Climate Change: Is it Real and Important?

On October 16, 2015, I published an essay that was skeptical of claims made by the IPCC and others promoting a man-made warmer future that doesn’t look very likely to happen. Since then, over 50,000 people have seen that essay, and almost 9,000 people have read it. I have had many messages of thanks, and a few people even volunteered to help.

Then, on October 29, a group of global-warming enthusiasts published a fairly lengthy and standard list of arguments entitled Climate Change is Real, and Important. I would call these people “true believers,” because they have a fixed position and no room for learning anything new. Their goal was to discredit me and my essay; they have followed up on Twitter with the same name calling and scapegoating.

It’s difficult, and time-consuming, for lay readers to dive into the scientific studies and data, so they rely on claims made by authorities and news media. Since this topic is so highly politicized, the views are extreme. The mainstream view is that humans are creating a hellish future for the planet. My article simply looked at those claims and found that they were the result of computer models built on many unproven assumptions with huge ranges, and those models haven’t been right since they were published. We just don’t know, and it’s less and less likely that the mainstream predictions of the IPCC are correct. Most of the observed “extreme” events we see today are of both the normal, every-day variety and the “black swan” variety that would have happened anyway. Our planet may indeed be capable of regulating its own temperature. There are countless examples of scary headlines getting a lot of press. When reality turns out to be different, these new findings never get the same coverage. In the media, “if it bleeds, it leads,” and this causes a great deal of confirmation bias and warped messages.

It seems wrong to let this rebuttal stand without a counter-rebuttal. Fortunately, two people have come to help.

The first is Tim Hunter, who thought the rebuttal was so unfair he wrote a blog post about it, trying to set the record straight. Thank you, Tim.

The second is an incredibly detail-oriented guy named Bob Johnson, who took the time to go through the attack piece and craft his own rebuttal. Bob gets upset when people lie. Bob wrote the first draft, then he and I collaborated on this response. It’s really just for people who have read the original essay and the attack piece. Thanks again to Bob for his hard work …

Our Rebuttal
In what follows, the original words from the rebuttal are in regular weight and our responses are in bold

Yet the scientific consensus that we are changing the climate […]

Science is not determined by consensus. This is the bandwagon fallacy. The popular claim that 97% of scientists believe in man-made global warming is a myth. Even so, almost all scientists expect a small man-made contribution to warming. David addressed this in his essay.

[…] constantly being challenged by those who have financial or other interests in the continued use of fossil fuels.

Neither David nor I have any such interests — this is a clear factual error. Really they’re just attempting to smear anyone who disagrees.

Denial of science is a sufficiently well developed industry […]

Merely asserting ones’ opponents are engaged in denial of science doesn’t change the facts. There are 1,350+ peer-reviewed scientific papers that support various skeptical positions that challenge the mainstream conclusions.

[…] more than 170 specific myths about the science have been identified.

This links to a web site with a well-known bias toward climate alarmism. You can read some criticism of this website here1, here2, here3, here4, and here5, for example.

David Siegel claims to have identified a number of “smoking guns” in his arguments that climate change is not real.

This claim is false. David does not deny climate change. It is real, and it is, as far as scientists can tell, very small. There are bigger problems that deserve our attention.

For example, he claims the Hockey Stick temperature chart is wrong.

True, and he supports what he says with hard science. Go to David’s original essay, search for “Hockey Stick,” and judge for yourself.

He claims that it was warmer in medieval times, 1,000 years ago, than it is today.

True, and this is known to anyone who is willing to look at the data. There are several dozen peer-reviewed papers that make a clear case for the medieval warm period (MWP) being a global event. CO2Science also has an excellent resource page.

[Siegel] commits a logical fallacy when he writes that in the past the change in CO2 lagged the change in temperature, implying that it therefore cannot cause the rise in temperature we see today.

False. David does not claim that just because historical climate records show CO2 lagging temperature increases that this means CO2 can’t cause warming. As far as we know today, CO2 historically lagged the change in temperature. There are at least nine peer-reviewed papers showing this, and even their own web site agrees: “based on Antarctic ice core data, changes in CO2 follow changes in temperature by about 600 to 1000 years” As David says, there is no direct cause and effect, as many people are led to believe.

