? The answer is a resounding no.”
Don’t forget the Great Oxygenation Event, Carboniferous Rainforest Collapse, Late Devonian extinction, and Quaternary extinction (which *was* probably anthropogenic, though it did indeed work out fine for us).
I think most tipping point rhetoric is more panicky than is warranted, but it’s not pulled *completely* out of thin air.
Coal or wood fired generating plants can be made environmentally clean, just ups cost a lot! Hundreds of thousands of jet planes cause a massive and colossal. amount of pollution every day, every year.
Coal emissions reduction with CCS is a pipe-dream to this day. There isn’t a single commercial-scale demonstration plant. Not one.
Aviation contributes about 2% to anthropogenic CO2 emissions.
You appear to be poorly informed on this topic.
I think it’s worth noting that Brook et al. (that’s Barry Brook of Brave New Climate I presume) doesn’t say that the human impact on ecosystems is not real, growing and in many cases, huge:
Although there is convincing evidence that human drivers can cause
regime shifts at local and regional scales, the increasingly invoked
concept of planetary scale tipping points in the terrestrial biosphere
remains unconfirmed.
It’s more a slide into the abyss than a backflip:
By evaluating potential mechanisms and drivers, we conclude that spatial heterogeneity in drivers and responses, and lack of strong continental interconnectivity, probably induce relatively smooth changes at the global scale, without an expectation of marked tipping patterns.
Which leads to the not-that-contentious conclusion that:
This implies that identifying critical points along global continua of drivers might be unfeasible and that characterizing global biotic change with single aggregates is inapt.
Of course as the century progresses, the global effects on marine and terrestrial ecosystems from a sustained increase in the atmospheric fraction of CO2 will become more pronounced and this hypothesis will be tested.
What seems to missing here in any realistic sense of the time frames involved. Certainly ecosystems can ‘recover’ from enormous ‘traumas – they can evolve into something different than what was there before – but in the case of really serious damage, aren’t we talking about spans of time in excess of the human life span, hundreds, even thousands of years? It looks like the earth’s climate is entering a period of pronounced instability, it is impossible to predict precisely what is coming, and there is little sign that our societies are in any way prepared to deal with what is happening. Maybe it is not irreversible. Maybe we’ll only have to deal with this for a century or so. Read the subtext…it is really frightening.
Keith
To forestall Marlowe, I would like to mention the Breakthrough Institute. 😉
I had forgotten that Brook was made an honorary fellow or some such. It was seeing Blomquist among the authors that reminded me that BTI was questioning that:
Six of the “planetary boundaries” — land-use change,
biodiversity loss, nitrogen levels, freshwater use, aerosol loading, and
chemical pollution — do not have planetary biophysical boundaries in
themselves.
I disagree, the headlines are frightening, the subtext is generally not that bad.
#1. I’ll might give you that one.
#2. Cause unknown – volcanism is a good bet.
#3, #4. Extinction events are common in the geologic record. They’re not tipping points. A “tipping point” is suppose to generate a wave of ever-worse consequences, such that it eventually has dire consequences for most or all of life, especially humans. I don’t see that in the Dev or Quat extinctions.
BBD,
I guess my point is that the geologic record that suggests major destructive events (eg, tipping points) are NOT driven by ecological factors, human induced or otherwise. They seem to be driven by catastrophic physical events. I doubt that will change in this century.
Humans have already triggered a “substantial reorganization of global ecology”. We’re in the midst of, and probably the cause of, a major extinction event. I doesn’t seem to have harmed us.
What abrupt warming- 1978-1998 which was like similar warming periods in the past? Or do you have some new information? I sure agree that 9B people will have a negative impact. What do you suggest?
BBD, This is such a pseudoscientific argument you are making. Where I am sitting was 10,000 years ago buried under 5000 feet of ice. Average temperatures were 15 degrees C colder and there was NO ecosystem. After the tipping point was crossed, there is now one of the most productive ecosystems on earth. Warming will affect this ecosystem much less than that change and probably increase further its productivity. There are fewer nonlinear feedbacks from our current climate to a warmer one, e.g., ice albedo, etc. And there is increasing evidence that “its not as bad as we thought.” Ever heard of James Annon? Looks like poor statistical methods have inflated past IPCC estimates of climate sensitivity to CO2. Extreme outcomes are increasingly seen as artifacts of poor science.
