Negotiated targets on climate change mitigation are ineffective: States do not seek to exceed their unambitious targets when they could. An obligation of conduct – to do the maximum, based on a standard of due diligence – could be more effective.
https://www.theguardian.com/commentisfree/2020/jan/29/climate-targets-committee-on-climate-change-report
https://www.theguardian.com/commentisfree/2020/jan/29/climate-targets-committee-on-climate-change-report