Guest Post by Willis Eschenbach
One of the arguments frequently applied to the climate debate is that the “Precautionary Principle” requires that we take action to reduce CO2. However, this is a misunderstanding of the Precautionary Principle, which means something very different from the kind of caution that makes us carry an umbrella when rain threatens. Some people are taking the Precautionary Principle way too far …
Figure 1. Umbrella Exhibiting an Excess of Precaution
The nature of the Precautionary Principle is widely misunderstood. Let me start with the birth of the Precautionary Principle (I’ll call it PP for short), which comes from the United Nations Rio de Janeiro Declaration on the Environment (1992). Here’s their original formulation:
“In order to protect the environment, the precautionary approach shall be widely applied by States according to their capability. Where there are threats of serious or irreversible damage, lack of full scientific certainty shall not be used as a reason for postponing cost-effective measures to prevent environmental degradation.”
This is an excellent statement of the PP, as it distinguishes it from such things as carrying umbrellas, denying bank loans, approving the Kyoto Protocol, invading Afghanistan, or using seat belts.
The three key parts of the PP (emphasis mine) are:
1) A threat of serious or irreversible damage.
2) A lack of full scientific certainty (in other words, the existence of partial but not conclusive scientific evidence).
3) The availability of cost-effective measures that we know will prevent the problem.
Here are some examples of how these key parts of the PP work out in practice.
We have full scientific certainty that seat belts save lives, and that using an umbrella keeps us dry. Thus, using them is not an example of the PP, it is simply acting reasonably on principles about which we are scientifically certain.
There are no scientific principles or evidence that we can apply to the question of invading Afghanistan, so we cannot apply the PP there either.
Bank loans are neither serious nor irreversible, nor is there partial scientific understanding of them, so they don’t qualify for the PP.
The Kyoto Protocol is so far from being cost-effective as to be laughable. The PP can be thought of as a kind of insurance policy. No one would pay $200,000 for an insurance policy if the payoff in case of an accident were only $20, yet this is the kind of ratio of cost to payoff that the Kyoto Protocol involves. Even its proponents say that if the states involved met their targets, it would only reduce the temperature by a tenth of a degree in fifty years … not a good risk/reward ratio.
Finally, consider CO2. The claim is that in fifty years, we’ll be sorry if we don’t stop producing CO2 now. However, we don’t know whether CO2 will cause any damage at all in fifty years, much less whether it will cause serious or irreversible damage. We have very little evidence that CO2 will cause “dangerous” warming other than fanciful forecasts from untested, unverified, unvalidated climate models which have not been subjected to software quality assurance of any kind. We have no evidence that a warmer world is a worse world, it might be a better world. The proposed remedies are estimated to cost on the order of a trillion dollars a year … hardly cost effective under any analysis. Nor do we have any certainty whether the proposed remedies will prevent the projected problem. So cutting CO2 fails to qualify for the PP under all three of the criteria.
On the other side of the equation, a good example of when we should definitely use the PP involves local extinction. We have fairly good scientific understanding that removing a top predator from a local ecosystem badly screws things up. Kill the mountain lions, and the deer go wild, then the plants are overgrazed, then the ground erodes, insect populations are unbalanced, and so on down the line.
Now, if we are looking at a novel ecosystem that has not been scientifically studied, we do not have full scientific certainty that removing the top predator will actually cause serious or irreversible damage to the ecosystem. However, if there is a cost-effective method to avoid removing the top predator, the PP says that we should do so. It fulfils the three requirements of the PP — there is a threat of serious or irreversible damage, we have partial scientific certainty, and a cost-effective solution exists, so we should act.
Because I hold these views about the inapplicability of the precautionary principle to CO2, I am often accused of not wanting to do anything about a possible threat. People say I’m ignoring something which could cause problems in the future. This is not the case. I do not advocate inaction. I advocate the use of “no-regrets” actions in response to this kind of possible danger.
The rule of the no-regrets approach is very simple — do things that will provide real, immediate, low-cost, tangible benefits whether or not the threat is real. That way you won’t regret your actions.
Here are some examples of no-regrets responses to the predicted threats of CO2. In Peru, the slums up on the hillside above Lima are very dry, which is a problem that is supposed to get worse if the world warms. In response to the problem, people are installing “fog nets“. These nets capture water from the fog, providing fresh water to the villagers.
