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Congress manufactures doubt and denial in climate change hearing

Posted on 21 May 2015 by dana1981

US Congress periodically holds hearings on issues related to climate change. Because the subject has become a partisan one in America, they generally follow a predictable pattern – Democrats invite science and policy expert witnesses who agree with the expert consensus on human-caused global warming and the need to address it, and Republicans invite witnesses who disagree.

John Christy at the University of Alabama at Huntsville is one of the fewer than 3% of climate scientists who publishes research suggesting that humans aren’t the primary cause of the current global warming. He’s thus become one of Republicans’ favorite expert witnesses.

Last week, the Committee on Natural Resources held a hearing to discuss draft guidance by the the President’s Council on Environmental Quality to include carbon pollution and the effects of climate change in the consideration of environmental impacts of federal projects, as part of the National Environmental Policy Act (NEPA) review process. Needless to say, the Republicans on the committee don’t like the idea, as is clear from the hearing highlights and lowlights in the video below.

 Highlights and lowlights from the May 13, 2015 Committee on Natural Resources NEPA hearing.

Christy Manufactures Doubt on Model Accuracy

Given that the hearing was ostensibly about environmental policy, most of the witnesses were policy experts. John Christy was the lone climate scientist invited to testify. His testimony focused on manufacturing doubt about the accuracy of climate models, climate change impacts, and about individual American projects’ contributions to global warming. On the accuracy of climate models, Christy played rather fast and loose with the facts, saying in his written testimony (emphasis added),

Do we understand how greenhouse gases affect the climate, i.e. the link between emissions and climate effects? A very basic metric for climate studies is the temperature of the bulk atmospheric layer known as the troposphere, roughlyfrom the surface to 50,000 ft altitude. This is the layer that, according to models, should warm significantly as CO2 increases ... 

I was able to access 102 CMIP-5 rcp4.5 (representative concentration pathways) climate model simulations of the atmospheric temperatures for the tropospheric layer and generate bulk temperatures from the models for an apples-to-apples comparison with the observations from satellites and balloons ... On average the models warm the global atmosphere at a rate three times that of the real world ... As such, they would be of highly questionable value in determining policy that should depend on a very confident understanding of how the climate system works. 

Christy’s oral testimony referred only to the temperatures of the “atmosphere” and “planet.” As shown in the above quote, in his written testimony, Christy twice referenced the troposphere – the lowest layer of the atmosphere from the surface to 50,000 feet (15km) in altitude. However, to argue that climate models have been inaccurate, Christy showed a graph of only mid-troposphere temperatures. The mid-troposphere is the atmospheric layer from about 25,000–50,000 feet, or about 8–15km in altitude. 

One might reasonably ask why Christy only showed data for such high altitudes. For perspective, the highest point on the Earth’s surface is on Mount Everest at 29,000 feet (8.8km), and the highest elevation city in the world is La Rinconada, Peru at 16,700 feet (5.1km). Humans live in the lower troposphere, not the mid-troposphere.

As weather balloon data show, the mid-troposphere is warming significantly more slowly than the lower troposphere, where the increasing greenhouse effect has more of an impact on temperature changes. It’s possible that climate models aren’t quite getting the vertical profile of atmospheric temperature changes quite right. It’s also possible that the measurements themselves aren’t accurate – different scientific groups have significantly different estimates of the rates of warming in the low and mid-troposphere. Some combination of both is undoubtedly true.

However, climate models have done a good job matching the observed temperature change at the surface and in the lower troposphere, where humans live. We understand the workings of the Earth’s climate much better than Christy suggests, especially where it matters most to humans. This is a key focus of my book and one of my Denial101x course lectures.

 Model success stories Week 4 Deial101x lecture by Dana Nuccitelli.

For further detail on how climate models are built, see this Denial101x interview with expert climate modelers. Toward the end of the video, Professor Andrew Pitman provides this quote that John Christy and Republicans in Congress would do well to learn from.

pitman quote

Professor Andrew Pitman describing that models are just one line of evidence for climate change risks.

Christy Manufactures Doubt on Climate Impacts

Christy also suggested that Americans have not yet experienced increases in various extreme climate impacts such as heat waves. This is a particularly strange example, given that Christy doesn’t deny that temperatures have risen significantly, and an increase in heat waves is an obvious consequence of rising temperatures. There is indeed a large body of scientific literature showing that heatwaves and other types of extreme weather are becoming more frequent and intense due to human-caused global warming.