David Siegel makes false accusations that scientists are fudging and cherry picking data.

No blanket claims like this are made. What David pointed out is a single specific case where scientists really did engage in disreputable behavior, specifically for the Hockey Stick.

Even bigger red flags pop up when you read that David Siegel doesn’t “trust” the most prestigious general science journals, Nature and Science.

Quite the contrary. An honest reader can read a peer reviewed article pointing out measured publication bias. There are entire books about the failure of expert predictions. The most recent editor of Science has engaged in activism and has violated their own publication rules by publishing papers fitting a particular agenda without archiving the relevant code and data. Read Roger Pielke Jr.’s book on how Nature and Science are biased. These issues should be a source of concern for anyone who worries about how the reputation of science is being damaged by such practices at formerly prestigious journals.

When he says that some of the most highly regarded scientific institutions, NASA, NOAA and the Intergovernmental Panel on Climate Change (IPCC) are not to be trusted […]

David doesn’t make such blanket claims, he points out specific concerns regarding data manipulation, activism violating institutional policies going unchecked, politics being represented as science, etc.

In effect David Siegel said he doesn’t trust any experts in climate science.

False. David cites dozens and dozens of expert climate scientists.

Instead of published research, Siegel places his trust in blogs maintained by people having no expertise in climate science or any science […]

False. David is pro-science and refers to many highly credentialed climate scientists. A bit of irony though: the claim is being made by people who provide dozens of links to a blog web site run by activists, owned by a cartoonist.

David Siegel places his “trust” in political organizations, such as the Heartland Institute

False. David merely recognizes that some reputable scientists work for that institution. Nobody is placing blind “trust” in any institution. Also note their use of the genetic fallacy: judging something on the basis of where it comes from rather than content.

[…] we asked cognitive scientist Professor Stephan Lewandowsky of Bristol University, what prompts people in general to reject mainstream climate science […] “The most important factor […] is not evidence or data but their ‘worldviews’; […] If scientific facts challenge those worldviews, then this may set in motion an effort to deny those inconvenient facts.

False. David previously believed in climate catastrophe and even wrote a book about his environmental concerns. He is a Democrat, a vegan, and he believes government is important for protecting the environment. He wrote the article they’re attacking to help other people check their assumptions and sources. Don’t be misled by this hit piece; look at the data and judge for yourself.

Stephan Lewandowsky added that dismissing experts as David Siegel did is one way of managing the dilemma of trying to maintain intellectual respectability.

This is blatant hypocrisy. They seem to reject 1,350+ peer-reviewed papers, and they reject many climate science experts as well (e.g. Dr. Lindzen, Dr. Soon, Dr. Pielke, Dr. Curry, and so on). This is why it’s important to focus on the facts and look at the issues and data skeptically.

[quoting Lewandowsky] “Given that climate change is one of the most thoroughly established scientific findings of recent decades […]

Nobody is denying climate change. The climate is changing. Not much. Not quickly. And not lately.

One technique commonly used is that of calling on fake experts.

At the end of his essay, David thanks Dr. Richard Lindzen, with such credentials as Professor of Atmospheric Sciences at MIT, who has published hundreds of scientific papers and written several books. He also contributed to at least one of the IPCC reports. He received a degree in physics from Harvard, another degree in mathematics, and his PhD thesis was on atmospheric dynamics. He has worked for various prestigious universities, and at one time worked for the National Center for Atmospheric Research. He is the author of a standard textbook on atmospheric dynamics. He served on an 11-member panel organized by the National Academy of Sciences to create a report titled “Climate Change Science: An Analysis of Some Key Questions.” I mention all this background to make it very clear that it would be completely ridiculous to dismiss the informed opinion of such a distinguished climate scientist. Lindzen and others cited are not “fake” experts. This is just a trick for slandering anyone who disagrees, and it’s an example of the no true Scotsman fallacy.

Articles which dispute climate science are often full of logical fallacies […]

Note that the only supposed fallacy they’ve called attention to so far wasn’t actually a fallacy at all. They seemingly misread or intentionally misrepresented what was being said (see above about CO2 historically lagging temperature).

David Siegel wrongly claims that scientists have cherry picked data.

No, David has not made blanket statements like this, he’s given specific examples you can see for yourself in his essay.

