What’s the worst that could happen?

What's the Worst That Could Happen?: Cutting Through the Hubbub Over Global Warming

Greg Craven has been a YouTube phenomenon. Seven million people have viewed his short climate change video posted in 2007, The Most Terrifying Video You’ll Ever See. It was followed up with a number of others. Now he’s produced a lively and engaging book What’s The Worst That Could Happen?  A Rational Response to the Climate Change Debate which may not reach quite as many people, but certainly deserves a wide readership.

Craven is a high school science teacher in Oregon. He is open about the deep alarm he feels about climate change. But he’s not a climate scientist. He doesn’t set out to convince  readers of the reality of global warming. Instead he offers what he calls some thinking tools, not for working out whether climate change is true or not, but for working out whether we should be taking action or not. The decision grid “allows you to stop focusing on who’s right and instead ask, what’s the wisest thing to do, given the risks and consequences?“ Risk management, he calls it. The grid is a simple 2×2 affair, which compares and considers the consequences of action or inaction if global warming turns out to be either true or false. He’s aware that when he talks about a debate between “warmers” and “sceptics” he’s describing popular perception, not what goes on in climate science circles, but popular perception is what he is concerned to address.

The book was honed in the classroom. He found there’s no better way to refine a thought than to toss it out in front of a roomful of critical teenagers. The writing is crisp, quirky, often humorous, never ponderous. An active reader is presupposed, with pages set aside for participatory jottings. It’s hard to avoid engagement. Yet there’s an unmistakable drive and underlying seriousness to the vigorous text.

Craven offers useful observations about how science works, as a preliminary to embarking on the decision quest. Some examples: science is about pursuing the truth, but it never claims to actually get there. Its statements are usually very conservative. The presence of differing views doesn’t mean that something is controversial. Peer-reviewed papers are the basic currency of science. Science often runs counter to common sense, which would still have us thinking the sun goes round the earth.

The next preliminary step is to examine the ways our brains work (defectively). Confirmation bias is the main problem for us to be alert to, and he provides many suggestions as to how to manage that. Another feature important in the global warming debate is that the human brain’s alarm system has been conditioned over time to respond to threats that are immediate and visible.

Then it’s on to a tool he developed himself, the credibility spectrum. This is a ranking of sources by such factors as expertise, bias, track record, authority within the scientific community, reputation. Readers are invited to make up their own spectrum, but Craven shares his, which puts statements from professional societies at the top, along with statements from organizations that contradict their normal bias. Next down are government reports. In the middle come university research programmes, appropriately sourced petitions, think tanks and advocacy organisations. Down then to individual professionals, book writers, and finally individual lay people.  He chooses and identifies sources for each of those categories from both sides, warmers and sceptics.

There follows an excellent 30-page summary of what it is that the warmers are saying we should be concerned about and the doomsday they see ahead if we carry on as we are. The point of this chapter is simply to establish that their concern is not unreasonable and warrants at least the amount of attention needed to decide whether we should do anything about it or not. But the striking clarity of his account gives the chapter an importance well beyond that limited intention.

He then returns to his own credibility spectrum, warmers to the left, sceptics to the right, and explains why it could only lead him to the conclusion it did:

“When I look at the stunningly strident statements from all those calm professional sources at the top left, and I think, What are the chances they’re all out to lunch? and then I add my observations that the predictions have only been getting more dire and more immediate as time goes on, it scares the willies out of me. So I vote for slamming on the brakes. Hard. I can recover from any hot coffee that I spill on my lap.  But I can’t put myself and my car back together again if I drive confidently off a cliff, kids in the back.”

After that he sends his readers off with step by step instructions to build their own credibility spectrum and use the decision grid to produce their own conclusion.

For those readers who come to the same conclusion as he does, the appendix offers a strong recommendation. Craven stands with Hansen, because he has the best track record for predictions which mainstream science eventually catches up with. 350 ppm has to be the target for CO2 concentration in the atmosphere. This will require an effort similar to that which the US put into World War II when massive government action accomplished the seemingly impossible in an amazingly short passage of time. In perhaps the greatest economic mobilisation in the history of the world people invested an average of 25 percent of household income in War Bonds. And far from dooming the economy the collected effort of the citizenry brought the US out of the Great Depression and produced the world’s strongest economy.

Personal action to reduce our carbon footprint is fine, but it won’t get us to where we need to be. Only government action can do that. We need a collective determination, and the most significant contribution the individual can make is to spread the word, activate the interconnected web of communication that permeates our society.  Go viral. “Focus on burning the number 350 into the collective consciousness.” Over to the reader.

