The legal character and operational relevance of the Paris Agreement's temperature goal

This article assesses the legal character and operational relevance of the Paris Agreement's 1.5 degrees C temperature goal. This article begins with a textual analysis of the 1.5 degrees C goal. It considers whether the goal creates individual or collective obligations for Parties, and whether it is sufficiently specific to enable the tracking of individual or collective performance. Next, it assesses the operational relevance of the 1.5 degrees C temperature goal, by considering the role it will play in the Paris Agreement's institutions and procedures. To the extent that the goal plays a role, and implies global limits on greenhouse gas emissions, this article observes that it could have implications for the sharing of the effort between Parties. Thus, this article considers the relevance of equity and the principle of common but differentiated responsibilities and respective capabilities, in the light of different national circumstances, to understanding how the 1.5 degrees C goal could be reached. In this context, this article explores whether the 1.5 degrees C goal could play a role in the Paris Agreement's 'ambition cycle'. Finally, this article asks whether there are any legal or political implications, individually or collectively under the Paris Agreement, should the Parties fail to achieve the 1.5 degrees C goal. This article is part of the theme issue 'The Paris Agreement: understanding the physical and social challenges for a warming world of 1.5 degrees C above pre-industrial levels'.