Here’s the last in a series of three posts about shifting facts and climate change, from a talk in a series called Rights to a Green Future in Utrecht earlier this month. The general idea is that the facts of climate change are shifting around, and I think that’s doing something to moral reflection on action. The first post, about history and cumulative emissions, is here. The second, about the present state of play and equal per capital shares, is here. This post is about arguments for action that depend on some future good.
These arguments are hypothetical in form: if we value a sustainable world, a green future, a nice and habitable planet like the one we’ve got for those who come after us, then, the argument goes, such and such a sort of mitigation or adaptation strategy is now demanded. Sometimes the argument is reversed: if we want to avoid a future with a lot of miserable lives in it – suffering we might dodge if we choose wisely now – then, again, such and such a strategy is morally demanded of us.
Commitments to a sustainable future, when they do appear in international negotiations, typically mention the Brundtland Report’s definition: sustainability ‘implies meeting the needs of the present without compromising the ability of future generations to meet their own needs’. The question at the back of everyone’s mind when they hear this, the question which needs now to shift to the front, is this: is it possible for our needs and future needs to be met?
There are now a lot of people around – we were just joined by number 7 billion, and it looks like we’ll have 10 billion before the world’s population levels out. Most of our basic needs are met by burning fossil fuels. In other words, the moral argument for action now might be thought to boil down to the question of whether we really can act to meet everyone’s needs. In a nutshell, is sustainability possible? Is it possible to meet our own needs and leave a habitable world in our wake?
That’s partly an empirical question. The world seems to have settled on two kinds of targets or limits – the thought is that if we pass them we’re in for dangerous climate change and an unsustainable world. One is 2 degrees Celsius of warming above pre-industrial levels, and indeed this target was loudly endorsed at the United Nations Framework Convention on Climate Change conference in Cancun in 2010, which called for all countries to take urgent action to limit the increase in global average temperature to beneath this temperature threshold. (There’s a good summary here.) Some nations, particularly low lying island states with a lot to lose as sea levels rise, have argued that 1.5 degrees or less is the only safe maximum. (112 countries argue for this more ambitious target. There’s a list and details here, of the so called Least Developed Countries and the Association of Small Island States.)
How likely are we to stay under the 2 degree target? We have already warmed the world by .74 degrees, and another half a degree or so is thought to already be in the climate system. In a paper which appeared in October of this year, the examination of published emission scenarios from different climate models found that in the set of scenarios with a ‘likely’ chance of staying below 2 °C, and by that the mean merely a better than 66% chance, emissions must peak and begin falling rapidly very soon, between 2010 and 2020. (Joeri Rogelj et al, ‘Emission pathways consistent with a 2 °C global temperature limit’ Nature Climate Change, Volume: 1, (2011) 413–418)
As they put it,
“Without a firm commitment to put in place the mechanisms to enable an early global emissions peak followed by steep reductions thereafter, there are significant risks that the 2 °C target, endorsed by so many nations, is already slipping out of reach.”
The related target is 450 parts per million of greenhouse gasses in the atmosphere, which is thought to be the maximum we can emit and stay beneath the 2 degree threshold. The level at present is about 390 ppm. It turns out that while the projected date at which passing 450 is unavoidable is still several years ahead, the choices we make now about building power plants and extracting energy can ‘lock us in’ to pathways that overshoot 450. According to a report released last month by the International Energy Agency (World Energy Outlook 2011), the world’s existing infrastructure is already producing 80% of the carbon budget we’ve got left if we want to stay under 450 ppm. If trends continue and we build more fossil fuel burning energy plants, by 2015, 90% of the available “carbon budget” will spent. By 2017, the remaining carbon budget that might keep us under 450 ppm will be gone, and we’ll have no chance at all of staying under 2 degrees. As the Guardian reported,
“The door is closing,” Fatih Birol, chief economist at the International Energy Agency, said. “I am very worried – if we don’t change direction now on how we use energy, we will end up beyond what scientists tell us is the minimum [for safety] … If we do not have an international agreement, whose effect is put in place by 2017, then the door to [holding temperatures to 2C of warming] will be closed forever,” said Birol.
Are we likely to have such an agreement? Copenhagen was viewed by many as the world’s last chance at a global agreement, and of course that did not materialise. As I write this, newspaper reports from the current UN Climate Conference in Durban say that the world’s leading economies now privately admit that no new global climate agreement will be reached before 2016. The EU is pressing for targets now, but the US, Canada, Russia, Japan, India and China say new negotiations should not begin until 2015, to come into effect in 2020 at the earliest.
