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Christy's Unconvincing Congressional Testimony

Posted on 10 March 2011 by dana1981

On 08 March 2011, the U.S. House Energy and Commerce Subcommittee on Energy and Power held a hearing entitled entitled “Climate Science and EPA’s Greenhouse Gas Regulations.”  As the US Environmental Protection Agency (EPA) has begun regulating greenhouse gas emissions from large sources, Congressional Republicans are seeking justification to revoke their authority to do so through the Energy Tax Prevention Act (H.R. 910).  This hearing was held to allow scientists from both "sides" to present their case as to whether our understanding of climate science justifies the EPA's greenhouse gas regulations. 

One of the top witnesses called by the Republicans was Dr. John Christy.  His full written testimony can be viewed here.   Most of the quotes below come directly from that written testimony.  As we'll see below, Christy's case for continuing on our current path and revoking the EPA's greenhouse gas regulation authority is primarily based on a repetition of a number of long-debunked myths.

Extreme Weather

Christy began his written testimony by discussing various recent extreme weather events, and arguing that they cannot be attributed to human greenhouse gas emissions.

As Francis Zwiers noted in his testimony for this hearing, while individual extreme weather events cannot be blamed on global warming, "two new papers in Nature (Min et al. 2011, Pall et al. 2011) have presented evidence that changes in the intensity of extreme precipitation since the middle of the 20th century may be linked to human induced global warming, and that in at least one instance, that human influence on climate had likely substantially increased the risk of flooding."  Other recent research has detected a human influence in observations of extreme temperatures (e.g., Christidis et al., 2005, 2010; Zwiers et al., 2011). 

Temperature Trend

"In 1994, Nature magazine published a study of mine in which we estimated the underlying rate at which the world was warming by removing the impacts of volcanoes and El Niños (Christy and McNider 1994.)...The result of that study indicated the underlying trend for 1979-1993 was +0.09°C/decade...I have repeated that study for this testimony with data which now cover 32 years...In an interesting result, the new underlying trend remains a modest +0.09 C/decade for the global tropospheric temperature"

Christy's method of filtering out the El Niño influence – by removing the tropical sea surface temperature (SST) trend – seems like a rather blunt and imprecise way to remove the El Niño Southern Oscillation (ENSO) signal.  After all, the tropical sea surface temperatures could have an upward trend for other reasons (for example, due to an increased greenhouse effect!).  Christy's assumption that the tropical SST trend could only be due to ENSO seems unjustified.

In 2008, David Thompson attempted to extract the ENSO signal from the HadCRUT3v data using a different methodology, and Gavin Schmidt applied the same approach to the GISTEMP data.  They found that removing the ENSO signal from the surface temperature data did not change the global warming trend over the past 30 years.

Similarly, Tamino recently removed the estimated impact of El Niño, volcanic eruptions, solar variation, and the residual annual cycle from various global temperature data sets (Figure 1).

tamino trend ENSO volcanic removed

Figure 1: Adjusted annual average temperature data with the estimated impact of El Niño, volcanic eruptions, solar variation, and the residual annual cycle removed (Source: Open Mind)

The resulting average warming trend is approximately 0.17°C per decade; embarrassingly enough, even Christy's own UAH data show 0.16°C per decade, far larger than 0.09°C per decade trend of his testimony.

Moreover, as the name suggests, ENSO is an oscillation.  It alternates between positive and negative states, and thus does not cause long-term warming trends.  ENSO also does not create or retain heat; it just moves heat from oceans to air and vice-versa.  Thus, even if it caused a surface air warming trend (like 35% of the warming over the past 32 years, as Christy argues), the oceans would cool correspondingly, which they are not.  Thus it appears that Christy's reduced warming trend is a result of his imprecise method of attempting to remove the ENSO influence.

Should Have Seen More Warming?

"+0.09 C/decade for the global tropospheric still only one third of the average rate the climate models project for the current era (+0.26°C/decade.)"

As we've previously examined, the Earth's surface temperature is warming almost exactly as much as climate models expect.   However, it's true that climate models also expect the lower troposphere to warm slightly faster than the surface, and that according to UAH, it is not.  That being said, the discrepancy may very well be due to difficulties in analyzing the raw satellite data, which is fraught with problems like orbital decay of the satellites, and the challenge in isolating each different layer of the atmosphere.

UAH does not have the only approach to analyzing the satellite data.  For example, Fu et al. (2004) apply a slightly different correction to attempt to isolate the lower troposphere temperatures, and conclude: 

“The resulting trend of reconstructed tropospheric temperatures from satellite data is physically consistent with the observed surface temperature trend. For the tropics, the tropospheric warming is ~1.6 times the surface warming, as expected for a moist adiabatic lapse rate.”

