Has the climate change debate reached a tipping point?

In recent months, mainstream scientists have been more willing to speak out about speculation that global warming may mean that Earth’s climate is on the verge of a possibly catastrophic “tipping point,” beyond which future human technology will not be able to undo the effects of past and ongoing excesses. People who view this as a left-wing ideological issue may have to change their tone, now that a group of prominent evangelical Christians have called for environmental action before it is too late.

The late Carl Sagan would smile. In Billions and Billions, his final book written a decade ago, Sagan spoke of the need for science and religion to come together as stewards of planet Earth. He debunked the idea that the debate of climate change is a partisan issue.

I can only hope Sagan’s hopes are beginning to be realized.

Over the next few months, I will be reviewing at least two new books on climate change to supplement others that I have previously reviewed. I will be updating my Science Shelf news page as reviews are added to the site. If maintain an e-mail list of people who get regualr updates, and there are links to subscribe throughout the site.

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14 thoughts on “Has the climate change debate reached a tipping point?”

  1. I’d be tempted to agree about AGW not being political if it weren’t for the fact that the most political supporters of catastrophic AGW are not also very anti-nuclear power, which is a remarkably odd stance to have if you believe carbon pollution is on the verge of destroying civilization. Instead, we get a shell game on the nuclear power from them. We can have nuclear power, but not reprocessing. Without reprocessing there’s more nuclear waste, so we’re opposing nuclear power because it creates a lot of nuclear waste. Also, we’re going to heavily regulate it and then use the resulting long time for construction against it (rather than an argument to take action immediately?!) And also we’re going to concern ourselves with nuclear waste, while giving the seal of approval to CFCs with mercury and solar panels with toxic heavy metals. At least with nuclear waste, the stuff is 100% contained. We can’t say the same about solar panels. Or gasoline.

    There’s no push for iron fertilization either.

    Enron wanted cap and trade so it could profit off of it. Al “The center of the earth is a million degrees” Gore profits off the carbon credits he tries to sell. And the MSM consistently give a very biased reading of scientific data. Increased CO2, to a point, increases plant productivity by decreasing photorespiration. Fewer people are starving because of the increased CO2 in the atmosphere. A non-biased media would have reported that. But that would be off-message, wouldn’t it. So you don’t hear that. If the media is more intent on promoting a message than conveying the facts, then they can’t be relied upon for unbiased information.

    And now we’re seeing a deliberate and successful effort by AGW supporters to first criticize their opponents for not publishing in scientific journals and then working to shut down journals which publish papers critical to AGW. Criticizing methods is one thing. Preventing publication based on unfavorable results, however, is unscientific, and totally undermines the ‘science by consensus’ mantra of AGW supporters.

    Most significantly, the IPCC was willing to publish the “hockey stick” graph even though the supporting data wasn’t even publicly released. How is such a situation even ‘peer reviewable?’ If Mann doesn’t explain what his data was and how it was altered, how is that reproducable? And if it’s not reproducible, how can it, or any work which cites it, be called science?

  2. Your comment is reviving a blog entry from 15 months ago.

    The best book I’ve seen that puts the medieval warm period and the “Little Ice Age” in perspective, both scientifically and socio-politically, is “The Little Ice Age: How Climate Changed History” by Brian Fagan, reviewed at http://www.scienceshelf.com/LittleIceAge.htm

    As for the various issues raised by your link, the recent IPCC deliberations considered all of them and concluded that to a high level of probability, human activities, primarily the burning of fossil fuels, are the cause of the present warming episode.

    More recent entries in my blog (http://www.scienceblog.com/cms/blog/fred_bortz) discuss solar effects, including other than total insolation, on both Mars and Neptune.

    I also have a long discussion about persuading my conservative friend that global warming is not part of a liberal political agenda.

    As you will discover when reading those entries, I have a healthy appreciation for the views of skeptics, but I also have a healthy appreciation for the process that has led to the current scientific consensus.

    Politicians need to argue about what to do about global warming, but they need to start from a common scientific base. Too many of them are still busy attacking the scientists as either conspirators or dupes, because the science seems to be leading toward actions that will minimize the economic and political power of their political supporters, Big Oil and Big Coal.