The IEA, again in its 2011 report,
“projects that world CO2 emissions from fuel combustion will continue to grow unabated, albeit at a lower rate … [this] is in line with the worst case scenario presented by the Intergovernmental Panel on Climate Change (IPCC) in the Fourth Assessment Report (2007), which projects a world average temperature increase of between 2.4°C and 6.4°C by 2100.”
For what it’s worth this kind of talk jives with the results of a 2009 poll, undertaken by the Guardian, which showed that,
“Almost nine out of 10 climate scientists do not believe political efforts to restrict global warming to 2C will succeed … An average rise of 4-5C by the end of this century is more likely, they say, given soaring carbon emissions and political constraints.”
What exactly does passing the 2 degree limit mean? No one is sure. It’s synonymous with so called ‘dangerous climate change’ or ‘runaway climate change’. The IPCC associate temperature rises above 2 degrees with ‘more and more negative impacts’. Mark Lynas put some flesh on the these conservative bones with a book called Six Degrees, an attempt to work out what we’re in for as the world heats up, degree by degree, by looking at what the world has been like, in its long history, at those temperatures. It’s just one take on our prospects past 2 degrees, but it’s well-researched, compelling stuff. Here’s a summary:
Between 2 and 3 degrees of warming, one ‘tipping point’ is crossed. Enough heat to cause the eventual complete melting of the Greenland ice sheet is in the system, which would eventually raise global sea levels by as much as seven metres and change the planet’s weather systems. Heat waves are likely to be responsible for many deaths each summer in Europe, coral reefs die and the marine food chain is disrupted, and the loss of fresh water from melting glaciers and snowpack affects both food production and the availability of drinking water.
Between 3 and 4 degrees, a large tipping point is crossed, where it’s thought that climate mechanisms might run out of control, with tipping points leading to the emission of more greenhouse gasses and more tipping points leading to the emission of still more greenhouse gasses, and so on until warming is, in effect, runaway. If the Amazon rainforest collapses, dries and burns, as is consistent with a 3 degree world, the carbon released could be enough to push us up another 1.5 degrees past a four degree world. Beyond three degrees, Africa, Australia and parts of North American turn into deserts on some climate models – food production obviously suffers, and water becomes scarce.
Between 4 and 5 degrees another tipping point is crossed, the Arctic permafrost melts, and huge amounts of methane and carbon dioxide are released into the atmosphere, further increasing the effects of climate change and pushing us up to 5 or 6 degrees. The Arctic melts, again increasing sea level. Humanity heads towards the poles, as other parts of the world become uninhabitable.
Beyond 5 degrees … there’s nothing like a clear picture. The world hasn’t been that hot for millions of years. Lynas talks of methane hydrates on the ocean floor erupting up in warmer waters and pushing the greenhouse effect out of control, and real questions arise here about the possibility of human beings joining the other 95% of the earth’s species in extinction. There’s talk of the Earth becoming a hot, desolate, lifeless ball, like Venus.
So what can we make of arguments for sustainability in the light of all this? Is sustainability still a live possibility? The argument is of the form, if we want a world like x, we must do y — but it’s possible that a world like x is becoming less and less likely.
It seems to me that sustainability arguments can take still take hold of us, with a particular sort of urgency, but perhaps only for a few years more, after which it becomes more and more likely that we’ll be unable to do anything to avoid the possibility of runaway climate change. I have to admit that it’s not easy to say things like this and keep a straight face. One sounds very much like some end-of-the-world cultist, warning that the end is nigh, but the voices telling us that we’ve only got a few years left to leave a habitable world in our wake are coming from the authors of peer reviewed papers, the heads of respected research institutions, the writers of books that win the Royal Society Science Prize. The world’s nations have agreed a 2 degree target, calling climate change an ‘urgent and potentially irreversible threat to human societies and the planet’. These aren’t crazy people talking. It’s the agreed language of representatives of our governments.
There are thoughts to be had here about civil disobedience, as well as other thoughts about human nature. But since I wrote this, we’ve had something of a conclusion in Durban. (Mark Lynas’ valuable discussion of the meaning of the Durban Platform is here.) It looks like there’s a commitment to have a commitment in 2015, which will come into legal force, if all hurdles are cleared, in 2020. Whether or not we’ve left it too late is unlcear, but there’s room for philosophical reflection on how to think about this possibility, about what it does to arguments for action on climate change, and about what to make of ourselves against this backdrop.