17 November 2016. Trump has been unequivocal. Global warming, he claims, is a hoax "created by and for the Chinese in order to make US manufacturing non-competitive". The right thing for the government to do, he has promised, will be to repudiate the Paris Agreement as soon as possible. There is little to suggest he will not follow through on that promise.

Some seem to think this will make only a minor difference for the Paris Agreement. Since the agreement is now in force, it will legally bind the US just like it legally binds the other 102 countries that have ratified it so far. Moreover, parties may only withdraw from the agreement in three years, and that withdrawal would take legal effect only another year later. By then, the next presidential elections could turn the tide again. But even without the US, could the other nations stick to their commitments and still build their efforts to fight against global warming on the agreement they have reached in Paris?

That view is flawed. Legally, the US could immediately withdraw from the 1992 UN Framework Convention on Climate Change, which the Paris Agreement is meant to help implement. Such a withdrawal would take effect within one year. By early 2018, the US could thus be exempt from any international obligations related to climate change. Surely, the US would then be the only country in the world that does not recognize the convention. But that may mean little to a president who campaigned on an anti-establishment ticket and believes global warming to be a conspiracy.

No sanctions

More importantly, the view that the Paris Agreement will survive the election of Donald Trump is politically naïve. As a part of the agreement, countries have set their own "nationally determined contribution" (NDC). The US has promised to reduce its CO2 emissions by 26 to 28 per cent by 2025, compared to 2005 levels. Yet, if the US fails to reduce its greenhouse gas emissions, no sanctions will follow. With its bottom-up approach, the Paris Agreement is as far from "world government" as one could possibly imagine.

Precisely because it lacks an enforcement mechanism, the agreement is a tit-for-tat. The logic is simple: I will cooperate, if you cooperate. Thus, the agreement primarily serves two functions: It allows states to make promises, considering the promises other states are making; and it allows states to verify if others are keeping the promises they made. The only sanction the agreement envisages lies in the expectation that, if one big emitter cheats, cooperation will break down and leave all parties worse off. To put it simply: if the US seeks a competitive advantage by failing to comply, why would China contribute?

Possible scenarios

What could happen now? The first scenario is the one we seek to avoid: unrestricted global warming in the absence of global cooperation. It would leave our children and grandchildren a different and less inhabitable planet. The election of a global-warming sceptic as the next US president brings us one step closer to this scenario. Second, we can imagine a technological breakthrough to rescue us from global warming. But since such breakthroughs cannot be planned, to rely on this deus ex machina means to bet on luck. Third, there is climate engineering: a range of options from large-scale afforestation for carbon capture and storage, ocean fertilisation and solar-radiation management. We currently know little about most of these options. But what we do know is that they involve plenty of risks.

Finally, states could reanimate climate cooperation without the US. The experience from Kyoto suggests this will be a tough challenge. But since many countries have set their economies on a path towards cleaner energy in the meantime, the world economy has changed since Kyoto. If a strong, committed and diverse coalition of states emerges, it could thus seek to rescue key elements of the Paris Agreement, possibly combining them with a border-tax-adjustment scheme for products originating from countries that remain outside the regime.

This option is worse than the original Paris Agreement, but it is better than any of the alternative scenarios we face. Governments should thus use their annual climate talks in Marrakesh this month to quickly adapt to the new reality of climate governance. It is a reality in which the US will – at least for the next four years – no longer be on board.

Picture: Fotolia / firewings