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<bold>Abstract</bold> Net-zero greenhouse gas emission targets are central to current international efforts to stabilize global climate, and many of these plans rely on carbon dioxide removal (CDR) to meet mid-century goals. CDR can be performed via nature-based approaches, such as afforestation, or engineered approaches, such as direct air capture. Both will have large impacts in the regions where they are sited. We used the Global Change Analysis Model for the United States to analyze how regional resources will influence and be influenced by CDR deployment in service of United States national net-zero targets. Our modeling suggests that CDR will be deployed extensively, but unevenly, across the country. A number of US states have the resources, such as geologic carbon storage capacity and agricultural land, needed to become net exporters of negative emissions. But this will require reallocation of resources, such as natural gas and electricity, and dramatically increase water and fertilizer use in many places. Modeling these kinds of regional or sub-national impacts associated with CDR, as intrinsically uncertain as it is at this time, is critical for understanding its true potential in meeting decarbonization commitments.
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Leveling up net zero climate leadership in the United States:
Executive Summary ● As the Biden-Harris administration recommits the US to the Paris Agreement, a robust national net zero emissions strategy, integrated with local and corporate decarbonization targets, will ensure the nation achieves its climate goals. A new nationwide survey of current net zero climate commitments reveals the following: ● The US has a broad foundation of local net zero ambition on which to build a robust national decarbonization pathway. At least 53% of Americans live in a jurisdiction with a subnational net zero target. Furthermore, US companies accounting for at least $5.2 trillion in yearly sales have committed to net zero. ● Discrepancies in the quality of these targets highlight the need for strong federal leadership to raise the bar for existing subnational and corporate targets and spur further ambition to meet the goals laid out in the Paris Agreement.1 ● Existing state, local and private sector targets require improved alignment in governance mechanisms, consideration of equity and use of offsets. ● To achieve net zero emissions in the US by 2050 in an equitable, just, and leastcost manner, the White House Climate Task Force and Congress should enact policies to strategically strengthen and grow subnational and corporate ambition. In conjunction, subnational and corporate actors must continue to set and improve upon existing targets. ● Our empirical findings indicate a strong basis of support for federal policymakers to implement a robust national net zero strategy. Four key policies will enable government leaders to connect ambition to action: ○ Pledge: Include a robust net zero pledge in the US’ Nationally Determined Contribution (NDC) submission that exceeds the United Nations Framework Convention on Climate Change (UNFCCC) Race to Zero minimum criteria and adopts key leadership practices. These practices include creating a pledge that is codified in law, covers all greenhouse gases across operations and supply chains and includes an interim target of 50% emissions reductions by 2030. ○ Plan: Publish a national net zero roadmap that includes considerations of equity and justice and places constraints on the role of offsets. ○ Proceed: Align economic recovery spending with the aims of the net zero target, develop sector-specific net zero benchmarks and template strategies and mandate net zero alignment as a condition for federal bailouts. ○ Publish: Publish an annual national progress report that includes the progress of subnational commitments.
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- Award ID(s):
- 1633740
- PAR ID:
- 10285819
- Date Published:
- Journal Name:
- Smith School working paper series
- ISSN:
- 2732-4214
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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