Many carbon budgets are based on an under-estimation of warming to date, and the path of future warming. And all such budgets either ignore, or underplay, the loss of carbon from long-term stores — such as the melting of permafrost — which are already active processes.
This week, Prince Charles was the climate radical. Speaking by video link to Climate Week in New York, he said that the focus on 2050 climate targets “suggests we have room to delay” but, on the contrary, “it is absolutely vital, given the enormity of the problem we face, that we make truly transformative progress along the road to net zero by 2030”.
By contrast, when minister Angus Taylor launched his energy roadmap this week, Australia’s not-for-profit climate lobby’s main message was that “the Federal Government is behind the pack in its refusal to commit to a net-zero by 2050 emissions target”.
There was no talk about zero emissions by 2030, or in fact any 2030 goal, which appears to have become a threatened species. Advocates feared they would not be heard if they were “politically unrealistic”, but this is about science, too. And if you talk about 2050 just as most of the world is, you’ll be drowned out anyway, caught somewhere in the middle of the peloton, and certainly not up the front in the 2030 breakaway leaders’ group.
Australian groups that claim leadership on climate action are falling in line with big business lobby groups, mining companies and conservative and Labor state governments. BHP, RioTinto and Shell are all aboard the zero-2050 juggernaut now.
“Carbon budgets” for further greenhouse gas emissions are the bedrock of zero-2050 advocacy. These budgets, often associated with the IPCC and its 2018 special report on 1.5°C, are based on models which do not deal well with some climate elements, such as polar systems. This year Arctic sea-ice fell to the second lowest on record, and researchers say losing the reflective power of Arctic sea ice soon may advance the 2ºC threshold by 25 years.
Many carbon budgets are based on an under-estimation of warming to date, and the path of future warming. And all such budgets either ignore, or underplay, the loss of carbon from long-term stores — such as the melting of permafrost — which are already active processes.
All carbon budgets for 1.5°C, and most for 2°C, do not keep warming below those targets, but overshoot” for a decade or two or three by up to half a degree, before cooling to the target by 2100. That is achieved with huge amounts of bioenergy with carbon capture and storage, a proposed sequestration technology currently not working anywhere at scale other than in the existing oil and gas industry, which is only about storage of vented gases. This is classic moral hazard, and little more than an excuse to pollute now and wave a magic wand down the track.
All such budgets have monumentally unacceptable risks of exceeding the target, for example probabilities of 33% to 50%. That’s a one-in-two, or one-in-three, chance of failure, of charging past the 1.5°C or 2°C target to a hotter place. A carbon budget with a 50% chance of 2°C, for example, has a 10% chance of 4°C or more, which is not a good bet.
Would any climate lobby advocate get on board a plane if there were a one-in-three chance of crashing? Of course not, so why use that logic when the future of human civilisation and all those “special places” are at stake? In 2014, Mike Raupach, then head of CSIRO climate research in Canberra, produced work showing that to have a sensible — say 90% — chance of staying below 2°C, there was no carbon budget left.
There is no risk-management framework anywhere in the modern world — vaccine testing, construction, transport systems, or digital infrastructure — that would accept a 10% chance of failure, or one percent, or even a tenth of one percent.
It is not reasonable to advocate for risks that one would not gamble on in one’s own life.
There is also the equity issue, especially for those focused on climate justice. Let’s assume for a moment there Is a carbon budget for 2°C, even with bad risks. How should that be divided up between nations? There are three choices, the first is that big nations keep on polluting more per person because… well, because they are rich and claim a right to consume more that the other six billion people. That’s what zero-2050 advocacy in Australia assumes.
The second is that the budget be divided equally amongst every person on Earth. Do that, and it soon becomes clear that Australia, in the highest tier of per capita emitters, has no or little carbon budget left: we have already used up our share, or will do so within a handful of years. And the third option is to recognise the historic carbon debt of the rich countries, and allocate a greater per capita amount to low-polluting, developing nations; in this case the budget is long gone.
Scientists tell us that what we do right now, and in the next few years, is what really matters. The Emeritus Director of the Potsdam Institute, Prof. Hans Joachim Schellnhuber, warns that “climate change is now reaching the end-game, where very soon humanity must choose between taking unprecedented action, or accepting that it has been left too late and bear the consequences”.
Australia’s Prof. Will Steffen warns it is a big mistake to think we can “park” the Earth System at any given temperature rise – say 2°C – and expect it to stay there. He is the lead author of a research paper on a “Hothouse Earth” scenario, in which positive feedbacks and their mutual interaction drive the Earth System climate to a point of no return, whereby further warming would become self-sustaining, that is, without further human perturbations. This planetary threshold could exist at a temperature rise as low as 2°C, possibly even in the 1.5°C–2°C range.
Scientists say that the evidence from tipping points alone suggests that “we are in a state of planetary emergency: both the risk and urgency of the situation are acute… If damaging tipping cascades can occur and a global tipping point cannot be ruled out, then this is an existential threat to civilization”.
And they warn that we might already have lost control of whether tipping happens. That risk requires our immediate and undivided attention, because everything is at stake.
The short term matters most. Kicking the can down the road to 2050 is the wrong focus.