This article, a round-up of expert opinions from around the world, includes an extended comment from SEI Senior Research Fellow Richard Klein:
A U.S. withdrawal from the Paris Agreement – and the likely associated failure to curb US greenhouse gas emissions – would require other countries to increase their ambition if the goal of limiting global warming to 2°C or 1.5°C is to be met. However, I doubt that countries would be willing to do so already before the first global stocktake in 2023. Instead, I would expect countries to update their pledges in a second round of Nationally Determined Contributions, which also gives them the opportunity to monitor developments in the US (for example, at state level) and await the outcome of the presidential elections of 2020.
A possible defunding of the UNFCCC process would not only reduce the amount of money available to help developing countries take mitigation and adaptation action, but also incapacitate the UNFCCC Secretariat. This year the U.S. contributes 21% of the Secretariat’s core budget; it is unclear how the Secretariat could meaningfully fulfil its broadened mandate if this were to be fully cut.
Source: China Dialogue, China