This is a most welcome book. It has proved astonishingly difficult for the findings of climate science to be communicated to the public. In part this is due to the success of the organised denialist campaign, in part to the cautious language of science itself, in part to the difficulty of comprehending how our apparently secure world can possibly be under the threat of such an enormous peril. Craven doesn’t try to fill the comprehension gap with information –- though what information he does provide along the way is mainstream and persuasive –- but invites his readers to give serious scientists the attention and respect their work demands. And he tries to do it not by telling, but by showing how they can get to the position where they find their own realisation that the science must be heeded.

15 thoughts on “What’s the worst that could happen?”

  1. The 2×2 grid is a useful way of thinking about it, but it does require a bit of honesty in how you characterise the costs and benefits. If you take Roger’s approach, and say that the only “cost” of increased CO2 will be greater crop productivity, then you are never going to get the right answer. Equally, the warmists need to be realistic about the costs of mitigation/prevention (the true answer lies somewhere in the middle of “free” and “destruction of the world economy”).

    If you do that, it’s easy to see that any cost short of “destruction of the world economy” is worth it, even if AGW turns out to be false. The key driver is peak oil, and the fact that sooner or later we are going to have to switch to a zero-carbon economy anyway. The longer we leave that, the more it will cost, so that the “do nothing” side of the grid ends up costing at least as much as the “do something” side whether AGW is true or not. The worst possible quadrant to choose is “AGW is real/do nothing”, which pretty much guarantees the end of human civilization.

    The only logical thing to do now is to act as if AGW is real.

    1. That comment is a bit hard to follow.

      But… Peak oil is a whole other argument, its not a reason to reduce ’emissions’, but a reason to reduce oil use. For example, if peak oil was the problem, is there anything wrong with building coal fired power stations? Or raising cattle?

      1. What are we going to use to power cars once oil becomes uneconomical?

        Which do you think is more likely, steam powered cars or electric cars? Either way, all this would do is increase our consumption of coal, and bring on peak coal, in which case we still need to find alternate power sources.

        The carbon economy will not last forever. It’s merely a question of how long we have to find alternate power sources.

  2. He says no one can point out a flaw, so I’ll give it a go cause I see a major one.

    The diagram is a simple Nash Equilibrium. However it is of course dependent, like CTG said on what you put in the boxes, also the percentages you put on the rows, but also another factor not mentioned, and that is the time horizon. This Greg Craven seems to assume the decision we make now we are stuck with for 100 years. What if the time horizon is limited to commitment period two? ie assume our actions until 2013 are locked in as part of Kyoto and we are looking to lock in a decision for the period 2013-2020 at Copenhagen (and also assume CP2 is 8 years, which is unlikely).

    What kind of picture will this give? Lets avoid the assumptions around magnitude and look at four outcomes rather than 2. The assumptions around probability still exist.

    If climate change is real and we do nothing now to stop it, what will happen in the future? If in ten years temperatures are another 0.2C warmer, what will the ten year delay cause compared to cautious action now?

    Aggressive action in ten years once the cause is obvious versus cautious action today? Not the end of the world as Greg concludes. Perhaps we increase the costs of mitigation.

    However if we take cautious action today, ie agree to cuts of 5-10% from BAU in Copenhagen, and then temperatures stay the same or fall for the next ten years, and people decide that maybe it was a non-crisis, what is the cost? Well to be fair it is not huge either – perhaps 0.5-2% of GDP (so not small).

    Another option is to take aggressive action now – 20-40% reductions in the developed world by 2020. What will this cost? For NZ? Given we are already at +24%, and half our emissions are export focused, I would say a lot. Defiantly a depression in New Zealand. Perhaps worldwide.

    After looking at three options, there is one more. What is the worst case scenario for 2020? Gareth can tell me, but given the worst case for 2100 is +6C, and we are currently +0.6C, I’ll guess its around +1C. What does this look like? +0.4C in a decade? Drought? Hurricanes? But still within the +2C considered dangerous. It would be a wake up call, and then the world would likely take climate change seriously. So there would be a cost of delay of action, but this, worst case scenario, would not be the “end of the world as we know it”.

    So our choices that look acceptable for the time period 2013-2020 to me are cautious action or no action.

    Is this a flaw in his diagram?

    1. Ignoring NZ for the moment, it makes no sense whatsoever to delay action any longer. Even if all man-made CO2 emissions stopped overnight, we would still be facing a few more decades of warming, due to latent heat in the oceans. This will induce further warming in the Arctic, which will lead to more ice loss and positive feedbacks from lower albedo, not to mention the continuing outgassing of methane deposits which will also add a positive feedback. There will almost certainly be some geo-engineering required to actively reduce CO2 back to 350ppm or less, in order to counteract the warming still in store (and also to reduce ocean acidification).