    No matter what political strategy emerges, the scientific consensus tells us that we need to burn much less fossil fuel if we want to solve this problem. No wonder the fossil fuel interests attack both the scientists and their consensus.

    In any case, I invite your comments on my more recent blog entries.

    Fred Bortz
    Science and technology books for young readers (www.fredbortz.com)
    and Science book reviews (www.scienceshelf.com)

  3. Mars Melt Hints at Solar, Not Human, Cause for Warming, Scientist Says
    Kate Ravilious
    for National Geographic News

    February 28, 2007
    Simultaneous warming on Earth and Mars suggests that our planet’s recent climate changes have a natural—and not a human- induced—cause, according to one scientist’s controversial theory.

    (The rest of this entry has been removed as it is a duplicate of copyrighted material from the National Geographic site. Posters, please include excerpts plus a link to the original article, in such a case.)

  4. Your good at writing but you didn’t answer a single question I proposed. In fact I have attended presentations here in San Diego by scientists from Scripps and they weren’t able to answer those questions either. However, I noticed that you said humans are having an effect on the climate. What you didn’t say is that humans are the cause of global warming. Furthermore, you used the word “appears.” Does that mean your not absolutely sure, or is there a chance you might be wrong? If its true say it is, if it isn’t don’t imply it. The word “appears” is so subjective and over used and gives the impression your trying to cover your rear end. I have notice in jounal articles that scienetists will qualify there conclusions by using words like “appears” and “this may be the cause” or “further studies should be completed.” They are all starting to sound like lawyers. Just because there is a consensus about something doesn’t mean its true, the consensus could very well end up being wrong. By the way, a politician no matter if there from the right or left can’t interpt science very well. Both groups do a poor job and I can give you plenty of examples.

  5. These are precisely the kind of questions that good, skeptical scientists have been asking. Their research has led to a stronger and stronger consensus that human activities are having an effect, and it appears to be quite substantial. The debate, among scientists with perspectives such as yours (and mine) but far more expertise and in-depth knowledge of the research than we have, is now moving to a different level.

    Now they are asking if we may be on the verge of a tipping point in climate, and if so, what actions can we take to avoid it. (If human activity is moving us in one direction, the presumption is that the trend can be reversed by changes in our actions.) I’ll be reading new books on that issue soon, and you may wish to visit The Science Shelf and subscribe to receive alerts of new reviews, but the older books I’ve cited above and in another discussion on this blog will help you understand the current consensus and how it has been reached.

    To understand why so many well-intentioned people are still giving so much credence to the doubters, read The Republican War on Science by Chris Mooney. I approached that book as a skeptic, but I came out persuaded that science is indeed under ideological attack in the U.S. today. The word “Republican” in the title transforms what I see as an ideological fight into a partisan one. I’m still debating that angle, though for now the Democrats do seem to doing a better job of interpreting science in order to propose political policies.

    Fred Bortz — Science and technology books for young readers (www.fredbortz.com) and Science book reviews (www.scienceshelf.com)

  6. I have a 4 simple questions that I think have big implications. Even though they have yet to be answered with any great certainty we should demand the answers before jumping to conclusions.

    1. Since the Earth has been much warmer in the geologic past than it is now, shouldn’t we determine “definitively” what caused those warmer climates before we claim that the present warming trend is a result of only anthropogenic intervention?

    2. In other words could those same variables that created a warmer climates in the geologic past (prior to human existence) be responsible for the present warming trend?

    3. If not, can it be proven that those ancient variables are not responsible/contributing to the current warming trend?

    4. Have climatologists accounted for all possible variables for their current models, and if so how do they now they have?

    It seems to me there are a to many unanswered questions to blame humans for the current warming.

    I have no vested interest I only have a master of geological sciences degree and these questions have not be answered to any degree of certainty. By the way in the big realm of things considering the age of the Earth, 4.5 billion years, we have only had ice caps for a mere ~6 percent of that time. In otherwords its not normal in that perspective for the earth to have polar ice caps. So again how do we know that there are not other unaccountable variables at work causing the current warming trend along with possible human enhancement of the process?

  7. Scientific consensus is not determined by a poll but by a steady accumulation of data and by hypotheses that hold up to criticism. I suggest you look at the trajectory of the argument over the last twenty years. It went from numerous people speaking cautiously about what seemed to be hints of warming to an overwhelming collection of evidence that the average temperature was increasing.

