Would constraining US fossil fuel production affect global CO2 emissions? A case study of US leasing policy

Avoiding dangerous climate change will require a rapid transition away from fossil fuels. By some estimates, global consumption and production of fossil fuelsparticularly coal and oilwill need to end almost entirely within 50years. Given the scale of such a transition, nations may need to consider policies that constrain growth in fossil fuel supplies in addition to those that reduce demand. Here, we examine the emissions implications of a supply-constraining measure that was rapidly gaining momentum in the United States (US) under the Obama administration: ceasing the issuance of new leases for fossil fuel extraction on federal lands and waters. Such a measure could reduce global carbon dioxide emissions by an estimated 280 million tons annually by 2030, comparable to that of other major climate policies adopted or considered by the Obama administration. Our findings suggest that measures to constrain fossil fuel supplythough not currently viable in a US Trump administrationdeserve further consideration at subnational levels in the US or by other countries now, and by future US administrations.