Mexico, the fifth - largest methane emitter in the world in 2015, published regulations in 2016 for methane
emissions in its
upstream oil and gas operations, and
addressed methane in recently published guidelines for unconventional oil and gas development.
Given that, if one wants freedom of choice and an efficient market, shouldn't one accept a market solution (tax / credit or analogous system based on public costs, applied strategically to minimize paperwork (don't tax residential utility bills — apply
upstream instead), applied approximately fairly to both be fair and encourage an efficient market response (don't ignore any significant category, put all sources of the same
emission on equal footing; if cap / trade, allow some exchange between CO2 and CH4, etc, based CO2 (eq); include ocean acidification, etc.), allowing some approximation to that standard so as to not get very high costs in dealing with small details and also to
address the biggest, most - well understood effects and sources first (put off dealing with the costs and benifits of sulphate aerosols, etc, until later if necessary — but get at high - latitude black carbon right away)?