Dr. Desmet, along with coauthors Bruno Conte and Esteban Rossi-Hansberg, discuss how a unilateral carbon tax introduced by the United States or the European Union may be a boon for the world, even in the short run. This Vox EU column goes into more discussion.
However, carbon taxes are economic measures aimed at reducing greenhouse gas emissions and mitigating the impacts of climate change. The idea is that by putting a price on carbon emissions, it becomes more expensive to engage in activities that contribute to climate change, thus encouraging individuals and businesses to reduce their carbon footprint. The researchers you mentioned may have studied the potential impact of such a policy on a global scale, including its potential benefits even if only one region (the US or EU) were to implement it.
Kirsis Fernandez: https://www.homeworkminutes.com/tutors/profile/kay/