Overshoot should mark the end of the road for supposed 'policy relevance'

Overshoot is official. This week the United Nations Environment Programme published the report Limiting Overshoot, in which it says global warming will exceed 1.5°C within the next few year. UNEP argues that the priority now

must be to keep the exceedance and peak in warming as short-lived and as low as possible, while working toward bringing temperatures back down thereafter. This is not the preferred path, says the report, but it’s the one we’re on and need to prepare for.

Much of the report is excellent. As usual it comes with fantastic design and hammers some key messages such as carbon dioxide removal is not a substitute for emissions cuts now. But ultimately it’s another missed opportunity .

For example, the report does not say how we have ended up here. It doesn’t say banks such as  JP Morgan have facilitated hundreds of billions of dollars of funding for new oil and gas projects; that oil and gas companies such as Shell and BP have rolled back even the most feeble attempts to diversity away from fossil fuels; how politicians continue to cravenly act to further fossil fuel interests. Instead its treats the continuing surge of greenhouse gas emissions almost as a natural force. It argues that we must implement strong mitigation policies, while never mentioning why actually effective mitigation is still incredibly difficult to achieve. That means it has very little to say about how are we going to dramatically bend the curve of emissions, let alone transformative adaptation. 

The reason for such omissions is because UNEP, along with much of climate change academia, chooses to be ‘policy relevant, not policy prescriptive’. It’s not for them to say what society should do. Rather, their role is to provide politicians – with all their limitations, constraints, conflicts and corruption – with analysis that is relevant to their limited, constrained, conflicted, and corrupted activities. And so we got net zero with promises that rapid changes to aviation, cement production and steel making are not necessary because we will use carbon dioxide removal to offset these so-called hard to abate sectors. Now with the wider acknowledgment that 1.5°C is immanent, UNEP extends this approach into overshoot where we will offset decades of climate policy failures with gigaton-scale carbon dioxide removal in the future. To be clear about this, nothing here is new. The 2015 Paris Agreement effectively baked in overshoot with its end of century temperature targets and framing of the climate crisis as an issue of sources and sinks of carbon dioxide. So it set the stage for overshoot and a recovery.

Unfortunately, UNEP recycles this crap. There are no credible plans to implement the required amounts of carbon removal to get temperatures back to 1.5°C this century. In fairness to the report, it does acknowledge that decline above 1.8°C (an amount of warming that seems certain) back to 1.5°C by 2100 would be ‘increasingly challenging’. But it does not clearly state that the warming we are producing is going to persist for not just decades but centuries.

This moment of climate and ecological crisis demands much from our politicians, scientists, and societies. I would prioritise honesty. Any honest assessment of overshoot must acknowledge that we will have to find a way to live with whatever amount of warming we end up with. And this includes the consequences if we trigger climate tipping points such as the annihilation of warm water coral reefs (a certainty), the Greenland ice sheet (very likely but hopefully will take millennia), or the Atlantic Meridional Overturning Circulation (still uncertain, but alarmingly possible given latest science). There is no magic machine waiting in the wings that will wind the world back to its pre-industrial state. Scientists should know better to provide such narrative opportunities to politicians who use them to claim that there is no need to shift the Overton window of climate policy, no need to do anything radical.

Does this mean 1.5°C of warming is irreversible? Yes. But there is nothing particularly special about that amount of warming. Given record-breaking rates of emissions and temperature increases, the current amount of 1.4°C is just as irreversible. We are not about to produce a planetary-scale tipping event because we are passing 1.5°C. We are ‘just’ going to increase the scale of impacts, loss and damages. This increase may be very sudden. It may produce fracture points and break vital social system. Many people may die. But this is a million miles away from suggesting we give up trying to stop emissions, or that there is now nothing that can be done to save civilisation. Mitigation and adaptation become more important the warmer it gets. Why is this so difficult for some people to understand?

The UNEP report could have just said that death and suffering will increase until we stop forcing the climate system, and that if we want to reduce this death and suffering, we had better start figuring out how to implement transformative climate change adaptation alongside the rapid phase out of fossil fuels and reform of food production systems.

Them’s the facts. If policymakers deem them not relevant, then I'm sorry but we don’t have any others.