Vinnikov & Grody (2006) have suggested that the method used by the UAH group was insufficient to compensate for the impact of the diurnal cycle on the observations.  Like Fu et al., their work concludes that the troposphere is warming faster than the surface, as climate models expect. 

"The observations at the surface and in the troposphere are consistent with climate model simulations...The resulting global averaged tropospheric trend is +0.20 K/10 yr"

In fact, as tamino noted,

"All the [satellite lower troposphere temperature] analyses except UAH are compatible with computer model projections of tropospheric warming; the error ranges include the values expected from model simulations."

Perhaps Christy should consider the possibility that the problem is not that the troposphere isn't warming as much as climate models expect, but rather that his analysis is (still) underestimating the troposphere warming rate.  After all, UAH does not have a stellar track record when it comes to accurate data analysis.

Heating from Land Use Changes

"warming is dominated by increases in nighttime temperatures, with little change in daytime temperatures. This pattern of warming is a classic signature of surface development (land cover and land use change) by human activities."

Actually, greater warming during the night than day is a key signature of an increased greenhouse effect

Christy's argument here is not very different from blaming instrumental global warming measurements on the urban heat island (UHI) effect.  However, scientific organizations make great efforts to remove these types of local influences, and according to Menne (2010), are very successful in doing so.  That's why rural stations show the same warming trend as urban stations, well-sited temperature stations the same as poorly-sited stations, and satellites the same as surface stations.  The evidence is clear, and the warming trend is very real.

Hot Spot

"one of the clearest signatures or fingerprints of greenhouse gas warming as depicted in climate models...consists of a region of the tropical upper atmosphere which in models is shown to warm at least twice as fast as the surface rate of warming...We, and others, have tested this specific signature, i.e. this hypothesis, against several observational datasets and conclude that this pervasive result from climate models has not been detected in the real atmosphere."

As we have previously discussed several times, and as Christy should very well know, the tropical troposphere hot spot is not an anthropogenic signature.  Rather, it is the expected result of any global surface warming, and indeed there is evidence that the hot spot exists.

If Christy wants to argue that the hot spot is an anthropogenic fingerprint, he'll have to explain why the adiabatic lapse rate only applies to warming caused by greenhouse gases, and why climate models predict a hot spot from warming caused by solar and other natural forcings as well.  Frankly it's very disappointing that any climate scientist would argue that the 'hot spot' is an anthropogenic signal.

Climate Sensitivity

"Spencer tracks large global temperature changes over periods of several weeks...he finds the real climate system is dominated by negative feedbacks (probably related to cloud variations) that work against changes in temperature once that temperature change has occurred."

We cannot evaluate the equlibrium climate sensitivity to a large energy change over periods of decades to centuries by looking at global temperature changes over periods as short as weeks.  This approach is fundamentally flawed, and Spencer's results go against the many different lines of evidence using both empirical observational data and climate models which are consistent with the IPCC's range of climate sensitivity values

Additionally, several recent studies have examined the cloud feedback which Spencer argues is negative, but based on observations over much longer timeframes both in the tropical Pacific region (Lauer et al. 2010, Clement et al. 2009) and globally (Dessler 2010).  These studies all conclude that the cloud feedback is likely positive.

If Christy wants us to believe the many lines of evidence supporting the IPCC's climate sensitivity range are wrong, he'll have to do better than looking at temperature changes over inappropriately brief timeframes while ignoring the many other studies using larger amounts of data which contradict Spencer's results.


"the IPCC and other similar Assessments do not represent for me a consensus of much more than the consensus of those who already agree with a particular consensus."

The scientific consensus on man-made global warming is very well documented, and 113 countries signed onto the IPCC report.  Christy needs to just accept that very few climate scientists agree with his position.

Impact of Carbon Regulations

"we calculate that the impact of legislative actions being considered on the global temperature is essentially imperceptible....downward adjustments to North American coal use will have virtually no effect on global CO2 emissions"

Christy is essentially promoting the Tragedy of the Commons here.  If just the USA reduces its carbon emissions, it won't significantly reduce global emissions.  And if every country makes the same argument, nobody reduces emissions.  This is the purpose of international conferences and treaties - to get all nations to agree on reducing emissions.  And as the largest historical carbon emitter, the USA is a lynchpin in international negotiations.

More Carbon is Better?

"...the many positive benefits of higher concentrations of CO2 in the atmosphere, especially for the biological world"

As I recently discussed, we are currently on a path to trigger the Earth's sixth mass extinction event, with climate change playing a significant role.  The current rate of species extinctions far exceeds the natural background rate.  And as shown by the Penn State interactive application, production of many key agricultural crops will decline in a warming world, particularly at low latitudes.  Positive benefits of higher CO2 concentrations for the biological world?  Hardly.