[…] people who reject climate science will claim that scientists around the world are engaged in some sort of giant global hoax.

False. David merely pointed out specific activist claims that distort the science, and calls out specific mistakes that have been made in some past science papers that are popularly believed in spite of having been refuted. It’s not the first time. He encourages people to watch Noam Chomsky’s documentary, Manufacturing Consent.

Warming is proceeding very quickly compared to previous changes in Earth’s history.

Actually the rate of warming is quite modest, and down quite a bit in the last 17 years in spite of a continued massive increase in CO2. See here.

The mean global surface temperature is increasing, very quickly.

This is unsupported extremism. Global surface temperature is increasing, but only by a small amount, and rather slowly. Over the last 18 years there has been virtually no warming at all.

Sea level is rising. This is because the oceans are getting warmer (expansion of water) and ice sheets and glaciers are melting.

Consider this report:

The Arctic ocean is warming up, icebergs are growing scarcer and in some places the seals are finding the water too hot, according to a report to the Commerce Department yesterday from Consulafft, at Bergen, Norway.

Reports from fishermen, seal hunters and explorers all point to a radical change in climate conditions and hitherto unheard-of temperatures in the Arctic zone. Exploration expeditions report that scarcely any ice has been met as far north as 81 degrees 29 minutes. Soundings to a depth of 3,100 meters showed the gulf stream still very warm. Great masses of ice have been replaced by moraines of earth and stones, the report continued, while at many points well known glaciers have entirely disappeared.

Very few seals and no white fish are found in the eastern Arctic, while vast shoals of herring and smelts which have never before ventured so far north, are being encountered in the old seal fishing grounds.”

That was published in the Washington Post in 1922. That’s right, 1922.

It’s true that sea levels are rising, but very slowly. They also failed to mention that Antarctica’s ice is actually increasing.

Heat waves are worse than they used to be.

Says who? There are no studies showing a conclusive link between global warming and increased frequency or intensity of storms, droughts, floods, cold or heat waves. “Used to be” — when?

Tropical cyclones (hurricanes and typhoons) are expected to become stronger. Some scientists feel this is already happening.

Notice the weasel words “expected” and “some scientists feel” — these are classic rhetorical tricks to hide the fact that they don’t have hard science on their side. And why don’t they mention that hurricane activity is at a 45 year low?

[quoting Dr. Mann] “The authoritative scientific assessment to date (the 5th report of the Intergovernmental Panel on Climate Change) concludes that human activity has been the “DOMINANT cause” of the warming of the past half century. […]”

The IPCC assessment is the result of a political process, not a scientific one. AR5 actually makes a weaker case than AR4, according to Dr. Curry. Their attribution and confidence claims fly in the face of the unexplained 18+ year hiatus in warming that is contrary to their models, the unexplained increase in ice in Antarctica that is contrary to their models, etc. David gives specific sources for these claims.

Scientists can extend climate data back about 800,000 years using ice cores. Even if there were brief very warm periods over this time, they would not rival the surface temperatures we expect over coming decades.

They’re implicitly admitting that there have been warmer periods in the past. Also, they’re appealing to the output of computer models that have failed to predict the conditions we observe today and trusting these unskillful models to reliably predict conditions in the distant future. Science? — or activism?

Siegel’s “evidence” that it [the hockey-stick graph] was wrong was a report prepared by the Heartland Institute […]

False. David cites many sources including peer-reviewed articles published in Geophysical Research Letters, Proceedings of the National Academy of Sciences, Inter-Research Science Center, etc.

However, each new reconstruction [of the Hockey Stick], using different data, is remarkable [sic] similar to the ones that went before.

False. When people use the same faulty methodology as the original study, yes of course it produces the same results. The methodology has been refuted in peer reviewed literature, for example here.

The PAGES 2k reconstruction is based on a lot more evidence than was available in 1999, yet shows how estimates have changed very little over time.

Note in their PAGES 2k graphic the red line is not from reconstructions — read the description under the chart. Look closely at where the blue/green line ends on the right. Look at the magnitude of the scale on the left. And pay attention to the width of area of uncertainty (the shaded area). What do you see? That’s right, a subset of temperature proxies shows a tiny amount of warming…which nobody denies. Notice how wide the uncertainty is. Notice how the proxies that show the Medieval Warm Period are deemphasized because they would show vastly higher temperatures in the past. So what does this graphic really show us? That some uses of graphs can be quite misleading.