Its just such bunk. Remember all the tipping points of the past. Overpopulation was supposed to cause mass starvation. Ground water in the great plains was going to run out. It’s now stabilized. Mercury was going to kill us all. AIDS was going to kill half the human race. If we go back to the progressive era, and social darwinism, there was fear of the “defective” among us debasing the human gene pool. Extreme weather is the latest one for which there is no scientific evidence even according to the IPCC. So you are in a long line of fear mongers, obsessive purity loving types who wash their hands every 5 minutes during flu season. Mankind and life are constantly changing and evolving. Remember General Jack D. Ripper and his fear of floridatio?. Checked the purity of your prescious bodily fluids recently BBD? I suggest you check it out. Danger lurks everywhere!!!
It’s always good to take note of such a theory,though. As by definition, a tipping point is irreversible. By the time it is validated it may or may not be too late. As long as the theory at least has a measurable possibility of happening.
jh
I think you may have misinterpreted the arguments here. The Brook et al. paper is really something coming our of the Breakthrough Institute, which argues against several *specific* tipping points proposed by Rockstrom et al:
Six of the “planetary boundaries” — land-use change,
biodiversity loss, nitrogen levels, freshwater use, aerosol loading, and chemical pollution — do not have planetary biophysical boundaries in themselves.
Follow the link for a very clear and readable synopsis of the BTI/Brook et al. argument.
Ever heard of James Annon? Looks like poor statistical methods have inflated past IPCC estimates of
climate sensitivity to CO2. Extreme outcomes are increasingly seen as
artifacts of poor science.
That would be James *Annan*. Of course I have. I’m even familiar with his work. Sufficiently so to be able to point out that you are misrepresenting it.
Annan demonstrates that values for ECS to 2xCO2 above 4.5C are very unlikely. The ‘fat tail’ of higher estimates is docked. This leaves us with ECS somewhere in the 2.5C – 3C range. Annan is only ‘controversial’ if you were invested in a high value for ECS or are a contrarian who has not understood that it makes no real difference to the standard best estimate: IPCC AR4 WG1 gives ~3C as the *most likely* value.
Tripe lurks everywhere!!
DY
Warming will affect this ecosystem much less than that change and probably increase further its productivity.
Argument by assertion. Okay, I assert that this is arrant nonsense. You can defend your assertion by providing several supporting references to recently published papers in mainstream reviewed climate journals. Or you can face facts: you are just saying stuff. Stuff which the experts disagree with.
peter steager
IIRC it took ~ 50Ma for something like late Permian levels of biodiversity to re-establish after the end-Permian extinction event (Sahney & Benton 2008)
Yea, but you know as well as I do that the fat tail is the “tipping point” scenario you seem to believe in. The IPCC PDF fat tail depends on the uniform prior, and its bad statistics!! See Annan’s recent blog post on this. And then there is Nic Lewis, who so far is unrefuted by anyone. Annan’s recent last glacial maximum paper estimates a linear sensitivity of 1.7K, rather less than Hansen’s inflated estimate and coincidently the same as Lewis’ estimate. Have you noticed that Schmidt, the alter boy of high sensitivity is now saying that GISS models have a sensitivity of 2.3-2.7. Their last paper said 2.7. Is he getting a preiminition that its not nearly as bad as your ilk say? And then there is a recent paper that shows that the Greenland ice sheet is a lot more stable than assumed. Apparently, no tipping point there. BBD, aside from outdated and flawed IPCC reports, what is the basis for your tipping point dogma?
Yea, the experts, they disagree. Your problem is that your meme depends on cherry picking the worst possible outcomes. You are just saying things without any scientific backing.
Yea, but you know as well as I do that the fat tail is the “tipping point” scenario you seem to believe in.
I have *always* accepted and quoted the ~3C ECS estimate in AR4.
Nic Lewis biased his result low by making a series of choices that were designed to get a low result. Worse still, his aerosol negative forcing value is *a misinterpretation* of the leaked AR5 SOD.
You need to go back to that post at Annan’s blog and read the comments. Pay very close attention to Paul S and Karsten.
Have you noticed that Schmidt, the alter boy of high sensitivity is now saying that GISS models have a sensitivity of 2.3-2.7. Their last paper said 2.7. Is he getting a preiminition that its not nearly as bad as
your ilk say?
You are laughably misrepresenting Schmidt, who has *always* rejected high ECS estimates. This sort of guff does not help establish credibility.
