Part 2: Leaving fossil fuels in the ground: Who, how and when?
In previous blogs James Morrissey, with colleagues at Columbia University, made the case for considering equity in on debates around stranded assets, and for the need to focus efforts to strand coal. Here they argue that we need to act urgently if we are to avoid dangerous climate change.
This blog is part of a collaborative series by Oxfam and Columbia University. Read “Part 1: Leaving fossil fuels in the ground: Who, how, and when?” here, and the longer version of these posts on Columbia University’s website.
In previous blogs, Oxfam with colleagues at Columbia University, have highlighted the need to leave fossil fuels in the ground if we want to avoid dangerous climate change. This process, known as stranding assets, will require countries to forego significant revenues, which we have previously estimated to be worth tens of trillions dollars. For developing countries, who have contributed least to climate change, this is money that could be spent paying for important infrastructure like schools, clinics and roads. As a result, we’ve called for the need to have a broader conversation about equity when it comes to stranding fossil fuel assets. This has includes asking who and how we should strand them.
In addition to equity however, the challenge of stranding assets has an important time dimension.
The rapid rate at which we are currently emitting carbon dioxide (40 billion tons / year!) raises another question for stranded assets: how fast do we need to act to keep global temperature rise to a safe level?
We can explore this question using Graph 1 below. Here we plot the total potential CO2 released if we burned all the world’s fossil fuel reserves and compare it with carbon budgets for 1.5oC and 2oC (i.e. how much carbon we can safely burn while keeping global temperature rise within those specific amounts).
What is immediately clear is that there is far more CO2 contained in global reserves than can possibly be burned safely. What we still don’t know is how fast we need to move to ensure those fossil fuels stay in the ground. To answer that question we need to zoom in on the bottom right of the graph, and make some projections about the future.
Two future scenarios (the dotted lines) on Graph 2 are instructive. The first scenario (the straight line) assumes that we continue to emit CO2 at a constant rate, based on 2015 emissions. In this case we see that the 1.5oC budget runs out as early as 2025, while we only have until about 2035 before the 2oC budget runs out.
In the other scenario we (the curved line) we calculated the rates at which we would need to decrease emissions in order to get to 2050 without exhausting the carbon budget. It turns out that in order to maintain the 1.5oC budget, we will need to decrease emissions at around 8.5 percent annually. For 2oC the rate is around 3.5 percent. While these percentages might not sound very high, to get a sense of what they actually mean, consider that an 8.5 percent decrease in current emissions is the equivalent of pulling about 980 coal fired power stations off-line in one year! This will require and extra-ordinary level of ambition that is far greater than the efforts we are currently mustering.
Taken together, these calculations and those we’ve made previously, make a number of things clear. First, the issue of stranded assets involves complicated questions about equity and fairness. Given the huge implications for some of the world’s poorest countries, this is not a conversation that we can simply overlook. Second, the equity questions around stranded assets can be made more manageable if we make smart choices about which fossil fuels we use, and from this perspective we would do well to focus on immediately trying to strand coal. Third, although we need to consider equity in our discussions of stranded assets, concerns over equity should not get in the way of action on reducing emissions. As was shown above, our current rates of emissions are entirely unsustainable and we need to act immediately, and at scale, if we are going to stand any chance of keeping global temperature rise at safe levels.
EDITOR’S NOTE: The original, longer version of this blog can be found on the Columbia University website, and more details on the calculations supporting this blog can be found here.
 These are calculated at a 50% confidence for 1.5oC and 80% confidence for 2oC. The reason for the difference is that we have already gone beyond standing an 80% chance of remaining within 1.5oC. We use the most risk-averse percentages still available to us as published by Carbon Tracker.
 Note elsewhere this budget has been forecast as running out in just 5 years. The reason for this difference is that they are using a 66% confidence level for staying within 1.5oC, and likely using a less optimistic view on stabilizing emissions.