We present a framework for allocating a global carbon reduction
target among nations, in which the concept of ‘‘common but
differentiated responsibilities’’ refers to the emissions of individuals
instead of nations.... We then propose a simple rule to derive a universal cap on global
individual emissions and find corresponding limits on national
aggregate emissions from this cap....For example, reducing
projected global emissions in 2030 by 13 GtCO2 would
require the engagement of 1.13 billion high emitters, roughly
equally distributed in 4 regions: the U.S., the OECD minus the U.S.,
China, and the non-OECD minus China. We also modify our methodology
to place a floor on emissions of the world’s lowest CO2
emitters and demonstrate that climate mitigation and alleviation
of extreme poverty are largely decoupled.
National responsibilities are derived by summing the excess emissions of all ‘‘high emitter’’
individuals in a country—‘‘high emitters’’ are those whose
emissions exceed a universal individual emission cap. The
scheme does not specify how any nation meets its responsibilities.
Maybe I'm missing something, but this sounds like another way to describe a per-capita emission allocation - not that it's a bad thing, I think per-capita is the only fair way to go. The advantage might be in the marketing - focusing on super-polluters tends to disarm the status quo defenders.
In some ways this approach would discriminate against developed nations that have controlled their population growth and will continue to accept immigrants from other nations. On the other hand, legacy emissions from the last 150 years aren't addressed, so it might even out.
The authors note a trade issue: "By imputing national emissions to individuals, we neglect embedded carbon in exports and imports, a component that is relevant for countries with
large shares of trade in their economy.... a complete scheme suitable for use in negotiations would need to take them into account." I think that's one reason why the tariff component in the Waxman-Markey legislation is a good idea (along with the importance of using international agreements that aren't treaties to move forward on climate).