Your problem is that your meme depends on cherry picking the worst possible outcomes. You are just saying things without any scientific backing.
Cobblers. I’d love to see you illustrate this astonishing misrepresentation with any quotes by me you can find at CaS. Argument by assertion is bad. Argument by asserting crap is even worse.
You continue to say stuff.
Apparently, no tipping point there. BBD, aside from outdated and flawed
IPCC reports, what is the basis for your tipping point dogma?
*What* ‘tipping point dogma’? What are you talking about? Rarely have I had so many words stuffed into my mouth in one go.
And then there is a recent paper that shows that the Greenland ice sheet is a lot more stable than assumed.
Yes, so to account for Eemian MSL highstand we now need to look to the EAIS as well as the WAIS. Not good news at all.
I don’t think you really know what you are talking about.
I
That’s a matter of dispute as you well know.
You know well enough what I mean. The runaway feedbacks Hansen keeps talking about.
You of course didn’t respond to the point I made which is that newer estimates are going lower and that the IPCC numbers are high because of uniform priors. If you really were familiar with Annan’s work, you would know that. Nic Lewis did a pretty good job of defending his choices at Real Climate and other places. So far no response from The Team. GISS’s climate sensitivity has likewise been trending down, just as I said and you didn’t answer except to call me names. As for your stubborn defense of inflated estimates, you said:
“We’ve also seen made-up ECS figures and many, many different shades of crypto-denialism masquerading as reasoned discourse, haven’t we, Tom? That said, the ‘tipping points’ meme is perhaps prematurely tabled and so prematurely dismissed by crypto-denialists.”
I guess name calling is your speciality. The recent scientific work is tending to make the tipping point scenarios very unlikely. A lot of these things were due to faulty statistics, not the first time in climate science. Need I mention the Mannian fantasies recently debunked in the statistics literature. Climate scientists seem to rigorously reject disagreement in the journals they edit or referee for. But I guess Climategate didn’t happen according to you.
The point is that the weight of scientific evidence is showing that the extreme and disastrous scenarios routinely trotted out by people like Hansen are simply not going to happen. You can continue to deflect this point by name calling. It is unconvincing and not worthy of a man with I’m sure a sterling scientific reputation like yourself, who uses the handle BBD (nicknamed Blah Blah Duh) in other forums.
David Young:
You of course didn’t respond to the point I made which is that newer estimates are going lower and that the IPCC numbers are high because of uniform priors.
AR4 best estimate: ~3C
Annan: ~2.5C
Hansen (GISS ModelE) ~2.7C
Jim ‘Crazy Train’ Hansen and Annan both go low. Amazing. Policy implications vs ~3C? None.
There are various possible outcomes dependent on emissions and concomitant RF. Hansen’s argument is that if the atmospheric fraction of CO2 rises above ~550ppmv, warming will be greater than 2.5C – 3C and this will be a Bad Thing.
Which seems entirely reasonable.
Schmidt’s latest for GISS is 2.3-2.7. Hedging his bets. You of course don’t respond to Nic Lewis or Annan’s LGM paper. Hansen 1988 was actually 4.2. Do you see a historical trend here? Also you didn’t respond to the point that the IPCC estimates are biased high by bad statistics.
Hansen has had so many arguments, its hard to keep track of all of them. Clearly, his 1988 calculations were wrong. And it looks like the models (which are by the way the basis for IPCC attribution and senstivity) have failed to predict the historical record. To say otherwise is rather original but wrong. Hansen is clearly an activist and that does detract from the objectivity of his science.
In any case, there is little evidence that doubling CO2 will result in disaster. There is a lot of evidence of gross exaggeration by climate scientists that happens to support their political or pseudo religios (Green) points of view.
No, didn’t miss the argument.
We can approach scientific problems empirically or theoretically. Theory is a poor way to approach “Earth System” problems. Normally, theory is developed from and validated with repeated empirical tests. This can’t be done with Earth System problems. That renders theory much less useful.
Geological history offers us the only way to approach “tipping point” problems empirically – where we can actually see the result.
Geologic history suggests that major ecological, and even major chemical changes, do not generate tipping points.
Hmm. This one is remarkable, even for you. DY considers the ecological change at a certain location between the depths of the ice age to today and asserts that this is bigger than the change between today and a hundred years hence (or whenever). And you consider this “arrant nonsense” and “stuff which the experts disagree with”?
