The Rajan Global Carbon Tax Proposal

Those countries that emitted CO2 above the global per capita average pay into a fund.
Those countries that emitted CO2 below the global per capita average draw from the fund.

This is inclusive and reconciles with C&C
Heuristic
Context

ABSOLUTE FRAMEWORK

Rules

a) Inclusive (global full-term).
b) Self-referential (full international carbon closure).
c) All play by the same rules.

References

a) Full-Term Carbon Budget (FTCB)
b) 2020 to absolute zero globally in 20 years
c) Fixed budget integral arising 137.5 Gt C
d) Price slope (rising % tax-rate) for years of FTCB
e) Revenue raised (e=a*d)
f) Global Per Capita Emissions Average (GPCEA) population base-year (2020)
g) Global Fund (GF) [a] receives & [b] disburses revenue raised
h) To those above & below the GPCA

GUESSWORK Relative to ABSOLUTE FRAMEWORK

We counted our way into this global crisis in a random manner. To get out of it we have collectively to
solve the problem faster than we (in fact only some of us) caused it. Denial is now effectively dead.

This means & also incontestably requires an integrated absolute framework of account to
count our way out of it now. In a phrase, we have to do enough soon enough collectively.

A race to carbon zero to do more than enough sooner than needed could well occur as result of this and the zeitgeist of increasing danger. All well and good, this may well be the strongest reason why we positively need (rather than need to to abandon) an absolute framework within which to integrate and account for such initiatives. Without it they are uncountable and also un accountable

From a pure economic perspective, all face the same equivalent global price on carbon.
Subject to a global cap, Mark Carney says this is the first-best solution.

By contrast the Fee & Dividend (F&D) Proposal

As intra-national borders define it, this proposal is not so much internationally unifying as divisive.
Advocacy of F&D accepts the status-quo and ignores the unequal history of CO2 emissions.

The Fee-&-Dividend (F&D) proposal came from James Hansen. F&D is a 'progressive' rather than a 'marginal' carbon-tax model. However indexing the shape of the carbon/F-&-D curves to no more that the safely available total of carbon emissions is necessary, if we are serious about acting to avoid catastrophic rates of climate change.

Doing this literally counts global carbon out by weight to zero by the given date. We can debate the start level of the tax ($10, $100 . . . ) till the ravens leave the tower, but the issue is going to zero carbon globally over the next twenty years.

In visual tems, when IPCC talks-the-talk of a carbon-budget for 1.5° C with a zero carbon path-integral globally within 18 years, carbon-taxing alla Fee-&-Dividend has a 'green man' that walks-the-walk as shown in the slides. Without this all we have is just another headless chicken which doesn't even know why it is trying to cross the road, let alone whether it intends to (or even knows how to) or not . . . .

What these curves clearly demonstrate is that over twenty years, we get better odds (66%) for achieving 1.5° C for less $(F-&-D) ($65 trillion), than if we opt for doing this over 32 years where we get worse odds (33%) for achieving 1.5° C for more $(F-&-D) ($190 trillion) and where the sky probably falls in.

So is this going to be the headless chicken that gets run over through yet more 'Emissions Creep', or the chicken that gives momentum to timely road-crossing rather than yet more road-kill?

As carbon is constantly being added to the total seen as 'safe' by researchers, things are not looking good. The latest example is from Comyn Platt et al, compared with what is being said by the IPCC. Here are some slides detailing this 'emission-creep'

James Hanse gave some welcome encouragement to the Judicial Review of the UK Climate Act