Bob Ward: It is important to recognise what has been achieved through the international negotiations. Over the past year, more than 150 Parties to the UNFCCC, representing almost 90 per cent of annual global emissions of greenhouse gases, have submitted Intended Nationally Determined Contributions. These have included pledges, for the first time, to limit or reduce their emissions beyond 2020. Collectively these represent a significant improvement on ‘business as usual’ emissions in 2030, but they are not yet consistent with a pathway that stands a reasonable chance of avoiding global warming of more than 2°C. That is why countries have already acknowledged that the summit in Paris later this year is not a one-off, but the start of a process through which ambitions to reduce emissions will be ramped up towards the goal of avoiding dangerous climate change.
AE: The start of a process to reduce emissions? We’re almost a quarter of a century in to this process! You write as if we have all the time in the world – when instead we’re in the last chance saloon for limiting average warming to 2°C. Since you haven’t replied to my point that we won’t stabilise greenhouse gas concentrations unless and until we have a global emissions budget covering all countries, let me put the question to you: how do you imagine that the incremental approach you advocate will control global warming? Or will you at least be honest enough to admit that it can’t? The best thing the UK ever did on this issue was to pass the 2008 Climate Change Act, which put a legally binding requirement on future governments to keep Britain’s emissions within a safe, scientifically-based national emissions budget. It was an approach based on the clear sense that some issues are too important to be left to the vagaries of short-term political cycles, and need policy designed to manage the problem all the way until it’s solved. If such an approach makes sense at national level – and it does – then it’s doubly essential at global level. So, again: why aren’t you pushing for this in Paris?
BW: You are quite right that countries need to do more, but you have not provided a practical way to achieve this. You seem to think that countries can be forced to do more than they want. How? The first phase of the Kyoto Protocol attempted to force countries to comply with national targets. But countries, like the United States, that did not want to honour their commitments, simply withdrew. In addition, there is no way of assigning national emissions targets at present, because there is no agreement about what a fair target is for each country. The Conference of the Parties to the UNFCCC is a negotiation process between more than 190 nations. It is messy, frustrating and slow. But it is also the only way we currently have of promoting collective and coordinated action against climate change by all countries around the world.
AE: Milton Friedman famously observed that only a crisis produces real change, and that the crucial thing is to have the right ideas lying around ready for those moments. What my colleagues and I are proposing is just such an idea. What’s yours? I do agree with you that the question of fairness is right at the heart of this issue. But here too, I’m unclear what approach you’re suggesting. True, there’s no obvious, intuitively fair approach if the challenge is couched in terms of burden-sharing. But once we frame it as how to share out a global emissions budget then the opposite becomes true. After all, there’s no shared commons more basic than the sky. How are we going to share it out – which, again, we have to if we want to solve climate change – other than on the basis of equal per capita shares for all? This approach is effective, fair, affordable, and above all necessary. I don’t disagree with you that we’re dealing with an issue of awesome difficulty – or pretend that countries are actually ready yet to solve climate change. But surely it’s our job as experts to make clear what the solution looks like once they are?
BW: The main weakness of the United Nations negotiation process has been that it has framed action against climate change as a burden-sharing problem. This blinkered view creates a perverse incentive for countries to minimise their efforts. However, there are clear signs since the summit in Copenhagen in 2009 that countries increasingly recognise the broader economic benefits that climate change policies deliver. In particular there is a realisation that reducing the consumption of coal will not only reduce greenhouse gas emissions but also the local air pollution that kills millions of people across the world each year. This should mean that beyond Paris, countries will start to ramp up their ambition based on the realisation of multiple opportunities offered by a low-carbon economy, instead of remaining trapped in a zero-sum game of burden-sharing. More countries now understand that low-carbon economic growth and development is the only sustainable path to greater prosperity and well-being.
AE: I agree with you about the technological opportunities of a low-carbon economy. The key question is what it will take to drive that shift – given that today, prices don’t tell the ‘truth’ about environmental impacts like greenhouse gas emissions (which are ‘externalised’ from prices, as economists would put it). One option, of course, is for countries to undertake decarbonisation domestically, through regulation, subsidies, carbon taxes and so on. But one of our key findings from SkyShares is how inefficient and expensive that is, compared to an international approach that includes emissions trading. In our Reference Scenario, we find that total decarbonisation costs for the world in 2030 come to 0.52 per cent of global GDP if emissions trading is allowed – but over six times that, at 3.38 per cent of global GDP, if trading isn’t permitted. Trading saves everyone money – and also creates the massive new flows of development finance to poor countries that I mentioned earlier. But we only unlock these benefits if we grasp the nettle of agreeing and allocating a global emissions budget.
BW: I agree that a greater degree of cooperation among countries would speed up the pace of decarbonisation and reduce its costs. A global uniform price on carbon is a fundamental mechanism to help drive the transition to a low-carbon economy. But we should recognise that different countries are starting the transition from different starting points and have different domestic circumstances to take into account. Even if we do not achieve an economically optimal transition, it will still be far less costly than continuing along a high-carbon path. The outcome from Paris should signal the intention of all governments to collectively manage the risks of climate change, including through increased collaboration. This will build confidence among policy-makers, as well as among investors, businesses and the public, about where the world is headed, allowing each country to accelerate its transition to a low-carbon future.