The chart below shows how sea surface temperatures have risen in recent decades […]

Note the intentional misuse of scale to visually exaggerate the data in the chart, where huge bars are representing absolutely tiny numbers. And here’s the kicker: read the title of that chart. They set the baseline (the “zero” value) to be the average from 1961–1990, and then showed how values are different from that specific carefully chosen average. One should ask: why was that specific average chosen? What are the sources of these measurements? In what ways, if any, are they adjusted? There are also some concerns about changes in data source over time that aren’t accounted for, see here.

The first conclusion it lists is that it is not yet possible to determine a detectable impact of climate change.

Exactly. So any claims that a particular current weather phenomenon (droughts, hurricanes, etc) are due to climate change would be spurious — I’m glad you agree.

It is likely that by the end of this century, human-caused warming will result in more intense tropical cyclones […]

This is speculation, not science. How do they know what the climate will be decades from now?

However, there is evidence that the increase in [topical cyclones] strength has already started to happen […]

This is highly speculative. The report cited is based on data that only covers the Atlantic Ocean, and only 1988–2006 and thus has no knowledge of the countless hurricanes that occurred before 1988, or anywhere else in the world. Such a weak data set can’t be the basis of reliable general predictions. Even so, their speculative results only suggest a tiny increase in maximum wind speed. We’re in a prolonged major hurricane drought that goes against the predictions of catastrophe.

There is general agreement among experts that there are likely to be more high category (Category 4 and 5) storms as the world continues to warm […]

The expert most often cited is Kerry Emmanuel of MIT. The statistical methods used by Dr. Emmanuel for his 2005 estimations are refuted by other scientists. There has been no increase in intensity or quantity of storms; as David mentioned, we’re in a bit of a tropical cyclone drought in recent times. As this well reasoned paper shows, 1) so far there are no signs that hurricane activity is due to man-made CO2, and 2) we just don’t have enough information to model future hurricane activity accurately.

Kerry’s more recent work claims there will be some increase in tropical cyclone intensity but less than previously thought. Judith Curry’s response is that we aren’t making good decisions about what to do, given the uncertainties involved.

Events like Hurricane Patricia are a warning sign of what is to come.

This is blatant fear-mongering. Remember a few paragraphs ago when they admitted “it is not yet possible to determine a detectable impact of climate change.”? This is an appeal to emotion and recent headlines. The future of our planet is not determined by claims that make good headline copy.

What scientific research can and does show, is the likelihood of extreme events being exacerbated by human-caused warming.

False. They’re referring to predictions made by unskillful computer models. In fact these models are known to not match observation, and thus aren’t skillful — they don’t have predictive value. This is pure speculation.

In a supplement to the Bulletin of the American Meteorological Society (BAMS), scientists reported that human-caused global warming very likely played a role in the following extreme events in 2012 and 2013 […]

False. The report makes no such bold claim — read it yourself. The report defines the extreme events via some very general attributes, such as via the geopotential height averaged over a huge area. They then run several different computer models with different input parameters, where some inputs are characterized as a “natural” component, and another is characterized as an anthropogenic component. They run the many different models multiple times and then report how often the very general attribute occurs. This does not establish causation in the real world.

[IPCC] “It is likely that human influence has substantially increased the probability of occurrence of heatwaves in some locations.”

[IPCC] “There is only medium confidence that the length and frequency of warm spells, including heat waves, has increased since the middle of the 20th century mostly owing to lack of data or of studies in Africa and South America.”

Heat waves in North America: [IPCC] “Medium confidence: increases in more regions than decreases, but the [decade of the] 1930s dominates longer term trends in the USA”

Regional factors dominate, and in the past there have been temporary periods of warming (e.g. 1930s). We don’t have good enough data to make strong general statements about heat waves around the world. Furthermore, cold weather kills about 20x as many people as hot weather, and even the speculative increases in heat waves are very small increases. Here are some other statements directly from the IPCC AR5 WGI Chapter 2 on extremes:

  • “Current datasets indicate no significant observed trends in global tropical cyclone frequency over the past century … No robust trends in annual numbers of tropical storms, hurricanes, and major hurricanes counts have been identified over the past 100 years in the North Atlantic basin”
  • “In summary, there continues to be a lack of evidence and thus low confidence regarding the sign of trend in the magnitude and/or frequency of floods on a global scale”
  • “[…] the current assessment concludes that there is not enough evidence at present to suggest more than low confidence in a global-scale observed trend in drought or dryness (lack of rainfall) since the middle of the 20th century ... Based on updated studies, AR4 conclusions regarding global increasing trends in drought since the 1970s were probably overstated.”