Christy's Case

In attempting to argue that climate change is not dangerous and EPA regulation of carbon emissions is unnecessary, Christy has mainly relied on repeating several long-debunked myths:

Christy also tried to argue that we can't blame recent extreme weather on climate change, even though there is evidence for a human signature in recent extreme weather increased frequency, and what we're concerned about is future climate change.  He tried to attribute a significant amount of the recent warming to ENSO, even though ENSO physically cannot cause a long-term global warming trend, and thus incorrectly claimed we should have seen more warming.  And he tried to argue that climate sensitivity is low, based on data over a timeframe of just weeks.

Christy's disappointing testimony is a litany of already disproven assertions.  "Skeptics" will have to do much better to justify continuing on our current extremely high risk business-as-usual climate path.  The EPA's mandate to regulate greenhouse gas emissions is based on the conclusion that those emissions pose a threat to public health.  Christy's testimony only served to facilitate the Congressional Republicans' ideologically driven efforts to revoke the EPA's authority to contribute towards the protection of our future.  By his testimony, Christy did no service to his country.

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Comments 1 to 50 out of 54:

  1. I watched the hearing and was very disappointed with the proceedings. It seemed the policy makers (both sides) were more interested in making their own statements than trying to solicit and understand any of the science. It also seemed that both sides directed questions to get the answers they wanted to hear.
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  2. Dana,

    Didn't Christy also make the misleading comment that the Antarctic is gaining ice? I can't remember is he said that or that the Antarctic sea-ice is increasing. Either way, both are wrong and/or misleading.


    Yes, it was quite partisan and the Republican's especially seemed to intent on using their 5 minutes to make ideological rants or spout as many myths about climate science and AGW as they could. They should be ashamed, yet bizarrely they wear their ignorance like a badge of honour and (wrongly) perceive themselves as Galileos. Incredibly disappointing and discouraging that a nation who put men on the moon and which has made so many fine scientific discoveries has now sunk to this.

    What is annoying is that the EPA have addressed all their concerns in detail, see here.
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  3. Alby - I didn't see the live proceedings, but heard that Christy said something about Antarctic sea ice. Not in his written testimony though.
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  4. Dana,

    Sorry, you did say that you were addressing his written testimony.

    You should try and watch the proceedings, they will be available online soon I hope.
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  5. One of the things I have noticed about John Christy is: depending on who he is talking to, he will give entirely different answers about global warming. For example, in the bogus documentary "Dommsday Called Off", he says the Earth isn't even warming and the urban heat island effect accounts for most of the warming in surface temperatures. But, his UAH data agrees remarkably well with surface temperatures even though he says it doesn't, when interviewed by skeptical media outlets.

    Christy's self-contradictory claims are very perplexing given the fact that he has impressive credentials and is still actively engaged in climate change research.
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  6. Great run-down of the testimony.

    Keep up the good work.
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  7. That's an impressive turnaround time for such a detailed rebuttal!

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  8. John Christy, from his written testimony:

    "In the first aspect of temperature change, we have shown that the pattern of change at the surface does indeed show warming over land. However, in very detailed
    analyses of localized areas in the US and Africa we found that this warming is dominated by increases in nighttime temperatures, with little change in daytime temperatures. This pattern of warming is a classic signature of surface development (land cover and land use change) by human activities. The facts that (a) the daytime temperatures do not show significant warming in these studies and (b) the daytime temperature is much more representative of the deep atmospheric temperature where the warming due to the enhanced greenhouse effect should be evident, lead us to conclude that much of the surface temperature warming is related to surface development around the thermometer Subcommittee Energy and Power 14 John R. Christy, 8 March 2011 sites. This type of surface development interacts with complexities of the nighttime boundary layer which leads to warming not related to greenhouse warming (Christy et al. 2006, 2009, see also Walters et al. 2007, Pielke, Sr. 2008.)"

    (My emphasis)

    First, Christy claims that increased night time temperatures relative to day time temperatures is a "classic signature of surface development", which is itself false. Replacing grassland with concrete or tarmac (as at an air field, for example) will increase day time temperatures and decrease night time temperatures because of the reduced water content and hence heat capacity of the surface. It will also increase the difference because vegetation takes some of the incoming energy and stores it as chemical energy, which is then released over the full diurnal cycle.

    What is worse than that nonsense, however, is the claim that warming due to the green house effect will have a maximum effect in day time relative to night time (b). That is a straight forward falsehood. I doubt Christy can produce a single GCM result that supports that claim. On the contrary, simple analysis (as first done by Arrhenius in 1896, and confirmed by GCMs since shows that the effect of greenhouse gases is to reduce the diurnal cycle. IMO, this is not a mistake that could be made by anyone familiar with the literature on the green house effect.
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  9. From Christy's written testimony:

    "Secondly, regarding the recent Australian flooding as a physical event in the context climate history (with the estimated 2010 maximum river height added to the chart below) one sees a relative lull in flooding events after 1900. Only four events reached the moderate category in the past 110 years, while 14 such events were recorded in the 60 years before 1900. Indeed, the recent flood magnitude had been exceeded six times in the last 170 years, twice by almost double the level of flooding as observed in 2010."