In India’s Ladakh region, they have the same problem, lack of water. So they have started building “artificial glaciers“.These are low-cost shallow ponds where they divert the water during the winter. The water freezes, and is slowly released as the “glacier” melts over the course of the following growing season.
These are the best type of response to a possible threat from CO2. They are inexpensive, they solve a real problem today rather than a half century from now, and they are aimed at the poor of the world.
These responses also reveal what I call the “dirty secret” of the “we’re all gonna die in fifty years from CO2” crowd. The dirty secret of their forecasts of massive impending doom is that all of the threatened catastrophes they warn us about are here already.
All the different types of climate-related destruction that people are so worried will happen in fifty years are happening today. Droughts? We got ’em. Floods? There’s plenty. Rising sea levels? Check. Insect borne diseases? Which ones would you like? Tornados and extreme storms? We get them all the time. People dying of starvation? How many do you want? All the Biblical Plagues of Egypt? Would you like flies with that?
Forget about what will happen in fifty years. Every possible climate catastrophe is happening now, and has been for centuries.
So if you are truly interested in those problems, do something about them today. Contribute to organizations developing salt resistant crops. Put money into teaching traditional drought resisting measures in Africa. Support the use of micro-hydroelectric plants for village energy. The possibilities are endless.
That way, whether or not the doomsayers are right about what will happen in fifty years, both then and now people will be better prepared and more able to confront the problems caused by the unpleasant vagaries of climate. Fighting to reduce CO2 is hugely expensive, has been totally unsuccessful to date, will be very damaging to the lives of the poorest people, and has no certainty of bringing the promised results. This is a very bad combination.
Me, I don’t think CO2 will cause those doomsday scenarios. But that’s just me, I’ve been wrong before. If you do care about CO2 and think it is teh eeeevil, you should be out promoting your favorite no-regrets option. Because whether or not CO2 is a danger as people claim, if you do that you can be sure that you are not just pouring money down a bottomless hole with very poor odds of success. That’s the real Precautionary Principle.
Skeptical Skeptic.
Even if we stipulate that the earth is warming and it’s caused by human activity, that doesn’t get us very far. See my posting of 02:07:32 above.
>>>The first says that most of the run-off never reaches the city storm drains anyway because it’s just absorbed into the soil. The other study says precisely the opposite: that too much of Colorado’s run-off reaches the storm sewers, resulting in sewage back-ups and inundation of the water purification systems with herbicides, fertilizers and other materials flushed out of the soil by sudden downpours<<<
Now that I think about it a little more… The water goes from my roof into my tank. From my tank it gets used and goes into the drain, which goes to the septic system. From the septic system it goes… into to the ground!
Voila, (see I really am French!) It goes to the same place after all!
Dear Skeptical Skeptic,
When you are a little older you will realize that “experts” aren’t all they are cracked up to be. I realized this when I had to deal with “expert” lawyers, and “expert” accountants and “expert” financial planners when dealing with my mother’s estate. These are supposed to be professionals and the advice they gave me, and expected me to pay for was often wrong and would have cost me sums of money many times larger than their fees. They did not care. It was not their money. Ultimately, I had to research and learn for myself the truth. I had to seek information in many and varied places to be sure. Nevertheless, in the end, the truth ultimately asserts itself. Always, be skeptical.
Bon chance.
“Skeptical Skeptic” – is that like a double negative? Real AGW skeptics of the so-called science come here because we don’t think a person’s affiliation or credentials or where he or she publishes – or even the consensus of thousands of such individuals – confers truth to certain claims. The only way to make a dent here is to engage in the analysis of the science, issue by issue.
aber (02:31:35) :
….. but the precautionary principle (PP) needs to be applied on a global level with regard to the oceans.
I’m in full agreement with you here. The Precautionary Principle is a dangerous thing in many cases, as shown by Willis – excellent analysis – but in the oceans it would supplant another politically and socially charged approach to the exploitation of nature: the principle of “maximum sustained yield” – which argued that if humanity did not maximize its exploitation of resources at the peak level of sustainability, then fish or other resources would be ‘dangerously’ wasted. The problem with ocean resources – especially the renewables such as fish – is that they’re hard to see and hard to quantify, so the mythical point of MSY was always surpassed, with disastrous consequences for fish stocks. But nobody has figured out how to reconcile the MSY with the precautionary principle…
RE: Truth seeker
I’m pretty sure the link is http:/brneurosci.org/co2.html – I really want to throw this mobile in the toilet… Who makes a “smart phone” that can’t copy and paste. Worse comes to worse google CO2 ir absorption saturation and it’s the first link. It’s more of an overview article and doesn’t go in depth, and I ran across a pro-AGW article (4th down in the search results maybe) that indicated that even if the CO2 wavelengths were completely absorbed, more CO2 would still make more warming(?)