What experts think the warming will create a greater change than that between the ecological zero of ice-scraped rock in the pitch dark 5,000 feet down and today?
It would, in any case, be easy to tell, even without your Appeal to Orthodox Authority. Simply travel a hundred miles south, and report on whether the ecology is more or less productive there, and to what degree.
Geologic history suggests that major ecological, and even major chemical changes, do not generate tipping points.
Nope. You miss the point entirely with what looks increasingly like a deliberate strawman.
Let’s start of with a reminder that the ‘canonical’ ECS estimate from AR4 is the range 2C – 4.5C with a most likely value somewhere around 3C. Values *above* 4.5C are considered *unlikely*. Constantly claiming that the IPCC estimates are ‘biased high by bad statistics’ is – at best – a strawman.
GISS ModelE doesn’t ‘hedge bets’ for anyone. I get the strong impression that you don’t understand that the sensitivity of this simulator is an *emergent property* not a parameter. Hansen’s pioneering work back in 1988 was good for its time. In the decades since, Hansen has worked to *better constrain* the estimate for ECS. Again, you are engaged in furious strawmanning. It’s tedious.
Annan and Hargreaves estimate a LGM of ~2.5C. Big deal. We’ve already been through this. It makes no practical difference if ECS is nearer 2.5C than 3C. Also, the A&H LGM estimate is problematic, much like Schmittner et al. (2011). MARGO SST (especially equatorial SST) is biased warm so the A&H estimate of S is biased low. You haven’t got a clue about any of this, have you?
I’ve already told you that Lewis’s stuff is flawed, and briefly explained why as well as pointing you to the discussion at Annan’s blog where you can inform yourself on the detail. Instead, you continue to repeat yourself, which is tedious.
There is a lot of evidence of gross exaggeration by climate scientists that happens to support their political or pseudo religios (Green) points of view.
This is fantasy. Pure right-wingnut tripe. Can you back this up? No, you can’t. You are just *saying stuff* again.
Trying to help out the clueless wingnuts again nullius?
Lie down with dogs…
“…, they’re better than weasels.” That’s how the saying goes, isn’t it?
But seriously, did you hear that heartwarming story of the little Polish girl who got lost in the snow and was saved by her dog?
Children just aren’t going to know what snow is…
But thanks to your tireless efforts, they will be well-acquainted with disingenuous BS!
It must be bizarre, being you. In the real world, I have no doubt your tolerance for idiots is limited. Yet here, you routinely take their part!
Politics makes for strange bedfellows, eh?
I don’t think of it as tolerance for idiots, but as tolerance for people.
Everybody is a complex mixture – an ‘idiot’ about some things, an expert at others. I try not to judge, because I know my own breadth of expertise and experience is limited too. That’s where we get the tribalism – when we start to label people as just one thing because they think differently from ourselves.
I will grant you that in this case as far as I can see DY started the name-calling first. I’m not criticising. There’s certainly a place in life for a bit of fun with knock-down insult-hurling custard-pie-fights, when the people you’re playing with enjoy it too. But I think it helps to maintain a sense of perspective and humour about these things. And to push people to think beyond the labels.
I even enjoy my conversations with you – and as you probably know, not everyone tolerates that! Talking to people who think differently and trying to understand where they’re coming from – even if you’ll never agree with them – broadens the mind. It is a training in mental flexibility, in paradigm shifting, in seeing things from all viewpoints. Intellectual tolerance is not just a moral or political stance, but is a matter of self-interest too. So why wouldn’t I wouldn’t practice it in “real life” as well?
If you come across something new and ‘bizarre’ in life, don’t you just get an urge to try to understand it?
If you come across something new and ‘bizarre’ in life, don’t you just get an urge to try to understand it?
That’s what brings me here, nullius!
😉
Blah Blah Duh, The central point of Annan’s and Lewis’ critique of the IPCC is based on the biases introduced by uniform priors. You are either ignorant or don’t care to know the truth. Uniform priors on S are particularly bad and they are used in all the AR4 sensitivity studies. They even recalculated one that didn’t use this prior. Annan is particularly harsh in his criticism. Can’t you read or when you read a blog post, do you only select those things that support your position?
I of course do know about sensitivity and how it emerges from climate models. I have 32 years of experience in computational modeling of these things and you have how much? Blah Blah Duh.
The GISS range I gave came from the Real Climate discussion of sensitivity where Nic Lewis joined in. No effective refutation of Lewis there.