    Christy supports these claims with a chart of flood heights of historical Brisbane River floods as measured at the Port Office, with the height of the 2011 flood marked in as a red bar. What he does not do is mention the effects of dams built on the Brisbane River and Stanley river (a tribuatary of the Brisbane) designed specifically to have a very large flood mitigation capacity. Is is very obvious why he does not. Modelling of the effects those dams would have had on historical floods has been carried out, and show that had those dams existed throughout the period of settlement, the 1893 flood would have peaked at 3.36 meters and the 1974 flood at 3.48 meters, compared to the 2011 flood's 4.46 meters. This is not evidence that helps make Christy's case, so unsurprisingly he makes no mention of it. But to not mention the potential impact of two major dams on the headwaters of the river when making such historical comparisons is at best negligence that calls Christy's ability as a scholar in to serious question, and at worst is a deliberate and transparent deception.

    Curiously, on the same day Christy made his testimony, SEQWater released its report on the 2011 flood. It shows modelling of the size of the 2011 flood as it would have been without dams. I have indicated the levels of the 1893 flood (no dams) and 1974 flood (Sommerset only) on the chart:

    (You will notice that although the 1893 flood would have been reduced below 2011 flood levels by the presence of both dams, it in fact had a greater volume of flow unimpeded. The difference is due to the different impacts of the dams based on differences in location, timing and patterns of rainfall. I did not have that information in my blog linked above, so some claims in it are in need of updating.)

    Christy goes on in his testimony to repeat slanders from The Australian, in particular that the flood was caused by negligence by the dam operators, and that 80% of the flood water came from a massive emergency release. On the chart above is modeled the flooding in Brisbane had there been no releases from the dam, and the flooding in Brisbane if only water released from the dam had been involved. At no point until well after the peak does the water from the dam exceed the levels of water from other tribuataries of the Brisbane. Clearly the Australian's claim, repeated uncritically by Christy is false.

    In fact the immediate cause of the flood was an Annual Exceedance Probablity 1 in 2000 year rainfall onto the immediate surrounds of Lake Wivenhoe, that rapidly drove the lake above safe levels. Of course, mentioning an AEP 1 in 2000 year event which was part of a larger AEP 1 in 100 to 1 in 200 year event, which followed just a fortnight after an (estimated) AEP 1 in 50 year event, which in turn followed by a mere 37 years an AEP 1 in 70 year event does not make a compelling case that wild weather is not on the increase.

    Far better to repeat glib falsehoods (apparently) then to actually analyze the data.

    (As a side note, Christy got his chart of Brisbane Flood levels from Roger Pielke Jr and hence had access to the information above about the effects of the dams before he made his report based on my comment 17.)
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  10. Tom Curtis at 22:33 PM, you make it all seem that the AEP is changing such that an area prone to flooding is being created where a city has long stood, rather than a city being created where a flood prone area always stood.
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  11. Actually, there is plenty of recent science that suggests intensity is increasing. I believe it is, but it would be hard to proove yet. The two recent papers regarding precipitation go a long way to prove it. A 1:2000 event locally is quite feasible in probability terms - an analysis of the data would be needed in depth.

    It is clear though that we are in for more of these swings in the weather. Perhaps we will be back to drought in a year or two and be wishing we still had all that water.

    The problem is that we just don't know which way the climate system will head for Australia. The models are based on our current understanding only. The additional moisture in the atmosphere will drive more intense/energetic storms, but whether they are over Australia or not is still unknown in my opinion.

    We are pushing the climate hard towards the unknown and we have to do something about it. Not listen to those who want to delay action!
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  12. PS. Great to see hard data on the Brisbane flood, thanks Tom.
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  13. Michael Tobis has some scathing comments from Ben Santer on Christy's testimony.
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  14. Ian #13 - thanks for the link.

    Very good point from Santer about the (mis)use of the debunked Douglass et al. paper. I got hung up on the (worse, IMO) mistake of calling the 'hot spot' anthropogenic, and glossed over that error.

    Just goes to show what a horrendous Gish Gallop Christy's testimony was. We couldn't even catch all the errors therein in this long rebuttal!
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  15. johnd @10, no! I make it seem, as it is, inappropriate, indeed dishonest, to compare flood levels from different periods without noting the effects of dams built on the river. If you want to defend that practice, please say so.

