The top 4 emitters – China, the USA, India, and Russia – account for 55% of annual CO2 emissions from fossil fuels. These country emissions are anthropogenic and exogenous to physical-science based climate modelling.
To develop an understanding of the anthropogenic contribution to future CO2 concentrations, there is a need for country specialists in the politics, energy policies, environmental regulations, and economics of each substantial emitter.
Whereas each successive COP meeting generates easily accessible and centrally collated statements of CO2-reduction intent, nations will differ in the extent to which these commitments are monitored and enforced. Already at this time, there is great variability between countries in the probability of achieving Paris Agreement Goals. These dynamics fall squarely within the social and policy sciences, which currently receive only a tiny fraction of climate research funding.