As my son (grade 4) has started a module at school on climate and global change, I thought I’d look into books on climate change for kids. Here’s what I have for them at the moment:

Weird Weather by Kate Evans. This is the kids favourite at the moment, probably because of its comicbook format. The narrative format works well – its involves the interplay between three characters: a businessman (playing the role of a denier), a scientist (who shows us the evidence) and a idealistic teenager, who gets increasingly frustrated that the businessman won’t listen.

The Down-to-Earth Guide to Global Warming, by Laurie David and Cambria Gordon. Visually very appealling, lots of interesting factoids for the kids, and a particular attention to the kinds of questions kids like to ask (e.g. to do with methane from cow farts).

How We Know What We Know About Our Changing Climate by Lynne Cherry and Gary Braasch. Beautiful book (fabulous photos!), mainly focusing on sources of evidence (ice cores, tree rings, etc), and how they were discovered. Really encourages the kids to do hands on data collection. Oh, and there’s a teacher’s guide as well, which I haven’t looked at yet.

Global Warming for Dummies by Elizabeth May and Zoe Caron. Just what we’d expect from a “Dummies Guide…” book. I bought it because I was on my way to a bookstore on April 1, when I heard an interview on the CBC with Elizabeth May (leader of the Canadian Green Party) talking about how they were planning to reduce the carbon footprint of their next election campaign, by hitchhiking all over Canada. My first reaction was incredulity, but then I remembered the date, and giggled uncontrollably all the way into the bookstore. So I just had to buy the book.

Whom do you believe: The Cato Institute, or the Hadley Centre? Both cannot be right. Yet both claim to be backed by real scientists.

First, to get this out of the way, the latest ad from Cato has been thoroughly debunked by RealClimate, including a critical look at whether the papers that Cato cites offer any support for Cato’s position (hint: they don’t), and a quick tour through related literature. So I won’t waste my time repeating their analysis.

The Cato folks attempted to answer back, but it’s largely by attacking red herrings. However, one point from this article jumped out at me:

“The fact that a scientist does not undertake original research on subject x does not have any bearing on whether that scientist can intelligently assess the scientific evidence forwarded in a debate on subject x”.

The thrust of this argument is an attempt to bury the idea of expertise, so that the opinions of the Cato institute’s miscellaneous collection of people with PhDs can somehow be equated with those of actual experts. Now, of course it is true that a (good) scientist in another field ought to be able to understand the basics of climate science, and know how to judge the quality of the research, the methods used, and the strength of the evidence, at least at some level. But unfortunately, real expertise requires a great deal of time and effort to acquire, no matter how smart you are.

If you want to publish in a field, you have to submit yourself to the peer-review process. The process is not perfect (incorrect results often do get published, and, on occasion, fabricated results too). But one thing it does do very well is to check whether authors are keeping up to date with the literature. That means that anyone who regularly publishes in good quality journals has to keep up to date with all the latest evidence. They cannot cherry pick.

Those who don’t publish in a particular field (either because they work in an unrelated field, or because they’re not active scientists at all) don’t have this obligation. Which means when they form opinions on a field other than their own, they are likely to be based on a very patchy reading of the field, and mixed up with a lot of personal preconceptions. They can cherry pick. Unfortunately, the more respected the scientist, the worse the problem. The most venerated (e.g. prize winners) enter a world in which so many people stroke their egos, they lose touch with the boundaries of their ignorance. I know this first hand, because some members of my own department have fallen into this trap: they allow their brilliance in one field to fool them into thinking they know a lot about other fields.

Hence, given two scientists who disagree with one another, it’s a useful rule of thumb to trust the one who is publishing regularly on the topic. More importantly, if there are thousands of scientists publishing regularly in a particular field and not one of them supports a particular statement about that field, you can be damn sure it’s wrong. Which is why the IPCC reviews of the literature are right, and Cato’s adverts are bullshit.

Disclaimer: I don’t publish in the climate science literature either (it’s not my field). I’ve spent enough time hanging out with climate scientists to have a good feel for the science, but I’ll also get it wrong occasionally. If in doubt, check with a real expert.

In our brainstorm session yesterday, someone (Faraz?) suggested I could kick off the ICSE session with a short video. The closest thing I can think of is this:

Wake Up, Freak Out – then Get a Grip

It’s not too long, it covers the recent science very well, and it is exactly the message I want to give – climate change is serious, urgent, demands massive systemic change, but is not something we should despair over. It also comes with a full transcript with detailed references into the primary scientific literature, which is well worth a browse.

Except that it scares the heck out of me every time I watch it. Could I really show this to an ICSE audience?

There is no silver bullet for climate change, just as there’s no silver bullet for software engineering. To understand why this is, you need to understand the magnitude of the problem.

Firstly, there’s the question of what a “safe” temperature rise would be. There’s a broad consensus among climate scientists that about a rise of around 2°C (above pre-industrial levels) is a sensible upper limit. I’ve asked a number of climate scientists why this threshold, and the answer is that above this level, scary feedback effects start to kick in, and then we’re in serious trouble. If you look at the assessments from the IPCC, the lowest stabilization level they consider is 450 ppm (parts per million), but its clear from their figures that even at this level, we would overshoot the 2°C threshold. Since that report, some scientists have argued this is way too high, and 350ppm would be a better target. Worryingly, the last IPCC assessment was based on climate models that did not include feedback effects.

Then, there’s the question of how to get there. Stabilizing at 350-450ppm requires a reduction of greenhouse emissions of around 80% in industrialized nations by the year 2050. Monbiot argues that if you think in terms of a reduction per capita, you have to allow for population growth. So that really means a reduction more like 90% per person. And again, due to our uncertainty about feedback effects, the emissions targets may need to be even lower.

How do reduce emissions by 90% per person? The problem is that our emissions of greenhouse gases come from everything we do, and no one activity or industry dominates. I was looking for a good graphic for my ICSE talk, to illustrate this point, when I came across this chart of sources of emissions:

 

World Greenhouse Gas Emissions by Sector

World Greenhouse Gas Emissions by Sector

 

 

I think that’s enough on it’s own to show there is not likely to be a silver bullet. The only way to solve the problem is a systemic analysis of sources of emissions, and we have to take into account a huge number of different options. If you want more detail on the figures, Jon Rynn at Grist has started to put together some spreadsheets to add up all the sources of emissions, and some specific contributors.

BTW, the IPCC’s frequently asked questions is a great primer for anyone new to the physics of climate change.

Over the last two years, evidence has accumulated that the IPCC reports released just two years ago underestimate the pace of climate change. Nature provides this summary. See also this article in Science Daily; and there are plenty more like it;

Emissions from fossil fuels growing faster than any of the scenarios included in the IPCC reports (news article ; original paper here). And recent studies indicate the effects are irreversible., at least for the next 1000 years.

Arctic Sea Ice, which is probably the most obvious “canary in the coal mine” is melting faster than the models predicted, and will likely never recover (Story from IPY here)

Greenland and Antarctic ice sheets melting 100 years ahead of schedule (news report; original papers here and here). Meanwhile new studies show the effect on the coastlines will be worse than previously thought, especially in North America and around the Indian Ocean (press release here; original paper here).

Sea level rise following the worst case scenario given in the IPCC reports (news report; original paper here and here).

Oceans soaking up less CO2, and hence losing their role as a carbon sink. (news report; original paper here

And finally some emerging evidence of massive methane releases as the permafrost melts (news report; no peer-reviewed paper yet).