So tell me Skeptical Skeptic , how do you see mankind in the near future? What kind of world would you like to see?
RE: DirkH
Thanks for sharing your notes – great stuff!
Indur M. Goklany (19:41:58) : ..there is a precautionary principle that is explicitly included in the UN Framework Convention on Climate Change (UNFCCC), but it is often ignored by environmentalists because it implicitly endorses cost-benefit analysis…
“Environmentalists”, so called, because they pretend they have the sole right to be concerned about our environment and be the sole caretakers of it, often with little or no education in science, no idea about cost-benefit analysis, and very little about economics, whole heartedly endorse things like cap n trade, carbon tax and CO2 sequestering. Many would rejoice in human catastrophe as a fitting moral punishment for their evil ways. They have a belief system that will in no way be affected by logic or facts.
Commercial insurance companies surely work out risks using probabilities and customers could work out the worth of the insurance using cost benefit analysis. By that analysis, the economic measures proposed above seem to have huge cost for little or no benefit.
The mainstream media is actively conniving to destroy our freedoms, among them the freedom of speech and expression. They actively collude with extremists of all colours to twist the truth and suppress criticism.
Here I would like to note a significant event – the shooting of a Somali extremist who tried to attack the Danish cartoonist.
My only regret is the man was not delivered to paradise.
Re: Richard (Jan 1, 2010 at 22:26:53) : …”no idea about cost-benefit analysis”
Even if they (“Environmentalists”) did comprehend cost-benefit analysis, the question remains:
Whose benefits, and whose costs?
It is correct as someone said above that the ‘precautionary principle’ is in fact Pascal’s wager. The logic is exactly the same.
It rests on the true proposition that the expected value of an outcome is its probability times its cost or return. So for example, the expected value of an event which will pay off 10.00, if it has a 50% chance of happening, is worth 5.00. That is what a rational person to whom the distribution of expected values is not important should pay for it. He should pay the same for an event which pays 20.00 and which has a 25% chance of happening.
Pascal now used this fact to consider the implications of belief in God, and in particular the Christian religion. The consequence of rejecting this, should it be correct, is eternal damnation. This is a very very large payoff. The probability, he argued, might be very small, even vanishingly small. The expected value will nevertheless be huge. The argument is essentially that there is no probability so low that the expected value will be low enough for a rational person to take the chance of disbelief.
To see that the argument is fallacious, notice that it assumes that there are two alternatives, belief or disbelief. The same logical situation characterizes the use of the ‘precautionary principle’ in climate discussions: the assumption is always that we face a choice between ‘action’ and inaction. It is assumed that action is well defined, its carbon emission limitation.
The argument however, as used, provides no way of discriminating between multiple alternatives, which is the real situation. In religion, we face a choice between being eternally dammed for not accepting Christianity, but also face the same thing for not accepting Islam. Most religions (though not all) forecast some form of eternal doom if one does not accept them. So the issue is not whether to belief in God, it is rather which God to believe in, and here you notice that not all Gods are the same, but that the principle appears to suggest that the payoff from believing in several different incompatible Gods is identical. Which really does not help the seeker after salvation one bit.
We see the same thing in climate. There are a variety of things we might do which have a bearing on climate and its evolution, including adapt, ignore, wait and see….and so on. The ‘precautionary principle’ does not tell us which of these are correct, and can be used to justify any of them. If the chances that adaptation measures taken early will save human civilization, then surely we should take them, however small the chance, and however much they cost, because the payoff is so huge. Consider the question of firing huge amounts of sulphur into the stratsophere. If there is only a very tiny chance that will save civilization on earth, we surely ought to do it? Perhaps standing on our heads every morning will save civilization? Maybe if we all wore black turtleneck sweaters and bowed in prayer to Cupertino every morning? Why should we not all pray in unison ten times a day, if it has any potential, however small, to avert the wrath of God and having Him burn up the planet?