      You can’t just say that BAU will have no effect over the short term, therefore we don’t need to do anything in the short term.

      As to whether we in NZ need to do anything, either in the short term or the long term, I guess it depends on whether you want NZ to have an economy or not. If we do nothing, the rest of the world will tax us to buggery regardless of how small we are.

      You only ever look at costs, as if the only way that governments can reduce emissions is by buying their way out. You need to look at it as a transformational process. There have been plenty of cases in history where an economy has been radically transformed without inducing recession/depression – the US economy in WW2 expanded greatly, despite the huge costs of the transformation.

  3. R2D2, Craven recommends the diagram as a means for each reader to reach a decision about the most sensible response to the risks and consequences. He fills his own in after using his credibility spectrum to assess the risks. The reason that you see little cause for action now is that you are giving credibility to different scientific sources from those which he finds persuasive. At the top of his list are the National Academy of Sciences, the American Association for the Advancement of Science, the National Research Council, the National Intelligence Assessment, the Pentagon, the Centre for Naval Analyses, and many others before he even gets to the IPCC and the Stern Review, with James Hansen down the bottom as an individual scientist. I don’t know what your credibility spectrum looks like, but I presume it manages to exclude all of these sources. Your picture of nothing more thana slow gradual temperature rise which we could put a stop to at any stage we decided doesn’t allow for the latent rise already built into the system, nor for the feedbacks or abrupt changes which the scientists warn us will be part of the dangerous process which we have initiated. In other words, their picture is much more alarming than the one you appear to be working with. Just how alarming has yet to dawn on many of our leaders. You’ve still got plenty of company.

    PS. After posting this comment I realised CTG had posted before me. I would have endorsed the examples of latency and feedbacks he provides.

  4. R2D2 – the time dependence of the solution is probably worse than you posit. If the scientific case for CO2 reduction is anything like we are hearing (ie reducing atm. CO2 to 350ppm by later this century) then we are already in for a herculean task. If you put the decision off for another 10 years then the required rates of rebuilding infrastructure (not to mention extracting the already emitted CO2) become impossibly large.

    So I don’t think that (given our current state of scientific knowledge) that it is a feasible option to say “we can decide in 10 years time”. That is a gamble on the current scientific understanding being wrong by a large margin. Or maybe saying that we don’t care – we can always build bigger sea walls.

  5. I think you guys all missed the point I was making and focused on the part of the post that said “However if..temperatures stay the same or fall”.

    I haven’t read Craven’s book Bryan, but I did watch his you tube vid and he actually says we set aside the debate “by acknowledging that no one can no with absolute certainty what the physical world will do”.

    I have done this in my model by allowing for 3 different climate possibilities.

    My point is he assumes that the decision we make now is locked in forever. I am saying the decision we make now is locked in until 2020 at the latest. Therefore we should look at the options he outlines in his matrix with the assumption that we can change track once the science is clear (and don’t say it is clear now! we are setting that aside!).

    CTG: You say there is no sense in waiting, and then acknowledge the option of geo-engineering – geo-engineering will allow the option of catching up later. You also speak in absolute certainty the worst case IPCC projections are correct when the assumption is no one can know.

    I never said BAU as usual will have no effect over the short term (although I believe this I did not argue it as certain). I said the end of world scenario he pictures will not eventuate by 2020. The difference between action now and action in 2020 is not the end of the world – therefore I have found a flaw in his model.

    If you have an IPCC projection that says BAU until 2020 will result in irreversible climate change, but the 15% reduction currently being proposed for developing nations (and BAU for the rest of the world) will result in ‘crisis averted’ please post the link.

    1. You are still missing the point.

      It is not the rate at which we pump CO2 into the atmosphere that matters, it is the total volume of CO2 that has been released that matters. If we want to keep under a 2°C increase (which I think will still be too much), then that works out at about 570 Gton of CO2 – of which we have already released about 300 Gton, so we have about 250
      odd Gton that we can safely burn and still (probably) be under the 2°C limit.

      If we were to follow BAU to 2100, the estimated total release would be 1600 Gton, so I would estimate that we have maybe 20 years left at BAU burn rates before we have burnt all the fossil fuels we can ever safely burn. Ever.

      If we follow your suggestion, and wait 10 years before we even start doing anything about it, that leaves us with maybe 10 years to fix the problem.

      I would far rather have 20 years to try and fix the problem than 10, so as far as I am concerned, we need to start making drastic reductions right now. Well, actually we needed to start making those reductions 20 years ago, when the scientists first told us we needed to.