Christy also claimed that carbon emissions from any single federal project will have a negligible impact on climate change; an extremely flawed argument. If I dump a bucket of motor oil into a nearby river, it will have a negligible environmental impact. Should we then allow everyone to dump their used oil into rivers without regulation? It’s cumulative national and global carbon emissions that matter, and every source of emissions should be appropriately considered.

Consensus Denial

The expert consensus on human-caused global warming was discussed several times during the hearing. Rep. Louie Gohmert (R-TX) asked of Christy,

You ever feel like Galileo? You remember Galileo? The overwhelming amount of science was against Galileo, and the other side of this got money from the Church, they got money from the government from their research opposing Galileo, and yet Galileo was right.

This is of course incorrect – the scientific evidence was on Galileo’s side, although it’s correct to note that the climate science evidence is overwhelmingly against Christy. Christy himself has tried to have it both ways on consensus, previously having claimed to be part of the 97% (he’s not), and in the hearing claiming in response to a question about a NASA statement on the on the consensus,

I would hope I could disabuse you of that 97% number. That’s been debunked by several studies ... remember, the NASA website is controlled by a specific government.

This claim is false. Two poor responses to our 97% consensus paper were published in off-topic journals and were themselves debunked. This was also an ironic choice of words by Christy. As documented in The Hockey Stick and the Climate Wars, Christy previously wrote a letter of complaint to the president of Michael Mann’s university after Mann correctly noted in Senate testimony that the myth that Christy’s satellite data contradicted surface temperature data had been debunked. 

My colleagues and I have thick skins and won’t be writing to the president of Christy’s university, but he’s once again confused about just what has been debunked.

Why it all Matters

Rep John Fleming (R-VA) and Christy discussed that mass extinctions and mega-droughts have occurred naturally in the past – the ‘climate has changed before’ logical fallacy. To take comfort in the fact that climate change has led to mass extinctions and mega-droughts, while we’re in the midst of a rapid human-caused climate change, is utterly misguided. These are the sorts of dangerous consequences we’re trying to avoid triggering.

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Comments 1 to 33:

  1. President Obama made strong references to AGW in the graduation speach atthe Coast Guard Academy.  Los Angeles Times report.

    Hopefully the public will support action.

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  2. The article makes plenty of sense to me, so why do people like Christie go on making these misleading arguments? They are not reasoned scepticism, which we need, they are pretty dishonest.

    Perhaps he is an attention seeker, or has some grudge against the climate community, yet these people are in effect sabotaging the debate and putting the entire planet at risk. It's simply preposterous.

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  3. Think how important his position makes him. How many second rate scientistists get trotted out repeatedly to testify before Congress? If Christy were to accept the overwhelming body of scientific research, then he's just one tiny researcher in a sea of hard working scientists. As far as I can see, his contrarian position is the only thing that makes him important.

    Same works for people like Watts. He has to maintain his position regardless of evidence to the contrary, because that's all that makes him important. 

    What an awful position to be in. All the nickle and dime deniers will eventually disappear in their anonymity. People like Christy are writing themselves into history, and ultimately history is not going to look back kindly.

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  4. Rob,

    Though "making them important (and the money that allows them to gather to support their activity)" may be part of their motivation, I believe a more significant consideration is that they, like too many others, do not care what 'history' or 'legacy' they leave.

    They are almost certainly doing what they are doing out of self-interest. They probably do not even care if during their lifetime their deliberate actions get exposed as unacceptable behaviour there was no doubt they knew was unacceptable. And they are very unlikely to care what people think after they are done with their time in this existence.

    The success of people with that type of attitude is a seious problem, and always has been. It is very difficult, but not impossible, to change the attitude and mind of someone who has chosen that course of action in their life. The continued efforts to improve the understanding of what is going on is ultimately the best way to win over those type of people.

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  5. Next year is a Presidential election year in the US, and the election of a Republican President would open many doors for scientists who have conservative leanings.

    There are also high-profile jobs as science advisers and officials in the Administration. 

    Positioning oneself as a working scientist who can speak authoritatively on matters improtant to the political bosses would be no drawback to your career. Of course, that is exactly what deniers accuse the majority of climate scientists of doing.

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  6. It would be good if the Democrats and Republicans had to select three new expert witnesses each time. After a short while, the Republicans would run out of experts to ask.

