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The Earth Is Warming And Human Activity Is The Primary Cause: The Climate Science Paradigm Grows Stronger

By Climate Guest Contributor on November 16, 2012 at 2:00 pm

"The Earth Is Warming And Human Activity Is The Primary Cause: The Climate Science Paradigm Grows Stronger"


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by Dr. James Powell, via Science Progress

Polls show that many members of the public believe that scientists substantially disagree about human-caused global warming. The gold standard of science is the peer-reviewed literature. If there is disagreement among scientists, based not on opinion but on hard evidence, it will be found in the peer-reviewed literature.

I searched the Web of Science, an online science publication tool, for peer-reviewed scientific articles published between January first 1991 and November 9th 2012 that have the keyword phrases “global warming” or “global climate change.” The search produced 13,950 articles. See methodology.

I read whatever combination of titles, abstracts, and entire articles was necessary to identify articles that “reject” human-caused global warming. To be classified as rejecting, an article had to clearly and explicitly state that the theory of global warming is false or, as happened in a few cases, that some other process better explains the observed warming. Articles that merely claimed to have found some discrepancy, some minor flaw, some reason for doubt, I did not classify as rejecting global warming.

Articles about methods, paleoclimatology, mitigation, adaptation, and effects at least implicitly accept human-caused global warming and were usually obvious from the title alone. John Cook and Dana Nuccitelli also reviewed and assigned some of these articles; John provided invaluable technical expertise.

This work follows that of Oreskes (Science, 2005) who searched for articles published between 1993 and 2003 with the keyword phrase “global climate change.” She found 928, read the abstracts of each and classified them. None rejected human-caused global warming. Using her criteria and time-span, I get the same result. Deniers attacked Oreskes and her findings, but they have held up.

Some articles on global warming may use other keywords, for example, “climate change” without the “global” prefix. But there is no reason to think that the proportion rejecting global warming would be any higher.

By my definition, 24 of the 13,950 articles, 0.17 percent or 1 in 581, clearly reject global warming or endorse a cause other than CO2 emissions for observed warming. The list of articles that reject global warming is here.

The 24 articles have been cited a total of 113 times over the nearly 21-year period, for an average of close to 5 citations each. That compares to an average of about 19 citations for articles answering to “global warming,” for example. Four of the rejecting articles have never been cited; four have citations in the double-digits. The most-cited has 17.

Of one thing we can be certain: had any of these articles presented the magic bullet that falsifies human-caused global warming, that article would be on its way to becoming one of the most-cited in the history of science.

The articles have a total of 33,690 individual authors. The top ten countries represented, in order, are USA, England, China, Germany, Japan, Canada, Australia, France, Spain, and Netherlands. (The chart shows results through November 9th, 2012.)

Global warming deniers often claim that bias prevents them from publishing in peer-reviewed journals. But 24 articles in 18 different journals, collectively making several different arguments against global warming, expose that claim as false. Articles rejecting global warming can be published, but those that have been have earned little support or notice, even from other deniers.

A few deniers have become well known from newspaper interviews, Congressional hearings, conferences of climate change critics, books, lectures, websites and the like. Their names are conspicuously rare among the authors of the rejecting articles. Like those authors, the prominent deniers must have no evidence that falsifies global warming.

Anyone can repeat this search and post their findings. Another reviewer would likely have slightly different standards than mine and get a different number of rejecting articles. But no one will be able to reach a different conclusion, for only one conclusion is possible: Within science, global warming denial has virtually no influence. Its influence is instead on a misguided media, politicians all-too-willing to deny science for their own gain, and a gullible public.

Scientists do not disagree about human-caused global warming. It is the ruling paradigm of climate science, in the same way that plate tectonics is the ruling paradigm of geology. We know that continents move. We know that the earth is warming and that human emissions of greenhouse gases are the primary cause. These are known facts about which virtually all publishing scientists agree.

James Lawrence Powell is the author of The Inquisition of Climate Science. Powell is also the executive director of the National Physical Science Consortium, a partnership among government agencies and laboratories, industry, and higher education dedicated to increasing the number of American citizens with graduate degrees in the physical sciences and related engineering fields. This article is cross-posted with permission with the Columbia University Press blog.