We can think of large numbers of alternatives, posit a very low but positive probability that doing them will in some way save the planet, and then conclude that they are all justified. Let us say we argue, as some have done, that to launch a nuclear first strike at a nation bent on acquiring and perhaps using nukes has any chance at all of preventing nuclear Armageddon, surely we should do it? You can all think of truly idiotic military and social proposals which can be justified by the same line of argument.
The admission of the precautionary principle as a valid way of assessing social policy thus leaves us exactly where we were before we started out. We have huge numbers of competing proposals, resources mean we cannot do them all, they all have different costs and paybacks, and the PP gives us now way of choosing between them, just as Pascal’s Wager gave us no way of deciding which religion to adopt.
This is because the PP is not a logical method of arguing, but a rhetorical device to attempt to compel an emotional assent to one particular alternative. Its problem is, it proves too much. It justifies just about any harebrained scheme one likes to think of. There is no substitute for getting down to business, calculating the real probabilities costs and benefits of proposed policies, and until you have a reasonably decent idea why you are doing things, being very careful indeed, they may just make the situation worse. The fact that they have been justified by the PP means that there was little other real justification, so the chances of this last are high.
I prefer the 7 P Principle over the Precautionary Principle.
Proper Prior Preparation Prevents Piss Poor Performance
The first place I encountered it was in a book titled “Jason Cosmo”, quite hilarious. (The unwitting protagonist, Jason Cosmo, is appointed a “Hero” by He Who sits on the Porch.)
http://en.wikipedia.org/wiki/7_Ps_%28military_adage%29
Indur M. Goklany (19:41:58)
Indur, thank you for your comments. For those who do not recognize the name, Dr. Goklany is one of the more reasonable scientific authors on a host of subjects. I have not read his book on the Precautionary Principle (available here), but the work of his that I have read I would describe as middle-of-the-road, well-balanced and reasonable. I have disagreed with some of his analyses, but they are always thought-provoking.
Best regards,
w.
vigilantfish (20:47:33) : edit
I know this is not the subject of the thread, but please allow me a small digression to discuss this. As someone who spent a good chunk of his life as a commercial fisherman (US West Coast and the Bering Sea, doing salmon trolling and gill netting, albacore bait fishing, lampara netting off of Monterrey’s Cannery Row, and herring gill netting and seining), I would say you are partially correct.
Sustainable yield is the issue, and for some fish species this is not too hard to achieve. For example, there is a long-standing and still vibrant fishery for roe herring in both San Franciso Bay and Togiak, Alaska. I have fished both, and I can assure you that they are both very closely watched and professionally managed. The same is true of the salmon gill-net fishery based out of Bristol Bay in Alaska. In the early part of the season when the salmon weren’t around in numbers, we would not be allowed to fish at all. When they show up, Fish and Game biologists count how many salmon are going up the river (the escapement). When a certain number of fish had gone up the rivers, we would be allowed six hours to fish … and that might be it for a week or two. Only after the escapement reached the total number the biologists figured was enough to keep the run healthy (plus some) were we set free to fish, and even then only Monday through Friday. The runs there are strong to this day.
Other species are much more problematic for a variety of reasons. The main one is that the migratory fish like tuna don’t know about national boundaries, or they may be found outside of the boundaries in the open ocean. This makes it very difficult to manage them, as there will be a number of countries involved … and we all know how well countries manage shared resources.
Other fish may be slow growing, so they are inherently vulnerable. Others may be hard to count, so we are operating blind. And salmon and other anadromous fish, because they live in the ocean but can only spawn in the rivers, are very vulnerable to the degradation of their inshore habitat.
Finally, the ocean is not like the land, in that the oceanic predator/prey numbers tend to cycle wildly. A wolf has half a dozen pups, a deer has one or two fauns. This means that the total numbers of either one can’t increase much in a few years. In the ocean, both predators and prey often lay hundreds of thousands of eggs. If conditions are favorable for one or the other, the next few years will see a huge shift in the population of that species. This large population variation makes it very hard to determine the effect that human fishing is having on the fish stock.
So while you are generally correct that some species are overfished, it is not because fish biologists are not aware of the problem or are not working at doing the right thing. It is often because of the inherent difficulty of managing fish stocks for a host of reasons. We’re getting better at it … but there is still a long way to go.