    Here in the UK, there are so few potential sceptic expert witnesses that when in January 2014, the House of Commons select committee on energy and climate change met to discuss the IPCC Fifth Assessment Report in a similar format, the sceptic side had to jet in two of its witnesses, Richard Lindzen and Donna Laframboise from the US and Canada respectively. The other witness was Nic Lewis.

    So in the UK at least, I'd say that the 97% figure for the consensus is, if anything, a low end estimate. I'm struggling to think of a single UK-based climate scientist who disputes the basis consensus. Even Nic Lewis's estimates for climate sensitivity are within the range of the IPCC's, albeit at the lower end.

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  7. Some of these people are frankly sociopathic.  They are so focussed on their agenda that rational thought and considering alternatives is completely foreign.  I've worked with several people like this and every time I've just given up arguing with them - it's not worth the angst because they KNOW they are right, and nothing that I or anyone else can do will change that because they ARE right.  Yeah right!

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  8. Climate hawks need to either find a way to make progress on this issue dispite the politics, or find a way to alter the politics. Otherwise progress is going to continue to be blocked by the politics.

    Nothing is certain, but history gives us a strong prediction that the next president will be an "R" type.

    Looking back over the past 150 years, there were only two instances when two Dems were elected consecutively. Truman followed FDR, but Truman was able to run as an incumbent due to FDR dying in office. Johnson followed JFK but again he ran as an incumbent for the same reason.

    Otherwise, the history of presidents alternates R-D-R-D-R-D. George HW Bush broke the pattern for the Repubs when he followed Reagan. Gore nearly broke the pattern, even won the popular vote, but W still became the next president.

    So, if 150 years of history continues to guide the future, then we will need to figure out how to make climate progress with an R-type president after 2016.

    The other alternative is get enough people involved in climate action to break the long established pattern.

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  9. Consumer Power: the Governator called it when he said Governments don't lead i.e. DIVESTMENT!!

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  10. @7, Politics is tribal: did you miss the youtube video where Mike Tyson is telling 50 cent not to go into boxing as a promoter because he had no idea how tribal it was and that the red and blue corner represented Democrats versus Republicans and it went back to when the Irish street gangs fought ,... I dunno,... yadda yadda ... and that instead of everyone getting hurt it was your man against theirs sort of thing but, yeh, it was pretty funny!??!

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  11. @2, It's just pause-button politics. The captains of todays industry know the paradigm is changing but to what exactly: details matter don't they? They all need to retool and get back to enjoying their superior market share positions that they enjoy today so it really is quite understandable.

    Stagnation is close to death so that ensures change happens when two political forces oppose each other.

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  12. ... think about it this way: who says all these seeming fraudulent skeptics aren't just playing games to force the real science to get on with the job of providing certainty in the market place?

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    Moderator Response:

    [DB] Font format shifted from all-bold to normal.

  13. Bozzza @ 12. You argue the fraudulent sceptics force everyone to produce rigorous science. This is like arguing that computer hackers serve a good purpose, or that bank robbers serve a good purpose by forcing banks to have better security, so its not a great argument. Lying or being misleading just doesn't seem justified to me. What if both sides played the same silly game? As far as I can tell the IPCC are very upfront and play by the rules.

    Sometimes I wonder if some of these sceptical characters are just sociopaths. Can you really argue such people serve a good purpose?

    There is also is a big difference between sceptical characters like Lindzen who have some reasonable contribution and characters like Christopher Moncton who are pretty much dishonest, in my opinion. But it is loudmouths like Moncton who sometimes have an effect on politicians, sadly to say.

    The main issue is science is complex and very intricate and a easy target for cheap or misleading scepticism. We cant allow the sceptics to get away with that. When politicians pay too much attention to the sceptics they are often listening to misleading fanatics with all sorts of weird agendas or personality issues. These people can't make it in the mainstream,  so set up shop as resentful, opinionated people happy to be completely dishonest.

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  14. Computer Hackers are the perfect analogy because it  has long been argued they wear different coloured hats... I'm just doing an Ed De Bono and allowing myself to be wrong: sure it's immoral to lie but greed justifies many things and on that count I don't think it's stretching the bow all that far to suggest it as completely probable.

