The Paris Agreement in the 2020s: Breakdown or Breakup?

[Noah M. Sachs is a Professor of Law and the Director of the Merhige Center for Environmental Studies at the University of Richmond School of Law]

This December, the Paris Agreement turns four years old, still in its toddlerhood. Will it prove to be a durable treaty, maturing and strengthening over time? Will it be effective when it reaches middle age in the 2050s, when global emissions need to be reduced to near zero?   

In my new article, “The Paris Agreement in the 2020s: Breakdown or Breakup?”, forthcoming in Ecology Law Quarterly, I argue that these scenarios are overly optimistic. The Paris Agreement is in danger of faltering or even collapsing. While other scholars have noted the possibility of failure, I show how and why a downward spiral could unfold. 

The warning signs are already here: from President Trump’s withdrawal announcement in 2017 to the latest data that show that states are not on track to achieve even their initial, modest emissions reductions pledges, called Nationally Determined Contributions (NDCs). Meanwhile, the global carbon emissions budget consistent with the two-degree Celsius temperature goal of the Agreement is being rapidly depleted. After flattening from 2014 to 2016, global emissions are again reaching record annual highs.   

Given these stressors, I argue that the Paris Agreement could plausibly fall into a scenario that I call “Breakdown,” where parties slow-walk or low-ball their climate pledges, pursuing symbolic gestures and telling the world “this is all we can do.” Under Breakdown, the Agreement would still provide a forum for negotiations, but the collective pledges of states will be seriously insufficient to halt runaway warming.

Even worse, the Agreement could fall into a scenario that I call “Breakup.” In Breakup, parties would begin to defect, withdraw, or otherwise disengage from Paris, following the path forged by President Trump. The two scenarios are not mutually exclusive. In the 2020s, Breakdown could lead to Breakup, and it is difficult to predict what would lie on the other side of Breakup, which would involve the collapse of the Paris Agreement.

Re-election of President Trump in 2020 would make Breakdown and Breakup far more likely, but even if the US were to rejoin the Paris Agreement in 2021, Breakdown or Breakup could still occur. Harold Koh, who said that, “Trump’s withdrawal announcement has no more legal meaning than one of his tweets,” was overly sanguine. 

In my view, the 2017 announcement did serious damage – although the US withdrawal does not take effect until November 2020 – because it undermined the universality and reciprocity of the Agreement. That damage will not be easily repaired in the 2020s even under Democratic presidents, especially if the US Senate remains a graveyard for climate legislation.   

My paper challenges the dominant scholarly and diplomatic narrative about the Agreement, which is that parties will pressure each other, in a virtuous circle of cooperation, to strengthen emissions reductions over time – a view I call the “Peer Pressure Proposition” (PPP). Achieving NDCs is purely voluntary, so proponents of the PPP believe that informal pressure and reputational norms, coupled with “naming and shaming” strategies by states and NGOs, will propel parties to ratchet up their NDCs over the next few decades. 

The PPP rests on several flawed assumptions, however.   

The PPP does not adequately account for the domestic pressures that governments will face in the 2020s that will likely outweigh any concerns about international reputation. Emissions reductions will be costly. Many major emitters (e.g., China, India, Russia, the US) are still building out a fossil-fuel infrastructure that will last beyond mid-century. Yet the science is now clear that to stay on a trajectory consistent with the two-degree temperature goal of the Agreement, global emissions would have to peak by 2025 and then decline 5-8% per year thereafter. This rate is far faster than any nation has ever achieved, and it would have to be achieved globally. Incumbent industries will act as a drag on parties’ ambition, and these domestic pressures will weigh heavily in states’ calculus of what they can pledge internationally.

In the paper, I also question the assumption that parties will suffer a reputational “hit” if they fail to achieve NDCs. NDCs are non-binding climate pledges that all parties conceded from the outset were aspirational. “Naming and shaming” strategies are unlikely to be successful for this reason, and they have not worked in the past in the climate change regime.

The PPP also rests on the assumption that parties will be willing to make ambitious commitments because the commitments themselves will be easier to achieve – economically, technologically, and politically – over time. As we enter the 2020s, however, this looks like wishful thinking. Population growth and economic growth through mid-century will likely swamp any emission reductions attributable to better technology, and in many major emitting states, populist and nationalist leaders are retrenching on climate. The assumption of easier progress may hold for some states and technologies, but it is not a generalizable, bankable proposition for the world.

In the end, I conclude that the fractures in the Paris Agreement are not attributable to any particular text or flaw in the treaty. Instead, they are occurring because climate change is a super-wicked collective action problem, involving both intra-generational and inter-generational prisoners dilemmas. The climate regime is also plagued by longstanding arguments between developing and developed states over equity and financing. The Paris Agreement may have papered over these conflicts for a while, but it has not solved them.  

Policymakers therefore need to be prepared for Breakdown and Breakup. It will become apparent by the middle of the decade that the Paris Agreement is not driving the necessary reductions in global emissions, and the political fallout is not likely to be a fuller embrace of the Agreement. Instead, uncommitted states may head for the exits, and committed states may search for an alternative coalition or framework for emissions reductions. Intense arguments between developed and developing states about burden-sharing, largely avoided at Paris, will come roaring back this decade as an implicit allocation of effort will become apparent to all parties.

It is too soon to predict any outcome with certainty, but Breakdown or Breakup scenarios are now plausible outcomes for Paris. Scholars and diplomats need to treat these as realistic scenarios. Either scenario would be ecologically devastating.