    I also rebut the casual repetition of false claims about the flood. Again, if you want to defend those false claims, speak up.

    Finally, I point out that the events of 2011 are extraordinary by any measure. But, if you had read my linked blog, you would have seen that those of 1893 were even more extraordinary by many measures. Wild weather and floods are a part of Brisbane's history. The only thing that is changing in that regard is that now mere thunderstorms are bringing floods comparable with those brought by cyclones in the past.

    All I can say is God help us when a cyclone next hits Brisbane in a La Nina year.
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  16. Tom Curtis at 11:27 AM, there is one dam that is being left out, and that is the city itself, and all the other infrastructure and changes that have occurred in the various water courses that artificially confines the natural flow paths.
    It is a common change that has happened on every water course where human occupation occurs.

    Geography has as much influence as the weather on all outcomes except for the timing of the events.
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  17. johnd @16, I find the suggestion that piers would dam the river more than mangroves (the natural river bank vegetation in Brisbane) interesting, but hardly credible.

    However, the suggestion that changes in geography between 1893 and 2011 rather than, say the 300 mm's (370 at Savages Crossing) rain in three hours dumped onto an already flooded river system are the major oontributor to Brisbane's flood is simply laughable.

    Below are the rainfall intensity graphs for Helidon (in the Lockyer Valley) and Lowood (just below the Wivenhoe dam wall) to give you some idea of the intensity of the rain involved. The primary flooding in Helidon is associated with the flash flooding in the Lockyer Valley on Monday 10th (google Grantham if you are unfamiliar with it); the peak at Lowood is associated with the second peak that fell mostly on the dam and surrounds. At the same time, Savage's Crossing (just east) received 370 mm in three hours.

    Note that the white dashed line on the graphs represents the expected intensity of a 1 in 2000 year event.

    The Helidon peak is associated with the first peak of inflows into Wivenhoe dam (dark blue line), the one at Lowood with the second peak. The dark red line indicates the peak flow at that location in 1974.

    Note, some areas of the catchment did not experience so intense rainfall, so that overall the intensity of the event over the period is about 1 in 200, but it is the peak falls over the Lockyer on the 10th that destroyed the Lockyer valley, and caused most of the flooding; and directly onto the dam and surrounds on the 11th, that necessitated the massive releases from the dam. And those events had probabilities of significantly less than 1 in 2000 per annum.
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  18. This was a win for the Republicans. All they need to show is controversy about the science and negative economic consequences of regulation.

    No one challenged Christy on his statements about day vs. night-time temperatures. No one pushed him to explain changes in outgoing and downward IR or stratospheric cooling.

    No one contested statements by Republican representatives or the skeptics about the negative impacts of regulation. They presented predictions of negative impacts from an increase in the price of energy. This is introductory level economics.

    People need to be reminded that economics is a model. We all now that model predictions should be validated against empirical data. We have some data now because of carbon emissions controls in the European Union and in part of the Northeast United States of America in the Regional Greenhouse Gas Initiative.

    These programs have not made those states into third world areas as Rep. Griffith assumes GHG regulation would do to the United States.
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  19. Notice also that other scientists were unwilling to go outside of their expertise but Christy didn't mind jumping right into economics.

    Trying to take the high road and stay within your expertise will win you no points in this sort of exercise.
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  20. Rovinpiper @18 & 19, I tend to agree with your political analysis, but disagree with your suggestion on tactics. Expert witnesses called in support of action on climate change should not step outside of their expertise while giving testimony. It is not their role to do so, and it is unethical for them to do so. Further, it would be tactically disadvantageous because when they make mistakes (as they inevitably will speaking outside of their area of expertise), the mistakes will be seized upon and trumpeted through out the blog-0-sphere as a means of discrediting their expertise even in those areas where they are in fact expert.

    Rather, the tactic that should be adopted is some actual skill in questioning by the Democrats and rational Republicans on the committee. If Christy makes comments about economics, he should be pointedly asked what his claim to expertise in economics is. Given his publication record, his expertise on climate science should be actively challenged by trolling through the example after example of egregious error. I'm sure suitable comments on using the wrong sign for how many years was it? could be judiciously used to make him look a buffoon.

    The deniers have been playing hard ball on this issue for years, and more rational politicians have been soft on the issue for fear of losing votes. Its about time they toughened up and started pointing out that the emperor of the deniers has no clothes.
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  21. It would seem that North America is exempt from weather extremes caused by AGW:

    Note, the above link is from NOAA

    And of course, we have the tropical storms.

    It would seem that the testimony given by the AGW proponent is slightly scewed.
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  22. Camburn can you please specifically address Christy's testimony, and if you think what Dana (and others) have noted, then please address those specific points. Quite frankly your posts thus far have been off topic and I'm surprised that they have not been deleted.