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  15. As for sociopaths: I can't really argue towards their usefulness(who would want to) yet they do say the genius of the human species is in accepting the mentaly ill within society as(going back to de bonos lateral thinking definition of allowing yourself to be wrong) they still provide ideas of which we can all learn from. If the imagined elite and the proles make up 10% then the masses make up 90% and it is a spark from the masses on which we all depend, generally speaking.

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  16. @7 &15.   I believe that the people to whom you are referring actually better fit the checklist criteria for psychopathy - often compared to the DSM IV diagnostic criteria for Antisocial Personality Disorder, but many practitioners distinguish psychopathy separately. But, since we're into labels, despite his past and his credentials, I prefer to call Christy a "scientist" or simply a denier, as a truly skeptical scientist would not be uttering such antiscientific nonsense. 

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  17. I would like to know how much one of these congressional committee hearings cost the U.S. taxpayer considering all costs,i.e., salaries of congressmen, senators, and their staffs, witnesses salaries and expenses and the expenses for everyone and everything associated with these hearings. House republicans have voted to kill "Obamacare" over 60 times. Cost? Astronomical!  These hearings that pay deniers to lie must stop. There are penalties for lying to congress and they should be inforced. The U.S. taxpayers have got to stop sending these idiots to Washington who call these witnesses.

    BTW, the 97% of climate scientists who support anthropogenic global warming should be updated to 99.9%. One would be hard pressed to find 3% of climate scientists who do not support AGW. 0.1% maybe.

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  18. bozzza,

    People who think outside of the norms of a society, people who see things from a novel perspective, are indeed the sparks of ingenuity. However, the people mentioned in the article, the likes of Christy and the ones who invite him to speak, are almost certain to be aware of the deliberate deceptions they create and disseminate.

    These are not "outsiders" unaware of what the mainstream is aware of or thinking about explanations for all the observations/information available from a different perspective. These are people who are fully aware of vast amounts of information who deliberate focus on bits of information and deliberately try to create claims that will sound convincing to someone who is willing to be easily impressed, someone inclined to want to hear and believe the fantastical unbelievable tall tales they tell.

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  19. Of course, yet what I am saying is business being business means shennanigans must played in order to secure the advantage of meaningful fact....I am referring to the rich maintaining their share and if they are entrepreneural it is shades of grey as to whether they deserve respect or not because let us face facts: market forces- however diluted by government interference- are charged with supplying goods and services to the largest of degrees....!!

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  20. Bozza,

    My MBA and life experience has helped me understand that what many refer to as 'market-forces' are just artificial motivations of human attitudes and actions based on a set of artificial rules put in place by humans. And the current rules have been significantly developed through the influence of people who knowingly will pursue unacceptable ways of personally benefiting as much as they are able to get away with.

    References to 'government interference' come from a perspective of someone inclined to believe that all people free to do as they please will naturally produce a lasting constantly improving better future for all. The actual facts of the matter clearly contradict that belief. Potential profitability and popularity of actions that can be understood to be unacceptable leads many people to fight for 'freedom from any and all restrictions'. And those pushing for such freedom are also very likely to be the ones wanting more rules and enforcement, but only selectively applied and focused on the things they do not personally like others to have the freedom to do. Their main purpose for such actions and policy is to protect their opportunity to get away with unacceptable pursuits of personal benefit because they are 'deemed to not be illegal or their actions are selectively not monitored and penalized'. They will even use their influence to promote the waging of war (in other nations), to 'protect their personal interests and deaires'.

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  21. Bozzza, you appear to be basically using your dislike of government input into markets as some weak excuse to try to justify people opposed to this stooping to dishonesty. You constantly make excuses for dishonesty or other unethical behaviour. I doubt that you are really playing devils advocate, and your argument doesn't even pass first base. 

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  22. I accept the argument is not strong. I read OPOFs comments(just seconds ago infact,... well minutes because I did ponder it to make sure i understood it and not fly off on a tangent like I can do as it was written well enough to show he knows a few things) and conclude that business certainly can be a very dark world. I wasn't disputing that but perhaps I should digress from sticking up for its shennanigans.. yes I understand you are saying these are not simply business shennanigans we are talking about but rather complete deception for no purpose.


    I'm a greens/labor voter but I still try and justify how the world we all do of course.

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  23. Also, no: I do not dislike government intervention- I understand better than most that Government helps farmers to even grow a marketable product let alone provide standards that stop people dying in the workplace in all manner ways: I'm not a dumb lib... simply just trying to put forward a fair view of the world worthy of discussion rather than circular back-patting!

