I've waited awhile to let the IPCC Fifth Assessment Report (AR5) hype die down a bit. Man, it sure was loud! But I'm not sure which was worse: the deniers saying that the report "proved" (huh?) that global warming has stopped or the enviros claiming that the report says "we face a global climate emergency" when it doesn't say that at all (but should).
Both groups are wrong. But for different reasons.
The deniers? Well, we've been pumping 90 million tons of CO2 into the atmosphere every DAY for ages (almost half of which has been absorbed by the oceans). Where do they think all the heat radiated by those extra greenhouse gas molecules has gone? (The answer, by the way, is that the oceans have been warmed and ice sheets and sea ice have been melted. It takes some heat to accomplish that!)
The enviro groups? Well, the mistake they've been making is not noticing how much the IPCC has left out — namely all positive (that is, amplifying) carbon and climate feedbacks. So the IPCC's new ("RCP") scenarios are actually underestimates of the dangers we are unleashing in the climate system. In other words, the situation is much worse, and much more urgent, than the IPCC's Working Group I (Physical Science Basis) report.
It's all very complicated and complex, and clearly the media have to simplify it for the public. But how can we rely on the IPCC's assessments when they don't include all possible sources of warming in their computer models (due to "carbon cycle uncertainties")? How can we trust the IPCC assessments when they offer a range, but then only speak to the "mean warming projections" (what they call "most likely")?
Should not climate scientists use the upper end of the temperature range when talking of risk? Especially since risk equals probability multiplied by magnitude (and the upper range of possible temperature increases is the potential magnitude)? Yet we're not just risking the mean warming projections, are we? We're also risking the upper ranges. And we're not just risking the upper ranges, we're risking those upper ranges with several degrees caused by carbon feedbacks tacked on.
Unfortunately (and perhaps ironically), the IPCC does not "do" risk. This intergovernmental panel that synthesizes the science of climate change has a code of silence on dangerous, disastrous, or catastrophic climate change. They claim that they cannot define "dangerous" climate change because that is a "value judgement" that science cannot make. (Gee, last time I checked, doctors were scientifically trained and they can tell you what's dangerous and deadly to human life.)
I'm not sure why the IPCC hobbles its scientific contributors and their discussions this way. But perhaps if each country's general public asked for more scientific honesty and a scientific assessment of how dangerous climate change could become, they'd be able to change their terms of reference.
If human beings (and our food/agriculture systems) have never experienced the temperatures that we're heading for, doesn't that at least imply danger ahead? Not "Ooh, it's not looking good," but "Holy flying %$#!, we're heading into a dangerous climate change emergency!"
Worth writing a letter or two, anyone? After all, changing political will is about the only transformative action (beyond individual reductions in carbon emissions) the public still has the power to take.
So, with apologies to the great Welsh bard, I'll leave you with a Dylan Thomas rendition by my husband that reminds us what our response to the AR5 ought to be.
Do not go gentle into this unnatural night.
Real people burn and rave at Mother Earth's deplorable plight.
Rage, rage against the dying of the light.
Rage, rage, rage with all your might.
— Peter Carter
p.s. That quote in the title is also from my hubby, someone who spends many, many hours every day reading and synthesizing research on climate change.