One problem that would not be too hard to solve is that we generally have a size limit on catching fish, where fishermen (and fisherwomen, the entry of women into the fleet was a huge and beneficial change that occurred in my youth) have to throw back the small fish. This is backwards, as there are generally lots of immature fish, while there are many fewer of the larger sexually mature fish. So we’re taking the wrong fish out of the sea, we’re killing the fish who will spawn the next generation.
There is some motion on this front, such as the “slot limit” on the Kenai River in Alaska where I was a sport fishing guide in 2005. The slot limit prevents fishermen from taking fish which are big, but not trophy sized. You can keep fish smaller or larger than the “slot”, but not those big but not trophy fish. So we’re getting there. Slowly.
But I digress … we now return you to your regularly scheduled programming.
Skeptical Skeptic, I trust science because it is self-correcting. You must also accept that science is self-correcting, if you trust science. (If you say science is not self-correcting, then science will be full of error. If you say science always gets it right without correction, then science is omnipotent and religious.) So then, science is self-correcting.
To bring this from the abstract to the real world, we need to make this empirical. What empirical evidence do you have for the variables and factors which affect the speed at which a science can and will self-correct?
Let’s say my guesstimate, for any field chosen at random, is that a consensus takes 80 years to be corrected, if indeed it needs correcting.
Can you disprove this guestimate empirically?
As I said, I’m not the expert, and apparently neither are you, based on many of the posts I’ve seen here. Arm-chair McExperts may believe what they want, but they don’t necessarily follow the data to the facts.
The only way the denialists’ claims can work is to assume anything that does not agree with their beliefs must be part of some conspiracy.
Facts don’t matter. Science doesn’t matter. The only thing that matters is a pre-conceived comfort level of what denialists want to believe is reality.
The denialists pattern is the same – rant and deny the facts, but present nothing in return. No alternate theory. No explanation why the data says what it says, other than claiming it’s part of a conspiracy. Any data that contradicts the denialists’ position must be faked. Such a convenient position to take.
I can see why denialists run to these blogs instead of publishing real scientific papers. They can’t prove their claims. So appealing to the ignorant masses is their only outlet. No debates are wanted. When threatened with real data, denialists resort to name-calling.
If climate science is so wrong about ACC, then by extension, denialists claim that ALL science is wrong. A bit of a leap, even for ignorant denialists. Denialists claims imply that all scientists and their data must be suspect, because they work within a closed network of conspirators, always looking for a way to game the system. If that’s how it works, it’s worked pretty well for you all up to this point. After all, even denialists enjoy the fruits of scientific progress. Or is it by sheer random chance that all the technological advances were made in spite of all the faked data?
There are parallels here. The so-called ufologists also believe there’s a conspiracy to hide crashed alien ships. I guess that puts denialists in the same league as wing-nut conspiracy theorists.
If ignorance is bliss, denialists must be ecstatic.
Based on the educated responses to my posts, I can see I’ve stepped into the inter-sanctum of the denialists place of worship.
It’s time for your prayers. Go ahead and bow at the altar of ignorance.
I’ll leave the inner sanctum to the worshipers of ignorance.
http://www.foodconsumer.org/newsite/Non-food/Healthcare/harvard_says_swine_flu_was_oversold_0201100713.html
A note on how PP can make a stampeding idiocy out of society.
Skeptical Skeptic (06:53:20) :
Nice diatribe!
“Arm-chair McExperts may believe what they want, but they don’t necessarily follow the data to the facts.”
Huh? If anything, you should most assuredly follow the facts to the data, if by data in this sentence you mean a conclusion of some sort. If not, then I do not know what you are trying to say.
“If climate science is so wrong about ACC, then by extension, denialists claim that ALL science is wrong.”
If that is what you choose to believe, McSkeptic, then so be it. Fact is, there are plenty of pieces missing from the AGW case. Maybe they flew away in UFOs? I think gravity will still hold when the world finds out that natural variation has been masking the so-called climate signal for years now. But, maybe in the vein of this post, I should bolt a pair of shoes to the floor? You know, just in case?
Dear Skeptical Skeptic,
A quote from Albert Einstein:
No amount of experimentation can ever prove me right; a single experiment can prove me wrong.
That is how science is.
So, something big and obvious like the medieval warm period, simply blows the whole CO2 global warming thing away.
Furthermore,
SS,
You said
The denialists pattern is the same – rant and deny the facts, but present nothing in return. No alternate theory. No explanation why the data says what it says,
I think the problem is that your global warming gods won’t show their raw data… oops they lost it!