[…] no natural explanations for the change in temperature, the enhanced greenhouse effect seen from satellites […]

Satellite data shows no warming for 18+ years.

The dominant cause [of warming] is the very large increase in atmospheric carbon dioxide, a greenhouse gas.

How do you know? Based on what evidence? Based on a movie? A TED talk? David has given several peer-reviewed references showing that carbon dioxide most likely contributes a very small amount of warming; current research focuses on solar activity.

Global mean surface temperature is already around 1 °C higher than it was in the 1850s […]

This is probably about right. I wonder how it got started back in 1850? Could it have anything to do with the general warming trend over the past 400 years, coming out of the Little Ice Age?

You might ask, why trust climate models? The answer is that they provide insight into climate, and what we can expect as the world warms.

The authors have linked to an article that says:

Some voices in the public debate over climate science have been critical of the fact that there is no standardized, independent testing protocol for climate models like those used for commercial and engineering applications. Climate scientists have responded that climate models are so different as to make such an “independent verification and validation” process incompatible.”

In other words: independent verification and validation is hard. It goes on to say:

Improving the model means better simulating physical processes, Schmidt says, which doesn’t necessarily improve the large-scale match with every set of observations. ‘There are always observational datasets that show a mismatch to the model — either regionally or in time,’ Schmidt explained. ‘Some of these mismatches are persistent (i.e., we haven’t found any way to alleviate them); some are related to issues/parameters that we have more of a handle on, and so they can be reduced in the next iteration. One problem is that in fixing one problem one often makes something else worse.’”

Does this sound like the kind of software you want to trust for making trillion-dollar decisions? For telling your children what their future will be like? The models have failed to predict what we actually see, look at the data.

The claim that models are not yet skillful is certainly incorrect.

False. A skillful model would successfully predict future observations. Out of 90 CMIP5 models, not one predicted what we actually observe. Read Climate Models Fail by Bob Tisdale.

A model being skillful does not mean that the model is 100% “right” […]

True. The right question to ask is about uncertainty ranges. Current observations showing a very long pause in warming is outside of uncertainty ranges. Even NOAA says (page 23):

”The simulations rule out (at the 95% level) zero trends for intervals of 15 yr or more, suggesting that an observed absence of warming of this duration is needed to create a discrepancy with the expected present-day warming rate.”

Given the fact that satellite measurements show no warming for longer than the period required for a discrepancy, the models are unskillful. Saying they are skillful onstage at TED doesn’t make them skillful.

Predictions, in the late 1980s, of future warming in response to increasing anthropogenic emissions have also been shown to have been skillful (Hargreaves 2010).

Let’s read it. What does that report actually say?

“Analysis of the Hansen forecast of 1988 does, however, give reasons to be hopeful that predictions from current climate models are skillful, […]” [emphasis added]

It goes on to say:

One challenge for those studying uncertainty is the ongoing incorporation of additional poorly understood feedbacks in the models which provide more sources of uncertainty to be investigated […] it is only by better understanding the processes and inclusion of these processes in the models that the best models can provide predictions that are both more credible and closer to the truth

David Siegel’s fourth wrong claim was that global temperature is more highly correlated with solar radiation. That is incorrect. It is currently the second most popular myth listed at

False. If you follow the link about the “myth” it says in part:

“The only way to blame the sun for the current rise in temperatures is by cherry picking the data. This is done by showing only past periods when sun and climate move together and ignoring the last few decades when the two are moving in opposite directions. ”

Whereas David explicitly shows all the recent decades. In fact, knowing that such misinformation is so common, David says:

Note that this graph accurately shows the most recent cooling trend since 1998 without any hand waving.

Not only does this suffer from the correlation doesn’t imply causation problem, it’s not correct.

