Greg Craven teaches physics and chemistry at a Corvallis, Oregon, high school. In this book truth or falsity of climate change is secondary to risk analysis – whether to take significant action now or risk the consequences of little to no action now. This, his first book, is a must-read book for everyone!

Greg Craven admits he’s not a scientist. Rather his main qualification for proposing an informed “layman’s approach” to the risks of climate change is having borrowed the 30 brains in his classroom every period to mull questions of science and critical thinking for the last 20 years. He’s found that there’s no better way to refine a thought than to toss it out in front of a roomful of critical teenagers. Although my experience has been teaching college undergrad and grad students, I agree strongly with this last statement, for ‘us teachers’ know that we never learn a subject well or in depth until we have to teach it before critical students with open minds. Craven’s writing style is readily seen as fitting for discussing climate change risks before critical teenagers, but this style should not hinder most adults with open minds from following his risk analysis or from digesting his pro and con arguments. In the final chapter Greg Craven asks readers to set aside their inevitable biases so as to allow them to come up with their own conclusions of the risks involved in taking significant action now or promoting inaction now in regard to climate change and the future that we may force upon humanity by the risks we take now.

His chapter titles are informative, so I first list them [with brief comments in brackets]. After this I add additional comments on certain key aspects.

• Ch 0 - Should I Bother to Read This Book?; [two pages list 16 items, with “The Activists Shriek” page facing item-by-item “The Skeptics Appease” page, and also a 6-item chart in which only one item that says ‘No, don’t bother {reading it}’]
• Ch 1 - The Decision Grid: What’s the Worst That Could Happen; [his 2x2 grid has two rows – top row for GW (Global Warming) is False and bottom row for GW is True; left column is Significant Action Now and right column is Little to No Action Now; he walks you through this simple decision grid and aims to convince you that our important choice is to chose by column, not by row]
• Ch 2 - The Nature of Science: We Never Quite Know For Sure [for those who know not the nature of science]
• Ch 3 - Our Glitchy Brains: Have I Been a Fool? Oh, Let Me Count the Ways; [Confirmation bias is explained; scientists may speed-read Ch 2-3, but probably shouldn’t]
• Ch 4 - A Beautiful Rainbow of Credibility: The Credibility Spectrum; [this important chapter is crucial; credibility factors are expertise, bias, track record, and authority]
• Ch 5 - Gear Up: Mustering for the Expedition; [the tool kit (8 important tools) needed to make a rational decision and the source credibility needed]
• Ch 6 - A Whole Coop of Chicken Littles: Statements from Warmers; [20 sources for warmers and their credibility]
• Ch 7 - Everything’s Going to Be Just Fine: Statements from Skeptics; [30 sources for skeptics and their credibility; Ch 6-7 should be carefully read]
• Ch 8 - It’s Not the Temp That Gets Ya: Demystifying the Doomsday; [discusses climate science – greenhouse effect, carbon cycle, etc; a good summary with a simple bathtub analogy]
• Ch 9 - Author’s Conclusion: As If You Couldn’t Already Guess; [‘guess’ by comparing his well-reasoned credibility for the warmer and skeptic sources]
• Ch 10 - Reader’s Conclusion: Some Assembly Required; [this is where you use your own credibility sources to fill in ‘your’ decision grid and to then prepare yourself to defend it to those who have made different decision grids]

Craven's credibility spectrum has three groups. The high-credibility end has 'Statements from professional societies' and 'Statements from organizations that contradict their normal bias.' His “Big Fuzzy Middle” has, in decreasing order, 'University Research Programs,' 'Petitions,' and 'Think tanks and advocacy organizations.' His low-credibility end has, in decreasing order 'Individual Professionals' and 'Individual lay people.' I found his arguments for this credibility order to be close to mine and well-defended by Craven. I also found his choices in Ch 6 (warmers) and Ch 7 (skeptics) to mostly agree with mine. For the warmers' top end he has our NAS (National Academy of Sciences) first but also has ten other organizations, whereas for the skeptics' top end he could only find the luke-warm skepticism of the AAPG (American Association of Petroleum Geologists). For his low-end credibility for individual lay persons he lists only Al Gore for warmers but for skeptics he lists eight individuals, including Bjorn Lomborg and, lastly, OK's Senator James Inhofe. This is a small sample of his list, but it illustrates that his warmers list was top heavy in credibility whereas his skeptics list was quite bottom heavy. I could only find minor disagreements between his and my credibility 'heaviness factor.'

The Appendix explains the implications of the author’s choice that taking action now is the only wise bet. It begins with “You’re reading this appendix because your conclusion matches mine and you agree that we should swing into action to mitigate climate change by significantly reducing carbon emissions. So how do we make that happen? I’m no climate scientist, and I’m no policy analyst. I would make a mess of both. So I’m not going to discuss policy options here.” …”What we do is give the word go.” He then goes to those persons and/or groups to whom he has given very high credibility to present their ideas on climate science and, most importantly, the actions suggested for his column choice. He found (as did I) that the worse column of the decision grid was the right column (Little to No Action Now) because the lower-right square of the 2x2 grid – that is, ‘GW is true’ and we decided to take ‘little to no action now’ – led to the very worse consequences, which he listed under the header Global Catastrophe with subheadings of very bad economic, political, social, public health, and environmental results. In comparison to this very bad ‘catastrophe’ square, the other bad square is the top-left one – that is, ‘GW is false’ but we took ‘significant action now’. (The other two squares – top-right: ‘GW is false’ and we took ‘little to no action now’ and bottom-left: ‘GW is true’ and we took ‘significant action now’ are almost non-contenders in making a wise bet on what column decision to take, so I say no more about them. In summary, the only wise choice is clearly the first column - to take 'Significant Action Now'.

It needs to be emphasized again that the type of risk we need to take is the column decision on whether we should take action now or not. Craven earlier made a very convincing argument that a row decision – whether GW is true or false – is not the crucial decision that we face now. Time and further climate data – that is, the science – will decide the extent to which GW is true or false. That is out of our control today, despite all recent data pointing towards GW is true (data which has convinced me that GW is real), since all climate change models are oversimplified, they are at best approximate guides to our planet’s future. But, as Craven makes clear over and over, the action we take, or fail to take, is under our control. I feel strongly that this book, despite its ‘high-school’ style and organization, is a must read for everyone today, especially for those who feel that the truth or falsity of GW must be more firmly established before any significant action is taken. They must realize that they are advocating a great risk that is very unwise for humanity’s future, as well as that of other life forms. The title of Greg Craven’s book is the only rational and wise response to the climate change debate. I therefore give it my very highest recommendation. Think six stars (at least)!