Getting hot in Rio

National Review, June 22, 1992 by Ed Rubenstein

AS COMPLICATED as the matter is, it appears that magnetic storms on the sun may have more to do with the earth's climate than the build-up of greenhouse gases on earth, according to a recent study by scientists at the George C. Marshall Institute.

Rising solar activity recorded over the past 100 years is consistent with a 0.7 per cent brightening of the sun--enough to explain the entire 0.5[degrees]C global warming over this period. The sun's pervasive influence is also confirmed by analysis of the amount of Carbon-14 in ancient tree rings. The isotope, known to fluctuate with solar activity, rises and falls by substantial amounts every 200 to 300 years, invariably presaging major changes in climate.

The greenhouse model, meanwhile, cannot explain the rapid rise in global temperature in the decades prior to 1940, or why average temperature dropped between 1940 and 1970, a period of rapid growth in [CO.sub.2] emissions but declining solar activity. This suggests that the worst-case scenario--a doubling of [CO.sub.2] and other greenhouse gases over the next century--would raise global temperatures by less than 1[degrees]C, and maybe less than 0.5[degrees]C.

The lack of hard greenhouse evidence hasn't stopped participants in the Rio "Earth Summit" from pushing for caps on CO2 emissions. (See table.) The world's advanced nations, with less than 25 per cent of world population, produce roughly 60 per cent of annual CO[.sub.2] emissions. If the UN, in its infinite wisdom, were to distribute [CO.sub.2] quotas on a per-capita basis, the industrialized nations would have about a third (the U.S. less than one-quarter) of what is needed to produce at current levels.

The less developed countries (LDCs), on the other hand, could reap a cash windfall by selling their excess [CO.sub.2] entitlements to developed nations. The market price for such quotas, according to a recent study, could reach $25 to $75 per ton, implying a transfer of up to $200 billion annually from the developed to the developing world. (Foreign aid from the OECD nations to LDCs is, by contrast, a mere $50 billion.)

A prudent policy would weigh economic costs against likely environmental benefits. A 20 percent reduction in [CO.sub.2] emissions, favored by many Greens, would require that gasoline prices increase by $1.30 per gallon (1990 dollars), electricity rates double, and the oil price by $60 a barrel. According to the Department of Energy, this would cost the economy nearly $100 billion by the end the decade.

Share of Global Emissions
Population, and GNP, 1986
                              Other        Less
                            Industrial   Developed
                       U.S.    Nations    Countries
[CO.sub.2] Emissions   23%      37%         30%
Population              5       18          77
GNP                    26       58          16