The search for a single and simple measure for each country’s contribution to global warming is unlikely to succeed, new research has warned.
The question of how to fairly quantify national contributions to global warming historically, and inform future policy on sharing the burden of reducing greenhouse gas emissions, has long been part of international discussions on global warming.
Researchers from the Center for International Climate and Environmental Research Oslo (CICERO) and the University of Oxford, UK, assessed if finding an answer to this question was possible or likely.
Dr Steffen Kallbekken, from CICERO, said: “There are vast differences in income, population, resources, technologies and capacity across countries. Because of this, the idea of distributive fairness has played a crucial role in the international climate policy debate.
“However, trying to find a single common formula for policymakers to decide the distribution of national efforts in a climate agreement was never likely to succeed.
“Although it references equality principles, the United Nations Framework Convention on Climate Change 2016 Paris Agreement tacitly recognises this fact, as in practice the differentiation is left to each country to decide for itself.”
Dr Jan Fuglestvedt said: “Our results indicate there is no simple and single correct answer to the question of how much each country has contributed to global warming. There are too many fundamental value-related and ethical questions remaining, to which it is impossible to find a single answer.
“A more useful approach would be for scientific studies to present not just one set of calculated contributions – based on some of many choices – instead present a spectrum of results showing how the contributions vary according to a broad set of choices.”