    FWIW, those interested in seeing for themselves the trends in extremes are doing for the USA, go here.
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  23. Albatross:
    I gave a link to world wide cyclones/hurricane strength, number etc.
    The link of extremes in the USA are all within climatic norms for our country.

    UAH and RSS are both well within error bars of each other. The idea that Dr. Christy is fiddling with the data is unsupported. When there was an error detected he was very open about it and corrected it.

    This post was about US testimony. I am trying to show why AGW is not a concern in the USA. In reality, we have not been affected for some reason.
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    Moderator Response: [DB] In reality, people who have taken the time to read and understand the science and the primary literature in the field disagree with you most severely.
  24. Camburn, please try to get on topic. We're talking about Christy's testimony, and whether GHGs pose a threat to public health would also be a relevant topic. Random criticisms of the EPA are not on topic.

    Nobody has proposed a carbon tax in the USA. EPA regulations are not a tax. A cap and trade system is not a tax. Also, nobody accused Christy of "fiddling with the data".
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  25. Dana,

    You have probably seen this message Dr. Santer has posted regarding Christy's misleading testimony:

    "I have had a quick look at John Christy's recent Congressional testimony. Many aspects of it are deeply troubling. From my own personal perspective, one of the most troubling aspects is that Christy cites a paper by David Douglass, John Christy, Benjamin Pearson, and S. Fred Singer. The Douglass et al. paper appeared in the online edition of the International Journal of Climatology (a publication of the Royal Meteorological Society) in December 2007.

    Shortly after its publication, it became apparent that the authors of the Douglass et al. paper had applied a flawed statistical significance test. Application of this flawed test led them to reach incorrect scientific conclusions.

    Together with a number of colleagues (including Gavin), I prepared a response to the Douglass et al. paper. Our response was published by the International Journal of Climatology in October 2008. (DOI: 10.1002/joc.1756) I am also appending a "fact sheet" providing some of the scientific context for both the Douglass et al. and Santer et al. International Journal of Climatology papers.)

    To my knowledge, the Douglass et al. International Journal of Climatology paper has never been retracted. Nor have the authors acknowledged the existence of any statistical errors in their work. The fact that John Christy has now cited a demonstrably-flawed scientific paper in his Congressional testimony - without any mention of errors in the Douglass et al. paper - is deeply disturbing.

    It is my opinion - and the opinion of many of my scientific colleagues - that the Douglass et al. International Journal of Climatology paper represents an egregious misuse of statistics. It is of great concern that this statistically-flawed paper has been used (and is still being used) as crucial "evidence of absence" of human effects on climate. "

    [Source: here]

    What Dr. Santer demonstrates above is incredibly troubling with regards to Christy's actions and his testimony.
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  26. This appears to be political theater.

    We are LONG past the time when the physical evidence doesn't carry the water for AGW.

    You need only look around and you see the models and climate science predictions confirmed.
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  27. Albatross@25 Troubling indeed. The statistical error in the Douglass et al. paper is pretty fundamental, it is rather surprising that the paper made it through the peer review process. The statistical error was a bit like rolling a die 100 times and getting a mean of 3.91 with a standard error of the mean of 0.1634, and then claiming that this is statistically inconsistent with the next roll of the die that gave a two. Yes, the statistical error was that bad!
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  28. Camburn - evidence would suggest otherwise - more that people uncritically accept disinformation than taxes. So you dont like taxes? Fine, choose other solutions, go nuclear, find something that matches your political philosophy. How about ending all subsidies on fossil fuel for starters? Denial is no way to approach problems however,
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  29. scaddenp:
    This is not about denial. This is about solutions.

    I have shown by the link to Florida State University that cyclones/hurricanes have decreased in number and intensity.

    I have shown by link from NOAA that precip patterns in the US have not really changed.

    I have shown by link that the winters are not unusual, contrary to some folks who think so.

    This is not denial, this is accepting what the data is showing.

    I have proposed a solution to a high percentage of carbon that is feasable and acceptable to the general public. More regulations/taxes are not the answer.
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  30. Camburn,

    "This is not about denial. This is about solutions."

    How can the folks who believe there's no problem be suddenly interested in solutions?

    "cyclones/hurricanes have decreased in number and intensity."

    The ACE index used by FSU is wind speed-duration only. By omitting precipitation events, it is highly biased.

    "precip patterns in the US have not really changed."

    There's data to show they have in fact become more intense - not necessarily frequent, but more rain in short time periods. In my part of the world, we have weeks and weeks of no rain, followed by a gully-washer. The intense rain in a short period doesn't soak into the ground. Ask around parts of the US right now, where all that snow is in the process of melting -- and there was just a late winter rainstorm.