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8 Responses to The Earth Is Warming And Human Activity Is The Primary Cause: The Climate Science Paradigm Grows Stronger

  1. Jack Burton says:

    The evidence science has been able to amass over the last few decades on the subject of CO2 accumulation in the atmosphere that is a direct result of fossil fuel burning is pretty much cut and dried at this point. I am always on the lookout for some clear evidence that global warming is NOT taking place due to fossil fuel burning. I even read skeptic’s claims and try and find where they successfully debunk the prevailing theory. Some sound good, but they never pan out, they never deliver the data and evidence. They seem to always be diversionary tactics, looking to take the debate off know science and take it down a blind road in order to buy time for the fossil fuel industry to keep up business as usual.
    This year’s Arctic sea ice melt and the last two years of extreme weather in the world are making me believe we are already past the point of stability, the climate is shifting to a new normal driven by CO2 that briefly passed 400PPM in the northern hemisphere this spring. To me, 400PPM is a level that is so far out of the level that our long term stable climate was based on that we are never going to see that stable climate again.
    The storm Sandy was a fitting end to the summer of 2012, this storm was so out of the norm, that even the loud mouth skeptics had to remain silent by and large. Proof enough that real world events are leaving the skeptics and the paid liars, I mean fossil fuel industry PR professionals behind in the dust.

  2. Dr.A.Jagadeesh says:

    Excellent post on Earth Warming and humans contribution to it.
    Dr.A.Jagadeeswh Nellore(AP),India
    E-mail: anumakonda.jagadeesh@gmail.com

  3. perceptiventity says:


    ‘Are the climate deniers right? Are some scientists colluding with government to hide the truth about climate change? “Yes”, according to top British scientist Kevin Anderson – but not the scandal you’ve heard about. Top scientists and government reports won’t tell you we are heading toward catastrophic climate change. Emissions are skidding out of control, leading us to a world six degrees Centigrade hotter on average, much faster than anyone thought possible. Why doesn’t the public know?

    Why are world conferences still talking about staying below 2 degrees, as though that is possible?

    In a devastating speech at Bristol University Tuesday November 6th, 2012, Dr. Kevin Anderson accused too many climate scientists of keeping quiet about the unrealistic assessments put out by governments, and our awful odds of reaching global warming far above the proposed 2 degree safe point.

    In fact, says Anderson, we are almost guaranteed to reach 4 degrees of warming, as early as 2050, and may soar far beyond that …

    • Greatgrandma Kat says:

      It’s not a secret. If you follow this blog or read any of the 2012 science news that is what all of them say. The positive feedbacks are kicking in but sooner than the models say it should, there is no conspiracy to leave the world uninformed, just disinformation from fossil fuel interests to hopefully convince people it isn’t happening at all or that it has a natural cause and will revert to our former climate any day now and above all that fossil fuels are not to blame. All creditable climate scientists have been screaming from the rooftops for the last 5 years telling goverments and people to wakeup before it’s to late.

  4. Mike Roddy says:

    Quality climate scientists know what is going on. The problem is the US media. A free press is based on multiple sources educating the public. In prior centuries, people paid a few cents for a newspaper, and editors had at least some respect for the truth.

    Nowadays, media is an advertiser driven enterprise. The biggest advertisers are energy intensive, and influence and sometimes dictate content. The cost of TV bandwidth and
    newsprint keeps ownership concentrated. When a decent cable network appears, such as Discover or Animal Planet, it is swallowed by a right wing conglomerate. Koch corrupts PBS and National Geographic.

    College kids and curious members of the public cannot overcome the distortion of the public dialogue. Most Americans are in the dark due to deliberate obfuscation. This will kill millions of people, and has to stop.

  5. Dr. Thomas Pringle says:

    Notice that the 2012 column is unintentionally misleading — it implies that fewer articles will be published in all of 2012. That defies common sense.

    If you take 1400 cites so far and divide by the 313 days to the Nov 9 cutoff, then multiply by 365 to get the year’s total, that works out to merely 1,637 cites for the year.

    In fact by simple curve-fitting, the total for 2012 will be over 1900. Research activity is swelling.

    The problem here is the survey was cut off on Nov 9 but Web of Science lags unevenly in its coverage because of how journals release their articles to WoS. Thus the most recent publication date might have been Oct 25 (instead of Nov 9) but the count would still not be comprehensive for Oct 25.

    The best fix would be to top off the 2012 column with the extra cites (different color supplemental rectangle) that gives 2012 its predicted total.

  6. Rabid Doomsayer says:

    It is warming, it is us, and it is going to be bad. Just how bad is up to us.

    Tick, tick, tick, tick.

  7. Dan B says:

    Dr. Powell;

    Almost 14,000 to 24 is enormous. It would be great to have some context with which to compare these numbers to other areas of research. Research on smoking’s links to cancer is one idea.

    My father was a research chemist. His scientific magazines would publish an interesting article and a few months or years later it would be shot down by another experiment or discovery. The theory of tectonics went through a lot of debate. My expectation is that climate research has been astonishingly clear by comparison to other topics.