I participated in the discussion at Annan’s blog where Lewis discussed his estimate. I saw no effective refutation. KarSteN, it turns out is a postdoc specializing in aerosols and after much Blah Blah Duh type protestations, merely confirmed that we know very little about aerosols and that he could not answer the most elementary quesitons about their distributions or their effect on local temperatures. The argument about aerosol forcings in AR5 SOD was never definitively settled.
If you look in Annan’s latest LGM paper, you will see a linear sensitivity of 1.7K. There are uspecified nonlinear effects that they say will increase that if its a response to CO2. No real numbers or calculations that I saw anyway.
Exaggeration like Hansen’s 1988 testimony in which he tried to imply that a business as usual scenario would result in 3 times the warming by now we have actually had. Now don’t give me the lie that actual forcings are less than that. Hansen based it on emissions, not on forcings.
You, Blah Blah Duh, so far as I can see have no actual experience in science but are quite good at hiding behind your tag. If you have any credentials that should cause me to take you seriously, please show them. Otherwise, you are just another activist who I will ignore in the future.
DY
Blah Blah Duh, The central point of Annan’s and Lewis’ critique of the IPCC is based on the biases introduced by uniform priors. You are either ignorant or don’t care to know the truth.
My screen name is BBD, you red-bottomed and pink-lipped lesser-spotted buffoon 😉
See? What you are doing here doesn’t really advance the discussion.
Now, back to grown-up land. Best estimate for ECS is still ~2.5C – 3C, which makes no substantive difference to the boring old message:
There are various possible outcomes dependent on emissions and concomitant RF. Hansen’s argument is that if the atmospheric fraction of CO2 rises above ~550ppmv, warming will be greater than 2.5C – 3C and this will be a Bad Thing.
You can bluster and ignore until your ears fall off ‘David Young’! Nothing changes 😉
And you got your arse handed to you at Annan’s 😉
Absolute rubbish. James said that my main suggestion had some merit. KarSteN simply didn’t respond. He was likewise unwilling to reveal his identity, but a helpful blog commenter found him.
So still no comment on any qualifications that you might have.
I would argue that the difference between 2C and 3C is significant. If its 1.5C or even lower, that is also significant. Climate is always changing and adaptation is always the best policy, that was the case 24,000 years ago and it is the case now.
Still no comment on the use of uniform priors. Did you not read Annan and Lewis and Jewson? If you disagree, you can try to persuade them. Perhaps they too would not take you seriously.
My belief is that you are an activist with no particular scientific credentials who is paid to frequent blogs to parrot the IPCC line and make personal attacks against skeptics. Prove me wrong, Blah Blah Duh! I would be only too happy to treat you with respect if there was even the vaguest reason to do so.
Bish, While I appreciate your conciliatory tone, I would note that BBD (whatever his name really is) started the name calling. You will the “denialist” label pulled out in the second comment on this thread. I still have no reason to take BBD (Blah Blah Duh) seriously. We all know your credentials and your track record in the climate debate. That at least makes it possible to respect you. BBD is part of the Web Hub Telescope clique whose sole purpose seems to be to insult skeptics and misrepresent their positions and their qualifications. They seem to offer nothing original and have no discernible qualifications.
Absolute rubbish. James said that my main suggestion had some merit. KarSteN simply didn’t respond. He was likewise unwilling to reveal his
identity, but a helpful blog commenter found him.
You live in a parallel universe filled with self-serving nonsense. Remember *how* that other commenter ‘found’ Karsten? And yes, you got your arse handed to you. I was there, remember?
Claims about qualifications are unverifiable and therefore meaningless. Those demanding them are *invariably* bluffers who are losing technical arguments and flailing desperately. It is obvious from the totality of this exchange who is struggling with the technical detail.
You can argue until your ears drop off, but the practical difference of ECS nearer 2.5C than 3C is negligible. You implicitly assume that CO2 will magically stabilise at ~550ppmv. Without policy intervention? Hmm?
Still no comment on the use of uniform priors.
Still zero evidence that you have either read or understood my comments here. Either you are struggling with the technical detail or living in a parallel universe 😉
My belief is that you are an activist with no particular scientific credentials who is paid to frequent blogs to parrot the IPCC line and make personal attacks against skeptics.
I do it for free and for fun. You are not a sceptic. You are a denialist buffoon. Let’s not drift off into a parallel universe.