    "winters are not unusual"

    Tell this to your denial-blog buddies, who were screaming 'worst winter in 1000 years' not all that long ago. Which side seems to now be arguing out of both sides of their mouths?

    SkS threads for all of these topics, with links to supporting documents, can be found using Search, but you already know that.
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  31. "I have shown by link from NOAA that precip patterns in the US have not really changed."

    ah well, that is O.K. then! ;o)

    "This is not denial, this is accepting what the data is showing."

    No, it is accepting what some of the data is showing, which is consistent with denial. Is there any reason to prefer the FSU study over any of the others?
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  32. Dikran @31,

    Camburn seems to be trying very hard to derail this thread-- so I do not want to entertain his attempts to do so. But, if you look at the CEI (Climate Extremes Index) that I link to a 22, it shows a distinct increasing trend since the early 70s.

    Now what I am more concerned with is the fact that Christy deliberately, knowingly mislead congress. Funny how that fact is ignored by the 'skeptics'. These findings are troubling and do not reflect at all well on the tactics, ethics and science of a prominent 'skeptic', so I can understand that the 'skeptics' want to distract form that very real problem too.
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  33. Albatross - yes, see comments #13 and #14 regarding Santer's take on Christy's testimony. I agree it's very misleading to present the flawed findings of the Douglass paper without even mentioning the fact that the paper has been refuted.

    Also interesting is that Christy was a co-author on 60% of the references in his written testimony.
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  34. Dana @33,

    "Also interesting is that Christy was a co-author on 60% of the references in his written testimony."

    Interesting,so much for considering all opinions and all of the scientific understanding. It really irks me that "skeptics" (falsely) point the finger at the IPCC for allegedly excluding "dissenting" views and then go and do stuff like this.
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  35. Albatross: "Also interesting is that Christy was a co-author on 60% of the references in his written testimony."

    Wonder who the other 40% were by.
    0 0
  36. RickG @35,

    Good question. I will have a look-- I suspect fellow contrarians and "skeptics".
    0 0
  37. RickG @35,

    Hmm, I could only find two papers (out of the 15), which to my knowledge were written by actively-publishing scientists and did not include Christy. And only one of those was by reputable climate scientists. By my count, Christy was an author in 8of the 14 peer-reviewed papers he cites. There is an Energy and Environment paper in there which I included being as peer-reviewed, but we know the debate surrounding that particularly dubious "journal".

    Christy did not reference Spencer and Braswell properly, it is incomplete.
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  38. Some notes:
    a) Tamino didnt substract AMO (but made straw men against it), and cherry picked the trend which is most positive.
    b) The "hot spot" rebuttal you have linked into doesn't account several papers, which it should have (like Christy et al, Klotzbach et al, McKitrick et al).
    c) Have you actually taken a careful look in the Dessler paper? His R^2 is 0,02 which means either that the relationship is not linear or there is not enough observations (propably both). He had nothing to publish.
    d) You dismissed Spencers arguments about forcing vs feedback with pure arm-waving (Clement et al also suffers from this spesific point), S&B 2008 and 2010 not cited and not accounted for.
    e) Science isn't about the so called "consensus". It is about testing hypothesis. Consensus is related to politics, not science.
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  39. protestant...

    Regarding"b", you need to point out which papers from these people. What about which papers were not accounted for. Just dropping names is pretty meaningless.
    0 0
  40. Protestant,

    So to detract from inconvenient truths and defend Christy's misconduct you start making a long list of accusations against others. I can only assume that means that you agree with Christy misleading congress and lying by omission.

    I'll let Dana address your red herrings and strawmen.

    AGW is supported by consilience, which goes way beyond consensus.
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  41. Protestant,

    None of what you posted. appears to have anything to do with this topic. However, I will comment one of your notes.

    e) Science isn't about the so called "consensus". It is about testing hypothesis. Consensus is related to politics, not science.

    The consensus in science is what the majority of published peer review literature supports. It has nothing to do with politics.
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  42. protestant #38

    a) Tamino didn't subtract the AMO because there's no reason to. Christy didn't subtract it either. Like ENSO, it's just another oscillation which has no impact on the long-term global temperature trend.

    You provided no evidence to support your "cherrypicking" accusation, so I'm just going to ignore it.

    b) As Rob said in #39, if you want us to consider specific papers, you'll have to reference specific papers rather than just throwing out random "skeptic" names.

    c) Yes, I wrote an article on Dessler (2010) which is linked in this post.

    d) I didn't dismiss anything. I responded to Christy's testimony, which specifically talked about cloud feedbacks. Moreover, Spencer's 'internal forcing' hypothesis is based on nothing more than correlations.

    e) Christy was the one who brought up the consensus. If you don't like it, take it up with him.
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  43. I've seen many deniers accusing Tamino of cherry picking 1975 as the start of the modern global warming period. The accusation has no merit. That year is the pivotal point where the behavior of the temperature time series changes in a totally unambiguous fashion, thus the choice is perfectly legitimate. It is justified by statistical analysis, not other considerations. Tamino has explained this a number of times and even showed the mathematical details.
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  44. Camburn - are you listening to anything? Firstly, the concern about climate is what the future will bring. If climate modelling predicted particularly bad things happening to US now that arent, then you would have a point. The concern is that climate models are doing well at predicting climate and those future consequences look ugly.