    It went from most people saying that it wasn’t clear how much human activity was contributing to broad agreement that human activity was a significant component of the cause.

    Today, the argument is moving toward whether we are approaching a tipping point that could have catastrophic consequences. There is no consensus on that yet, but there is enough concern that policy makers ought to be paying attention.

    As far as consensus of a coming ice age in the 1970s, no. There was not enough evidence, though some hypotheses had more supporters than others. That’s a far cry from the consensus that we have today.

    As for oil, Hubbert’s theory of production peaks is holding up well. There was no consensus on when we would start to see economic problems, nor is there now. It’s not a question of whether we will use up a finite resource but when, and that involves human factors as well as geological ones. Most energy policy makers are weighing the best scientific data they have, but economic modeling is far less precise than resource modeling (which also has its limits). Many of them are legitimately concerned that we will see the end of the age of oil in the lifetime of today’s young adults. That’s not yet a consensus, but the hypothesis is quite credible at this point.

    As noted in my previous comment, I have a number of book reviews on my website about weather and climate. At the end of this message is a list of some of them. Even when these books suggest policy, they draw their conclusions from the evidence. Follow the above link to see the full list and to find links to my reviews.

    I’m planning to read two more books that lay out the science and its implications for the rest of this century. If you add yourself to my Science Shelf mailing list (links to subscribe on nearly every page), you’ll receive an alert when those reviews are published.

    I suggest you try The Change in the Weather from 1999 as a starting point, then read the newer titles. Then you will understand that a consensus is forming based on science.

    If you want to understand how ideology can get in the way, include The Republican War on Science on your reading list. Leave out the author’s partisanship and just look at the evidence for the ideological abuse of science by the people to whom we have entrusted our future.

    The steady drumbeat from people like that is a major reason why many decent people doubt that there is a consensus, probably including you. Remember, just because there are two sides to an issue does not mean that they are equally valid. Honest reporting requires discernment, not equal coverage of those who still claim the Earth is fhe center of the universe.

    Reading list:
    Climate Crash: Abrupt Climate Change and What It Means for Our Future by John D. Cox
    The Republican War on Science by Chris Mooney

    The Earth Policy Reader by Lester R. Brown
    Science, Money, and Politics: Political Triumph and Ethical Erosion by Daniel Greenberg
    State of the World 2003 by the Worldwatch Institute

    A Matter of Degrees: What Temperature Reveals About the Past and Future of Our Species, Planet, and Universe by Gino Segre

    The Coming Storm: Extreme Weather and Our Terrifying Future by Bob Reiss
    The Little Ice Age: How Climate Made History, 1300-1850 by Brian Fagan
    Our Final Hour: A Scientist’s Warning; How Terror, Error, and Environmental Disaster Threaten Humankind’s Future in This Century On Earth and Beyond by Martin Rees

    The Change in the Weather: People, Weather, and the Science of Climate by William K. Stevens

    Fred Bortz — Science and technology books for young readers (www.fredbortz.com) and Science book reviews (www.scienceshelf.com)

  8. How do we know there is a scientific consensus? Where is this poll? And where is the poll with scientists that disagree? I would like to see both before I accept either is a consensus.

    Was there not a scientific consensus in the 70’s that an ice age was coming? Or a consensus on the Population Bomb?

    Or that we would run out of oil by now?

    How does the below article change the global warming arguments?

    Seems to me they are admitting they do not understand the variables at all, and admit the data is sloppy at best. Take a good look at this article and what the scientists actually say. Eye opening!

    Plants Exhale Methane, Contribute to Warming, Study Says


  9. Thanks for your comment, which is provocative and ideological but respectful. I will answer in the same spirit.

    Sagan deliberately did not follow the criterion which is now often quoted, “Extraordinary claims, require extraordinary evidence.” But I wouldn’t go so far as to call Nuclear Winter a fraud.

    It was a worst case but plausible scenario that made people rethink their advocacy of the Mutually Assured Destruction theory of the arms race. It was an important factor, though hardly the only one, in the movement toward arms reduction treaties.