God forbid, but if you must respond further, concentrate your wits on this:
There are various possible outcomes dependent on emissions and concomitant RF. Hansen’s argument is that if the atmospheric fraction of CO2 rises above ~550ppmv, warming will be greater than 2.5C – 3C and this will be a Bad Thing.
Again: how does CO2 magically stabilise at or below ~550ppmv without policy intervention?
Demonstrate that you can read, respond cogently to key points and generally have a clue.
Hope springs eternal 😉
Blah, Blah, Duh, I will try to respond in an adult manner to someone who apparently misrepresents what I have said here and elsewhere and seems rather ignorant of actual technical details other than parroting IPCC doctrine, namely that the central value for sensitivity is 3 C and anything over 2C is dangerous.
I believe the IPCC figures are inflated by a number of factors and have other serious problems.
1. AR4 used uniform priors which inflates the numbers especially the high tail.
2. The observationally based studies used are now obsolete and Nic Lewis has redone one of them based on more up to date estimates of forcings and using a more realistic prior. James Annon seems to agree with the point about uniform priors. On his blog, one commenter was able (by making other assumptions) to come up with a 2.5C estimate from Nic’s calculations. The issue of who is right is still open. There has been no convincing rebuttal to Nic’s calculations in my opinion.
3. The models also play a great role here being the basis of attribution and also sensitivity estimates. I know that the models are highly questionable. There is the matter of the tropospheric hot spot. Your misrepresentation of this issue notwithstanding, (the paper you refered me to elsewhere agree with me that the hotspot was not there). There is the matter of numerical error which is admitted by even the modelers to be orders of magnitude larger than for weather models because of spatial resolution. Now I have been over and over again on other threads the “dogma of the attractor” and the fact that it is almost certainly false as demonstrated for example by Paul Williams and virtually every rigorous mathematical analysis. Heard of Gerry Browing? He actually proves things, perhaps a novel concept for you.
4. There are the obvious errors such as the Himalayan glacier estimate and others having to do with malaria for example. These are just errors. I distrust alarmism because of its very long history of complete error and terrible predictions. All such claims of doom and gloom have so far proven false since the beginning of human history.
5. The paleoclimate evidence is totally different than represented by the IPCC. The Mideval warm period was probably as warm as today and earlier warm periods even warmer. What caused these changes? Mann has poisoned the well here with his poor science.
I actually think there is a good chance that sensitivity is between 1C and 2C based on the history of the estimates coming down for example for GISS and several recent calculations. There are other factors that can totally change our understanding, for example indirect solar forcings that are not in models now. Even Trenberth acknowledges some of these other factors that models do not include.
Your other point about 550 PPM is in my view an artificial limit. Why does this limit matter and what’s the evidence for it? What we need is better understanding and not more advocacy.
You are just a slime artist and a propagandist when you accuse people of being “deniars.” I do not deny radiative physics. I don’t deny any science. Science requires skepticism to advance. Acolytes are merely a hindrance.
The reason I think you are an activist with little regard for the truth is that everything said above is clear from pervious blog threads to which you have been privy. But I guess you have a short memory and an even shorter temper. Perhaps that’s why you are moderated at other blogs. Do you learn from experience?
As to qualifications. If you are in fact a smear artist (evidence provided above) then I don’t trust much you say. My credentials are easy to look up for someone of your undoubtedly superior intelligence. I have rigorous reasons for what I have been saying and a track record of rigorous mathematical modeling. I would normally blush to say this, but with you truth is more important than modesty. The reason I ask for your credentials is that my experience is that you say nothing new or original but merely parrot things you see on blogs or possibly read in the literature, but nothing of a mathematical or rigorous nature. If you don’t care to be more forthcoming, then you are what you appear, an anonymous activist with too much time on your hands.
I am quite wiling to leave this matter to the people who have read comments from both of us, but you are a clearly a waste of time. I evaluate people by their credentials and their track record. I value the contributions (and have said so) from others who I respect such as Andy Lacis and Richard Muller for example who disagree with me. I value their contributions. You are in a different league.
One other critical point. Climate is always changing. As in the past, the most effective thing to do is to adapt. Change can bring opportunities as well as dangers. The change from the ice age to the Holocene optimum was almost wholly good for human beings, despite huge sea level rise and extreme changes at high latitudes. A somewhat warmer world will not make nearly so much difference as that. Our exploitation of fossil fuels has had almost wholly beneficial consequences. Poverty, disease, and war are quite real and immediate dangers that must assume a high priority for our species and for science. Any careful analysis of costs and benefits must take that into account.
