After the election of President Trump and a two-house Republican majority, many fear for the future of US climate policy. The new administration has indicated that they will abolish Obama’s climate legacy through executive orders.

The repeal of domestic measures will likely result in the US missing its first nationally determined contribution (NDC) under the Paris

Agreement, which is an inadequate target of reducing emissions by 26–28% compared to 2005 levels by 2025. If other countries

adopted comparable targets, global warming would likely exceed 2°C (ref. 2). The US would need to implement the Clean Power

Plan and additional measures to reach its NDC.

Preliminary research suggests that the policies of the Trump administration would instead lead to emissions increasing through to 2025.

Now the predominant concern for much of the international community is that the US will withdraw either from the Paris Agreement, or the overarching United Nations Framework Convention on Climate Change (UNFCCC). The former would take four years and the latter only one. Both are legally possible and within the presidential mandate.

The conventional wisdom is that a US withdrawal would be a worst-case scenario for international climate policy.