Nationally determined contributions (NDCs)—country-specific commitments to reduce emissions—are the backbone of the Paris Agreement. In 2020, countries were requested to submit new or updated NDCs. The idea of a 50 percent reduction in greenhouse gas emissions (from 2005 levels) by 2030 has emerged in the United States as a focal point of discussions around future commitments in order to put the country on a path to net zero by midcentury. 
On April 15, 2021 Resources for the Future (RFF) hosted a webinar on what’s needed to achieve economy-wide, deep decarbonization in the United States. The conversation included words from six leading analysts who have modeled possible net-zero pathways. Each study author shared reflections on relevant findings, including:
- What emissions reductions can be achieved by 2030, and at what cost?
- What are the key sectors and technology pathways to achieving this result?
- What are the critical technology and cost assumptions underlying these results?
- How do choices concerning the 2030 milestone position the United States for more ambitious future goals?
The conversation explored similarities and differences across the studies, aiming to shed light on points of divergence and the overall feasibility of “50 by 30.”
- Tory Clark, Energy + Environmental Economics (E3)
- Leon Clarke, Joint Global Change Research Institute
- Marc Hafstead, Resources for the Future
- Ryan Jones, Evolved Energy Research
- Erin Mayfield, Princeton University
- Mei Yuan, Massachusetts Institute of Technology
- Karen Palmer, Resources for the Future (moderator)
 On April 22, 2021, the Biden administration announced a new emissions target for the United States: a 50–52 percent reduction from 2005 levels by 2030. Read the White House Fact Sheet for more information.