What is demonstrated is that solar forcing matches observations far better than CO2 concentration. As David says, we have more to learn, but it’s probably better to start with the more influential factor — solar radiation.

The science shows that, contrary to what David Siegel wrote, solar forcing had a small negative influence on climate between 1980 and 2011.

The “science” shows that? Willie Soon’s graph shows a small negative trend in recent times, which in fact matches what we observe: that global mean surface temperatures have been flat for 18+ years.

Based on paleoclimate studies, equilibrium climate sensitivity (how much the planet will eventually warm after doubling atmospheric CO2) is likely to be between 2.2 °C and 4.8 °C.

More recent peer-reviewed studies have set the equilibrium climate sensitivity (ECS) much lower, e.g. 1.093C. You can find 15 peer-reviewed papers that estimate ECS to be between 0.3–1.99C — lower than the lowest estimate of the IPCC.

This sixth objection of David Siegel is commonly raised by people who, for mostly ideological reasons, do not want to take action to mitigate climate change. He objected to the word “pollution” […]

What ideological reasons? As David says, “I now think there probably is no climate crisis and that the focus on CO2 takes funding and attention from critical environmental problems.” People like David object to calling CO2 a pollutant because CO2 is not a pollutant. It is not poisonous, and it is required for plants to grow. Humans breathe out CO2, and plants breathe it in. Labeling CO2 as a pollutant is misleading. David is trying to help the environment by eliminating bias in decision making on how to spend limited resources.

Whether warming or sea level rise at any time is from natural forces or human activity, there is always a cause. Saying “natural” means little unless you can say what natural (or other) force is causing the change.

This is an interesting statement. What’s forcing Americans to be so obese? Many researchers have looked at this, and we still need more pieces of the puzzle before we know the true cause. What causes Planck energy or dark matter? This is what science is for — trying to be less wrong as time goes on. David can apply the same logic to you: saying “man made” means little unless you can say what’s really causing the change. Even though the science is “settled” in your minds, thousands of scientists worldwide are still trying to put cause and effect together. We don’t turn off the satellites and go home after a political body wins a Nobel prize.

Furthermore, sea level rise is not correlated with CO2 rise, and sea level is continuing a trend that started long before industrialization — look at post-glacial sea level rise. The climate has warmed a tiny amount, and we can reasonably expect this to have increased sea level by a tiny amount. Sea levels have been slowly rising since the last ice age, and we need to adapt to this change. Reasonable predictions suggest for 5–20cm rise by the end of the century — on par with sea level rise that occurred in pre-industrial times.

They found that the linear trend from 1900 to 2009 was 1.7 ± 0.2 mm a year. For the period 1993 to 2009 they estimated the rise to be 3.2 ± 0.4 mm a year.

Quite possibly true. Note how absolutely tiny these numbers are.

However, seas are expected to rise a lot faster and higher as the ice sheets in Antarctica and Greenland melt more rapidly.

This is speculative fear-mongering. More recent reports actually show Greenland ice sheet melt is decelerating. And historical data shows Greenland’s temperature fluctuates all by itself and has for 1,000+ years (indeed, it was warmer there 1,000 years ago!). In 2015 the Antarctic sea ice reached new record maximum. Not a convenient fact when you’re trying to push a message of global warming is it?

Yes, there is natural variation of weather and climate in the Arctic. The bigger impact over time will be from human-caused global warming.

How do you know that? From reading the New York Times? There are historical reports of Arctic ice retreating back to unheard of lows in the 1920s, only for it to grow back. The reason the Arctic and Antarctic ice grows and shrinks to precisely the extent they do, and when they do, is poorly understood.

David Siegel links to an article in Canadian Geographic about polar bears. The article is nuanced, and doesn’t support what he implies, that global warming won’t impact wildlife in the Arctic.

False. David points out that polar bears are doing fine, populations are increasing and resilient, and that international fishing and seal hunting quotas have more to do with polar bear numbers than temperature does. Anyone interested should read that “nuanced” article — it’s an eye-opener.

This year there is yet another major coral bleaching event underway.

No doubt. The oceans have been slowly warming since the end of the last ice age, and as this happens one might reasonably expect additional coral bleaching. However, new studies suggest coral reefs can adapt. The actual cause of warm waters that leads to bleaching are big El Niño and La Niña events like we saw in 1998–1999 — not CO2.