Show me the data and how you measured it and I will show you the truth.
Skeptical Skeptic is assuming that Co2 must drive the climate because there is no other theory in place to explain. This does not make Co2 driven climate correct by default. He also uses the” no peer-review” argument even though it has clearly been shown to be corrupt. You say you are no expert, and I would have to agree. Posting links to sites that “prove” global warming is as “arm chair” as it gets. I have lived off grid, have you? I have spent more time out doors (especially in winter in Canada) than anyone I have ever met. Come winter camping with me and we will see how much you miss the comforts you currently take for granted. This is the reason for my previous questions posed to you. Have you thought your line of thinking through to it’s conclusion? What kind of world do you want? Gilligan’s Island? Flintstones? I love spending time out doors, but it sure makes me appreciate being able to come back inside and warm up now and then. I appreciate that my life expectancy is ~65 years rather than 35. You are probably a young lad (I am 46) and I pride myself on my eco-friendliness ( mainly because I abhor wastefulness) and try to make my world as sustainable as possible. I am saddened by the wastefulness of our society and that is where money should be focused and spent. Not to reduce a wonderful life giving gas known as Co2. Tell me why greenhouses keep there PPM level at 1000? And tell me what kind of world it is that you want?
“Skeptical Skeptic (06:53:20) :
If climate science is so wrong about ACC, then by extension, denialists claim that ALL science is wrong.”
You should really learn about logic. I mean, not social sciences logic. Boolean logic for a start would do.
“Skeptical Skeptic (06:53:20) :
If climate science is so wrong about ACC, then by extension, denialists claim that ALL science is wrong.”
Oh sorry! I misunderstood you! The sentence only wants to SOUND like logic because it is simply what you want to sell, in other words, dialectic materialsm, diamat, Hegelian dialectic. Now that’s not so bad. Surely suffices to get a green following. Or convince some journos to reprint and believe it. I see your point now.
Skeptical Skeptic (18:05:09):
Thanks for the input. However, your most recent post (Skeptical Skeptic (06:53:20) 🙂 suggests you are more a troll than a person interested in engaging in sensible discussion of the science surrounding AGW.
If you’ve spent any time reading this blog and have any degree of thoughtfulness, you could not rant as you have. Most folks here are serious and all the articles Anthony uses to start discussions are serious (even if some are humorous). Are the articles right or are they wrong? Is the case for/ against AGW strong or weak? That’s what we’re here to discuss.
For me, this site offers a reasonable and reasoned approach to challenging AGW orthodoxy (if I may call it that). I have not found a site that provides a similar approach to reviewing the case in support of AGW. I would like to find one — which is why I asked you the initial question I did. Your “you have to educate yourself” riposte has a taunting tone that belies your apparent effort to answer my question constructively.
As RACookPE1978 (20:05:38) : points out, many of the sites you offer (although my comment here may not be true of all , I will see for myself) are hardly authoritative or unbiased — even those that claim they come from a scientific perspective (e.g., National Geographic, New Scientist).
I am not an expert in climate science. I am a reasonably well-educated (PhD in a quantitative social science) and feel competent to evaluate scientific work along with the views of others more knowledgeable than me who in turn evaluate and opine on scientific work. I ignore rants as well as those whose opinons on climate science seem more informed by their views of appropriate government policy than by the science itself.
For me, you fall into the latter category. I will consider your input, but could do without the rant.
Re: Skeptical Skeptic (January 2, 2010 06:53:20):
“The only way the denialists’ claims can work is to assume anything that does not agree with their beliefs must be part of some conspiracy.”
No, the ClimateGate evidence suggests self-interested group-think about the fundamental data and its interpretation.
“The denialists pattern is the same – rant and deny the facts, but present nothing in return. No alternate theory.”
1) Natural climate variation (PDO, AMO, etc.) to account for response lags
2) Cosmic Ray effects on albedo (Svensmark). Better Phanerozoic correlation than CO2 (Shaviv)
3) IRIS effect (Lindzen)
4) Land use changes including UHI
6) Wrong sign on IPCC feedback parameters (Spencer, Lindzen)
5) More
6) All of the above
“If climate science is so wrong about ACC, then by extension, denialists claim that ALL science is wrong.”
Bad logic. Compare consistent use of “denialists” to argumentum ad hominem (Attack on the Person), a classical fallacy. Compare “then by extension” to yet another classical fallacy, Affirming the Consequent.