      Oh, and as far as geo-engineering goes, there is currently no feasible idea for actually reducing CO2 in the atmosphere (other than planting lots and lots and lots of trees), so we can’t really pin our hopes on that. My point was that if we keep sending CO2 up, we are going to have to bring it down somehow – and we don’t know how.

      1. Woa OK, take a step back, my post was about a decision matrix proposed by Craven. In that matrix the author says we have two choices, do nothing, or do lots. He says there are two possible consequences, one is that the atmosphere will warm with CO2 and one is that the atmosphere will not. So there are in total 4 different outcomes.

        In the ‘do nothing, IPCC was right’ outcome he paints a picture of ‘the end of the world as we know it’. From this I presume he talking to situation between 2050-2100, although he does not state a date.

        So far everything I have stated in this post is indisputable.

        My proposition is that we do not have to follow the choice we make now forever, as I thought he was implying in his diagram. Do you disagree with this? Do you have projections that show only dramatic reductions in the next ten years will avert climate change? If this is true I would say as the world stumbles towards Copenhagen and a deal is not likely until sometime in 2010 or 11 we have missed the boat.

        My suggestion was not ‘wait ten years’, I said, “So our choices that look acceptable for the time period 2013-2020 to me are cautious action or no action.”

        It appears your preference is drastic action now.

        OK, lets run with this, this is one of the options I outlined in my decision matrix.

        Currently Annex-1 nations are proposing to cut by about 15% from 1990 levels for commitment period 2. Non Annex-1 nations (>60% of emissions) have not yet agreed to any nationally appropriate mitigation commitments. This is not drastic so I suggest this situation is probably considered ‘cautious action’.

        Your proposal for dramatic action, what would that look like then? Keeping in mind “no one can know for certain how the physical world will react”, and that Craven has said we should choose the option that avoids the worst outcome, what is worse, your version of the cuts necessary in a reality where AGW is not real, or BAU for ten years in a world where AGW is real?

        Also keep in mind I suggested cautious action avoided the worst outcomes. I am only following Craven’s logic.

        1. Now you are getting somewhere.

          Indeed, the choice is between ‘do nothing’ and ‘do lots’. Your option of ‘do a little now, and then lots more only when we really know that something is happening’ is really the same thing as ‘do nothing’.

          “BAU for ten years in a world where AGW is real” is definitely the worst option, because that will almost certainly commit us to more than 2°C warming by the end of the century whatever we do from that point on. Our only option then will be adaptation and geo-engineering to try and reduce the effects – and that would be massively expensive.

          Yes, I agree that what most countries – NZ included – have put on the table for Copenhagen is not enough.

          Like I said before, drastic action does not mean “take out the chequebook and write a cheque with lots of zeros on the end”. We have maybe 20 years to replace fossil fuels, which ought to be enough as long as everyone pulls together.

        2. A question for you, R2: how much evidence of warming would you need to convince you personally that there is a problem?

          I first heard about global warming when I was at uni, in 1989 or thereabouts. Even at that time, the scientific evidence was pretty clear that CO2 was responsible for most of the warming, and there would be a big problem if CO2 emissions were not reduced.

          Looking at the GISS data, the mean global temperature anomaly for the 11 years centred on 1989 was 0.28°C.

          The mean global temperature anomaly for the 11 years centred on 2004 (the last 11 year period we have full year data for) is 0.60°C. So temperatures have risen 0.32°C from the time that scientists first began to say that we should cut CO2 emissions. That is 0.2°C per decade, well on course for +2°C by 2100.

          How much more does it need to rise, R2?

    2. The difference between action now and action in 2020 is not the end of the world.

      It very well might be. Your approach ignores two things. The first is the climate commitment — the inevitable warming after atmospheric GHG levels stabilise. Delaying action now means accepting worse damage later. As Bryan says below, this is pushing the problem onto future generations, and making the problem they will face much worse than it need be.

      The second issue is that by delaying action you make the eventual action required much more drastic, and therefore much more expensive.

      We’ve got a very good idea where we need to be headed (350ppm), and we need to get going as soon as possible. See also yesterdays post on planeary boundaries.

  6. R2D2
    “Therefore we should look at the options he outlines in his matrix with the assumption that we can change track once the science is clear (and don’t say it is clear now! we are setting that aside!).”

    But indeed the science is clear now. It says we are in grave danger of possibly catastrophic consequences if we continue raising the level of atmospheric greenhouse gases. We will only know whether that is true or not by allowing it to happen. Craven is asking whether that is a risk his readers feel like taking. He doesn’t. You evidently do. To my mind that puts you in the category of either the ignorant or the reckless, neither of whom I want in charge of my grandchildren’s future or the future of wider humanity.

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