The claim that the IPCC is political is one of the misleading tenets of the “climate conspiracy” theories that circulate around the Internet. […] The Intergovernmental Panel on Climate Change (IPCC) is a scientific body.

False. The IPCC doesn’t claim to be conducting scientific research. At best, the IPCC can be said to summarize a carefully chosen subset of existing scientific research (and Greenpeace pamphlets). To fact-check the IPCC, look at the peer-reviewed literature outside the IPCC. The IPCC models predicted more sea level rise than has been observed. The IPCC models predicted more global warming than has been observed: no warming for 18+ years now. The IPCC has been exposed to be a political organization by its own members — scientific truth isn’t negotiated in the dead of night behind closed doors.

Chris Landsea, a hurricane expert, resigned from the IPCC after a lead author for the IPCC and its chairman claimed that there would be more intense and more frequent storms as a result of man-made greenhouse gases. In his resignation letter, he wrote “I personally cannot in good faith continue to contribute to a process that I view as both being motivated by pre-conceived agendas and being scientifically unsound.”

There is a growing list of scientists who have resigned from the IPCC on the grounds that “scientific conclusions are re-written by politicians and presented to the public as valid science.”

Here are 1,350+ peer-reviewed studies questioning the science behind the IPCC.

It will be obvious to readers that, because the scientific report has been accepted by the 193 member countries, it can hardly be described as “political”.

This is ridiculous. It should be obvious to readers that what politicians are willing to accept says absolutely nothing about science and everything about politics.

Twenty years ago, almost every cardiologist in the world (97 percent!) would have told you that saturated fats cause heart disease. They were wrong. Science doesn’t move forward by voting.

Either a conspiracy involving thousands of people has been foiled by a lone web design author […]

False. There is no conspiracy. The IPCC is a political body. It’s true that speaking against the IPCC narrative will put a scientist’s career in jeopardy — that’s not how science should be done, that’s how politics is done. That’s not to say it’s all bogus — of course not. There are many honest and very intelligent scientists that are helping to include legitimate research results in IPCC reports. But any honest investigator has to look skeptically at all sources of information.

Rather than be swayed by scientific evidence, they decide that the data must be fudged, and that none of the thousands of scientific experts in disciplines related to climate can be “trusted”.

It would be crazy to assume all data as fudged, or that no scientists can be trusted — nobody is suggesting that. All that David is suggesting in his essay is that we all be a little skeptical. Don’t take scary headlines as gospel — see if there are any well-evidenced rational arguments against it. Be guided by reason and facts, not by rhetorical tricks or fallacious appeals to emotion.

The subject is science, not religion.

I agree completely. So ask yourself: what evidence would be required to change your belief? Be open-minded and follow the data wherever it leads. Getting all your answers from may not be in the best interest of humanity or the planet’s future.

Finally, I note that this group made no mention of the two metastudies David cites. Why not?

What’s Next?
Hi, it’s David, I’m back. This has been a fun little exercise in rhetoric and fact checking. My immense thanks to Bob for taking the lead on this response. If tomorrow we learn that all the solar research was wrong and we really need to look more carefully at CO2, I’ll write a big piece about that and support the effort. On the other hand, if we go another ten years without the prophesized warming, will the prophets then repent?

I’m working on another project on this topic I hope to announce soon. In the meantime, I’m not really paying attention to the endless Twitter and email attacks. I’d rather answer questions from people who seem interested in learning something new. If you have questions after reading all this, feel free to contact me:

Finally, thank you to the many people who have come out in support of me and my essay. I’m sure there are thousands more who haven’t contacted me, but I know you’re out there. I wish we didn’t have to do this — I wish we could set better priorities and get on with helping the environment and the future of humanity. Those of us who believe in and defend Rationality must continue to spread the word and try to influence policies. I urge you to do so in your own way.

For those who have read my essay and this rebuttal and want to learn more, please see Bob Tisdale’s new, free ebook, On Global Warming and the Illusion of Control.

Please send people to to decide for themselves.

Thank you.

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David Siegel

Provocateur, professional heretic, slayer of myths, speaker of truthiness to powerfulness, and defender of the Oxford comma.