    Hansen and others speaking of the tipping point in climate change are careful to state that their worst case scenarios are not definite predictions but rather plausible outcomes with consequences too dire to be ignored.

    Some people on the left-wing side of this argument might agree with your statement that “Sagan sold out,” but they might view the sellout as giving credit to religion, as Billions and Billions does.

    You might also be interested in my comparative review of two Sagan biographies. Both of those discuss his reasons for promoting the Nuclear Winter hypothesis. He was the least important of the scientific contributors of the paper usually denoted as TTAPS for its five authors, but certainly the most active in promoting its conclusions.

    It has always puzzled me why religious conservatives have not spoken up about their concern for the planet. Could it be that they decided not to push the issue because it went against the interests of their big-business political allies on other social issues (abortion, gay marriage, etc.)? I’m glad they are finally speaking out on this. Preserving a viable planet is not a liberal or conservative issue. It is based on a scientific consensus that is no longer disputed except by those with vested interests in the status quo. (Though everyone denies vested interests.)

    Thanks again for opening this thread of discussion. I hope others will join in.

    Fred Bortz — Science and technology books for young readers (www.fredbortz.com) and Science book reviews (www.scienceshelf.com)

  10. It is ironic that you mentioned Carl Sagan in the context of politicized science. Sagan sold out in the mid-80’s becoming a major player in the whole nuclear winter fraud. In 1991 Gulf War, he returned to the theme appearing in many public forums pushing the idea that flaming Kuwaiti oil fields would create a “self-lofting” cloud that would overshadow most of Asia and possibly change the weather of the entire world.

    Sagan let fame go to his head. He became convinced that he had to use his scientific prestige to advance political causes. I think the same dynamic is driving the global warming “consensus”.

  11. … however stubbornly you stick to it :)

    That’s an ideological statement, which is why I added the “smiley.”

    But it is not ideological to respect a scientific consensus that has built up over decades. Some of the weather and climate books reviewed on my Science Shelf website have an ideological bent, but most focus on the evidence and the growing scientific consensus.

    Nonscientists who know how scientists build consensus now recognize that there may be huge problems ahead. Not acting can have serious consequences.

    In the religious realm that plays out this way: Many scientists and nonscientists espouse conservative religious faiths that place the stewardship of the planet as an important aspect of doing “God’s work.” Others, such as members of my liberal denomination, include “repairing the world” as one of their central good deeds. That repair is social as well as physical. The sentiment is not ideological, even when ideologues happen to hold it.

    If you’re having problems accepting the scientific consensus, I suggest that you click the link earlier in this reply and select reading material from the titles you think are least ideological.

    I’m afraid that you remain unconvinced because you wish things were different from the way they are. It’s almost “magical” thinking, and few things are more dangerous than relying on magic instead of acting on fact.

    Fred Bortz — Science and technology books for young readers (www.fredbortz.com) and Science book reviews (www.scienceshelf.com)

  12. “People who view this as a left-wing ideological issue” aren’t going to be swayed by a bunch of non-scientists jumping on the bandwagon. The reason we think it’s an ideological issue is because we’re not convinced by the scientific findings, not because we’re “right-wing” (although I am :-) ).

  13. Now you’re starting to sound ideological. You are misinterpreting scientists’ inherent caution not to overstate their conclusions as talking “like lawyers.”

    All data have inherent uncertainties and no one can be absolutely certain about their conclusions. However, there is a scientific consensus that represents the best understanding we have at this time. The consensus is growing stronger as the data, models, and computing power get better.

    The implications of the consensus are raising serious concerns. We can’t wait for a “smoking gun” before we act, because it will be too late at that point.

    I am not an expert, just well-read on the subject. I have directed you to a number of books that can help you to understand the way this scientific consensus has developed. It’s now up to you to do the hard work of absorbing the data and understanding the consensus. Neither the scientists at Scripps nor I can do that learning for you.

    It’s time for you to stop asking questions here and start reading. You need to understand both the process of science and the results. The answers to your questions are in the books I’ve recommended. How can I possibly describe all the details and the many examples in those books in this blog?

    This dialogue has run its course. Please do not reply. Just go read if you really want to understand.

    Fred Bortz — Science and technology books for young readers (www.fredbortz.com) and Science book reviews (www.scienceshelf.com)

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