The analysis presents scenarios showing what levels of greenhouse gas emissions would be if the world population was at a benchmark per capita GDP comparable to several European nations that currently have the lowest greenhouse gas emissions per million dollars of GDP among all developed nations. Eight of the top-20 per capita GDP nations achieve greenhouse intensities below 110. The implication for the two goals of economic growth and of constrained emissions is clear: if economies grow and population is stable or rises, emissions will rise unless intensity decreases enough to offset the rise. Defining an Economic Benchmark

As shown by Table 1 , eight nations combined a greenhouse gas intensity of less than 110 tons per million dollars GDP with per capita GDPs of $23,490 or better. Per capita emissions and greenhouse gas intensity (emissions per unit of economic activity) have also been discussed as metrics for defining emissions goals. This compares to actual 2000 world GDP of $44 trillion and emissions of 9.1 billion tons. This analytical construct could be applied globally, to individual nations, or to groups of nations. One can calculate the implications of different population levels, different economic development levels, different emissions goals, etc. At a population of 6 billion, achieving a parity GDP of $23,500 and an intensity of 100, global greenhouse gas emissions would be 14.1 billion tons (+55%). Or, if one thought that a parity level of $23,500 were too high, one could calculate the implications of a lower level, say an average per capita GDP of $15,000 (slightly more than double the 2000 world average per capita GDP):
At the 2000 population of 6 billion, an intensity of 100, an average per capita GDP of $15,000 (and ignoring grandfathering), emissions would be 9 billion tons, slightly lower than the 2000 level. Greenhouse gas intensity has been improving globally, and in many nations. The purpose of this analysis has been to give some tangible sense of a possible outcome from pursuing competing goals—economic growth and development versus constraining greenhouse gases—that are confounding efforts, such as the United Nations Framework Convention on Climate Change (UNFCCC) and the Kyoto Protocol, to address global climate change. For some, the finding that one can construct an empirically based approach that achieves a standard of living for the existing population equal to that of several European nations while not increasing global greenhouse gas emissions by more than 60% will be optimistic. For others, the emissions may appear unacceptable despite the improvement in intensity—which could imply even more aggressive improvements in intensity and/or constraints on economic growth. For still others, worry about greenhouse gas emissions is misdirected.
This analysis identifies those nations that have combined the highest per capita GDPs with the lowest intensities of greenhouse gas emissions. Taking those nations as exemplars, it then examines possible outcomes from pursuing competing goals—economic growth and development versus constraining greenhouse gases—that are confounding efforts, such as the United Nations Framework Convention on Climate Change (UNFCCC) and the Kyoto Protocol, to address global climate change.
Eight nations—Austria, France, Italy, Iceland, Luxembourg, Norway, Sweden, and Switzerland—combine high per capita GDP (among the top-20 nations) with the lowest intensity of greenhouse gas emissions of all nations (between 107 and 70 tons per million $GDP). Taking the lower level of their per capita GDP ($23,500) and an intensity of 100, this analysis examines the greenhouse gas emission implications of a world achieving those levels of economic activity and greenhouse gas intensity.
The relationship of population, economic growth, and emissions is defined by:
(population) x (per capita GDP) x (intensity) = emissions
This relationship can be applied globally, to individual nations, or to groups of nations. One can calculate the implications of different population levels, different economic development levels, different emissions targets, etc. Obviously if population rises, emissions will rise unless per capita GDP and/or intensity decrease enough to offset the rise; likewise, if per capita GDP rises, emissions will rise unless intensity (and/or population) decrease enough to offset it.
With the formula, one could test numerous variations; this analysis focuses on the one empirically-based set, a global per capita GDP of $23,500, an intensity of 100, and the 2000 world population of 6 billion. With those assumptions, greenhouse gas emissions would be 14.1 billion tons per year, about 55% more than the 9.1 billion tons actually emitted in 2000.
Whether global greenhouse gas emissions of 14.1 billion tons per year (or more as population increases) would pose a threat of global warming sufficient to justify impeding that economic development and/or stimulating even more aggressive action to improve greenhouse gas intensity awaits growing scientific understanding and the decisions of world leaders—and the manifestation of events.
For some, the finding that one can construct an empirically based approach that achieves a standard of living for 6 billion people equal to several European nations while not increasing global greenhouse gas emissions by more than about 55% will be optimistic. For others, the emissions level may appear unacceptable—implying either constraints on economic growth or even more aggressive improvements in intensity. For still others, any worry about greenhouse gas emissions is misdirected.
This report will not be updated.