David
Ah, the denialist tropes flow thick and fast in your discourse, oh lesser spotted buffoon!
Where to start?
How about with your classic ‘climate is always changing’ meme. Indeed it is, and indeed the Holocene has been kind to humanity. This is to ignore the potentially devastating impacts of abrupt warming and climate disruption on a projected population of ~9bn later this century. We can think in terms of agricultural impacts and the global food supply *alone* if you wish.
You continue with the desperate strawmanning. As you must since it turns out that your right-wingnut, conspiracy theory about the ‘biased’ IPCC ‘over-estimate’ fizzles out in the face of the facts: the IPCC best estimate is 2C – 4.5C with a most likely value of ~3C. Annan (sp!!) and Hargreaves LGM estimate for S is ~2.5C. Nic Lewis’s deliberately skewed analysis ‘published’ as a guest post on a denier blog (BH) is contrarian mischief-making and will be ignored unless/until published in a reviewed mainstream climate journal with correctly constrained estimates – especially for aerosol negative forcing.
***
Once again, in the face of your relentless attempts to argue something that isn’t there, I am forced to repeat myself:
“There are various possible outcomes dependent on emissions and concomitant RF. The mainstream position is that if the atmospheric fraction of CO2 rises above ~550ppmv, warming will be greater than 2.5C – 3C and this will be a Bad Thing.”
As I *knew* you would, you have *skipped over the crucial bit*: how does CO2 magically stabilise at or below ~550ppmv without policy intervention? Hmm? Deal with this instead of denying it, please.
More conspiratorial, politicised anti-IPCC nonsense. There was no ‘Mediaval Warm Period’ in the sense that you imagine. There was no global and synchronous warming event. Instead there were several regional and discontinuous warming events, mainly in the NH, spread over a period of ~400y. There is exactly no evidence that global average temperature matched that of the late C20th. And if it had, this would imply that the climate was indeed rather sensitive since there’s no evidence of a major forcing change at the time. You are riffing on another classic conspiracy/denier meme. Big yawn.
Only someone with an impoverished understanding of the topic could claim that S is between 1C and 2C. Paleoclimate behaviour effectively sets the lower bound at ~2C (and most researchers agree that ≥ 2.5C is far more likely based on paleoclimate behaviour from the LGM right back across the Cenozoic.
In summary, who cares what an ill-informed, unpleasant conspiracist with blatantly politicised views ‘thinks’? Get it written up and published in a reviewed journal if you want to have a hope of being taken seriously. Demonstrate these impressive scientific skillz you repeatedly hint at. Otherwise you will be regarded by default as a politicised conspiracist bluffer venting their fear, mistrust and denial in blog comments 😉
DY
Are you David M. Young of CSM/SEAPAC?
and earlier warm periods even warmer. What caused these changes?
Orbital dynamics. Specifically precession during the misnomered Holocene Climate Optimum (itself spatially and temporally heterogenous). Get a clue.
Our exploitation of fossil fuels has had almost wholly beneficial consequences.
Up until now. Going forward, this seems very unlikely to continue to be the case. You may well be a modeller of some distinction in a field other than climate, but you bring a mash of misconceptions and politically motivated argument (downright conspiratorial ideation, much of the time) to the table here. And you are offensive with it.
Fair warning: you are picking on the wrong commenter.
Your bigotry is showing, Blah Blah Duh. Of course that is not me. Hint: real publication record of relevance to climate. You not only have a short memory but are terrible at research. The only reason you might think it was me is your tin foil hat conspiracy theories and your total ignorance. You are beneath contempt. Good bye and good riddance to the most slimy person I’ve ever dealt with on the web.
FOO Young said:
” BBD is part of the Web Hub Telescope clique whose sole purpose seems
to be to insult skeptics and misrepresent their positions and their
qualifications.”
The clique is people interested in environmental modeling. It’s always about simplifying the arguments to make them more understandable:
http://theoilconundrum.blogspot.com/2013/03/climate-sensitivity-and-33c-discrepancy.html
The converse of this is of course to call out the ones that seek to spread FUD.
Bluffer!
Mr. Fuller, both CO2 emissions and the meteor/asteroid strike(s) are measurable facts. What are you saying in this sentence?