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  24. Judith Curry who seems to be quite level-headed raises an interesting question about the Congress hearings and Presient Obama's speech.  She questions what the anticipated reduction in temperature will be against the climate models assessments as a result of an 80% reduction in CO2 by 2050.  I am struggling to find information on this.  It is an important issue given the costs involved of an 80% reduction.  Can someone help, please?

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    Moderator Response:

    [JH] Suggest that you pose your question directly to Judith Curry on her website.   

  25. Cowpuncher, the IPCC WG1 show results for different carbon pathways (RCPs). I see you worried about reduction costs but have you also looked at future costs if you dont? I am reasonably amazed at your "level headed" assessment of JC given these statements and her (non) standing in the research community. How did you make that assessment?

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  26. In his testimony, Christy says that sea levels have risen for the last 20,000 years (OK) but the says that sea levels will continue to rise in the future.  

    I don't understand what he is trying to say  and am wondering if someone did.  

    If man is not overpoweriing the natural Milinkovitch cycles (as he claims), why would he think sea levels will continue to rise?  They will be rising, of course, due to Man's effects, and without man's effects they would be going down, right? 

    Is Christy simply trying to avoid the use of sea level directional change as a proof of Man's effect?  If so why might sea levels possibly rise due to natural causes.  Don't understand where he is going with that one.

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  27. Cowpuncher @24, Judith Curry's question is not so much interesting, as poorly framed.  Specifically, it tacitly assumes that there are not costs from AGW after 2050.  As it happens, because of the slow response rate to forcing, a reduction in emissions now will not appreciably effect temperatures until about 10 years later.  Further, because we must decrease emissions gradually, an 80% reduction will not be fully implimented (if it is) until 2050.  Consequently most of the temperature effect of such a reduction will occur after 2050.

    As it happens, RCP2.6 shows an approximate 80% reduction in CO2 emissions by 2050:

    We can therefore use its temperature predictions to look at the claim:

    At 2050 it only amoutns to 0.75 C between RCP2.6 and RCP8.5 (no mitigation).  By 2100 that difference increases to 3.2 C, and by 2200 to 6 C.  With costs increasing more than linearly with increased temperature, Curry is attempting to exclude more than 90% of the cost differential from the equation.  Indeed, with RCP8.5 tempertures rising to levels where parts of the tropics may be seasonally uninhabitable by 2050, ignoring long term costs amounts to tackling climate change by putting your head in the sand.

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  28. @ 26, the answer is because we are coming out of an ice-age!

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  29. scaddenp - there is far too much personal denigration and ad hominem attacking in the wider AGW debate fro me to add to it.  Curry is a highly accomplished scientist with a wealth of published material and she seems to via away from any extreme positions.  I am also sure she will be wrong on some issues but she is making a contribution to the search for a fuller understanding of climate.

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  30. Cowpuncher: how about doing some reading so you can bring something to the table?!!?

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  31. What Curry actually publishes in the scientific realm may be of value but her misinformation in the public arena is not. What information sources are you trusting in your evaluation of what is an "extreme position". Do you regard the IPCC position (the scientific consensus) of ECS in range 1.5 to 4.5 extreme?

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  32. @26 and 28

    Bozzza,  Perhaps  I was not clear enough.  We know why sea levels have risen since 20,000 years ago  - it is due to a transition from a glacial to an interglacial period.

    My question is why Christy would claim that sea level would continue to rise today and into the future due to natural causes.  We are now well out of an interglacial period and, I thought, in a stable interglacial period with no or very little change in sea levels.  If any natural change would be in the works for the future I thought sea levels might actually be decreasing somewhat in the immediate future as we begin to head back towards the next glacial period.

    So I still don't understand why Christy would claim that sea levels will be rising due to natural causes in the future.  The only explanation I can think of is that Christy suspects that sea levels will indeed rise due to Man's effect on the GHGs and, therefore, is claiming natural forces will do the same - but has no good reason to make that claim.Thus, if there is such a reason for Christy's claim, perhaps someone could point out what that is.  Otherwise, it would appear that he is misinforming the members of this congressional hearing. 

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  33. Actually, Cowpuncher, what Curry is doing--trying to turn uncertainty into a commodity--is feeding political action that seeks to end government-funded climate science.  It's not really shooting herself in the foot, since she'll have plenty of private funding sources when she takes her early retirement.

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