    Secondly, your also seem to be saying that no matter if US emissions are causing a problem for rest of planet, so long as they dont trouble the US, then no reason to take action. You expect us to respect this view?

    You arent convinced there is a problem, and your posting history suggests you search out reasons for believing that. Okay, but assuming that you are prepared to have your decision-making informed by data, what is the data that cause you to change your mind in the future? What indicators would look at 20 years down the track where you would think, "whoops, got it wrong".

    On the other foot, for me climate science is putting out a lot of predictions. If they turn out wrong beyond the levels of uncertainty, then I would accept (with great pleasure as an oil and coal man) that science was wrong.
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  45. I am curious. I posted a link from NOAA concerning the winter of 2009-2010. Has anyone actually read it?
    It disputes Mr. Zwiers assertion that the recent winters are tied to AGW in the US.

    As far as hurricanes/cyclones. Rain is a normal part of them is it not? Is not the destruction caused by the energy of the hurricane? Which is bore out by wind speeds etc?
    The destruction is caused by the winds. Florida State University has a site that shows intensity and numbers.
    0 0
    Moderator Response: [DB] That comment also contained material taken from a denialist disinformation site, so I personally stopped reading at that point. Material taken from original, peer-reviewed sources is best for building a credible, science-based argument here.
  46. DB:
    NOAA, at least to me, is a credible source. The University of Florida is also credible.
    As far as a disinformation site, you have lost me.
    0 0
    Moderator Response: [DB] In your comment in question, your second link was from, which serves up disinformation. Example: "NOAA February Data Confirms U.S. Has Been Cooling The Last 15 Years: -1.9°F/Century Trend" = Hokum. I applaud using credible sources such as NOAA or Florida State University, but to put those fine institutions on a par with the like of c3headlines is to de-value the contribution of your entire comment. You can do better (and you have indeed done so in other comments).
  47. "Rain is a normal part of them is it not? Is not the destruction caused by the energy of the hurricane? Which is bore out by wind speeds etc? The destruction is caused by the winds. "

    This discrepancy is discussed on the hurricanes and global warming thread. Large rain events, also very destructive, are not included in the ACE index.
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  48. Camburn,
    "I posted a link from NOAA concerning the winter of 2009-2010. Has anyone actually read it?"

    Yep, especially when I got this far:
    Still, bitter cold temperatures and blizzards of historic proportions prompted the questions: Why were there so many historic snowstorms in the mid-Atlantic region this winter? Are they evidence that global warming isn’t happening?

    No, the globe is warming. But the real story behind the mid-Atlantic’s winter isn’t about climate change, it’s about climate variability. Climate variability, the term scientists use, explains why record-breaking snowstorms and global warming can coexist. In fact, many of the weather events observed this winter help to confirm our understanding of the climate system, including links between weather and climate. ... predicting any single weather event is inherently difficult and why we don’t base our assessments of climate on any single weather event. And it shows why we can make probabilistic statements about future climate, given a long data record and a good understanding of the state of the forces that drive the system.
    --emphasis added

    Once again, the message is that specific weather events have disparate causes; but the overall warming pattern makes what were once infrequent and unlikely events more likely.

    Whoever first said, 'If you don't like the weather, wait 10 minutes' knew what he was talking about.
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  49. DB@46:
    I didn't know that the site in question was a skeptic site.
    The graph came up in another discussion and when I saw that it was NOAA data including the link I deemed it credible. I have not been to the site in question so I can't comment on it one way or the other.
    The graph only confirmed other research that I have read concerning hydrological cycles in the US. This is something that I am keenly interested in as it directly affects what I do.
    Thank you for letting me know about that site.
    0 0
    Moderator Response: [DB] A kindly word of advice: always seek out the source of any graph or data that interests you on blogs. Even well-meaning persons make honest mistakes. There are those less well-intentioned whose presentations lose fidelity when compared to the sources they claim to cite. The originating source is typically most credible. When even a credible source, such as NOAA, cites a study that interests you, check the original study (where possible) and those that cite it as a basis for further research. The true skeptic follows that route.
  50. muoncounter:
    Thank you for reading the link and commenting on it. The winter weather is weather and not in any way tied to AGW.

    The only reason I brought this up is that Mr. Zwiers brought it up in his testimony.
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