I have turned the graph above into a short paper for the Institute of Energy Economics, Japan (here in PDF). Here is how it starts:

International climate policy is incredibly complex. The field is highly technical and characterized by an esoteric jargon that is spoken by insiders who have dedicated their careers to the aim of coordinating an international response to the threats posed by the accumulation of greenhouse gases in the atmosphere. As a result, for many policy makers and the informed public, understanding climate policy can be a challenge. To help observers who may not be insiders to better understand climate policy, this essay presents a straightforward approach to tracking international (and national) progress with respect to the implementation of the Paris Agreement.

To read the rest, find it at IEEJ in PDF.