For the first time, I found a reference to the possibility of runaway climate change in an article in The Economist. Oddly enough, it is not in an article on climate change, but rather in a survey on water from last month:
Few people have dwelt on the worst possibility, even if it is highly unlikely to come about: that the extra water vapour held by a warmer atmosphere might set in train a runaway greenhouse effect in which temperatures rose ever faster and tipping-points for, say, the melting of ice sheets were reached. This possibility has received little consideration outside academia, perhaps because less improbable consequences of climate change provide enough to be gloomy about. The wise conclusion to be drawn may be that all planning should allow for greater uncertainty, and probably also greater variability, so every plan will need to have a greater degree of resilience built into it than in the past.
This account doesn’t even mention the most shocking possible form of runaway climate change, where the oceans boil away and the Earth becomes permanently uninhabitable for life as we know it.
I wonder how long it will be before the main opinion pieces in The Economist take this risk into consideration. So far, they seem to remain convinced that climate change is a rather secondary problem – certainly less important than maintaining global GDP growth – and that it will eventually be efficiently dealt with through carbon pricing schemes.
As I have said countless times before, the major risk with climate change is that the lags between emissions and effects will conceal just how gigantic a problem climate change could be until it has become too late to prevent the worst effects.
that the extra water vapour held by a warmer atmosphere might set in train a runaway greenhouse effect in which temperatures rose ever faster and tipping-points for, say, the melting of ice sheets were reached
Expressed this way, runaway climate change isn’t ‘highly unlikely to come about.’
Warming of the Earth allows the air to hold more water vapour which causes more warming. That is a basic feedback already built into climate models. Likewise, if emissions continue to rise, it is a business-as-normal scenario for temperatures to rise ever faster, and for tipping points to eventually be crossed.
“Greenhouse gases still warm planets, carbon dioxide is still a greenhouse gas and the amount of it in the Earth’s atmosphere is still shooting up. The temperature rose over the 20th century in a way that follows from these basic truths. Other mechanisms at play in the climate complicate the issue, but none of them offers a remotely satisfactory alternative explanation for the temperature rise. <a href="http://www.economist.com/node/16539392?story_id=16539392It is impossible to say with certainty how bad the 21st century’s heating will be, but there is a large chance of it getting hot enough to do harm, and a far from trivial chance of things turning catastrophic. This makes moving away from fossil fuels a global priority.
Yet the science of climate change has seemed to be derailed by climategate and the discovery of some errors in IPCC reports, even the gravest of which come far short of undermining its conclusions. Part of the explanation is no doubt a noxious campaign against the credibility of environmental science in general, and climate science in particular; the internet has allowed the doubt thus manufactured to go viral. But the problem also stems from the failings of climate scientists themselves, and the institutions they work in.”