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The second session of the Conference of the Parties (COP 2) to the UN Framework Convention on Climate Change--held July 8-19, 1996, in Geneva, Switzerland--was attended by 948 delegates from [...]

Water is a resource that already has been affected by some aspects of global change and whose availability in time and place may be substantially further altered by global warming. As human demands and impacts on water resources have increased, institutions governing water use have evolved in response to pressures exerted by competing resource users. The record of such institutional evolution and its implications for the impacts of environmental change on human welfare can provide a glimpse of issues that are likely to arise as other natural resources are increasingly subject to the effects of global environmental transformations. Efforts to manage multiple interdependent water uses present informative analogies to the general problem of managing the many interrelated aspects of global change.

The release of carbon monoxide and other greenhouse gases (GHGs) is a global problem because these gases remain in the atmosphere for decades and affect the climate. The solutions to the problem may be attained either through the noncooperative or the cooperative, global-utility-maximization methods. A comparison of these two methods using game analysis disproves several assumptions, such as substantial differences between these two. The absence of such differences, in turn, suggests that global agreements are not as crucial to climate change limitations as had been previously assumed.

This paper offers an overview of the authors' studies during a specialized international symposium (Mexico, 22 November-1 December 1993) where they aimed at making an objective assessment of whether climate changes, consequent on an expected doubling of atmospheric C[O.sub.2] in the next six or seven decades, are likely to increase significantly the frequency or intensity of tropical cyclones (TC). Out of three methodologies available for addressing the question they employ two, discarding the third for reasons set out in the appendix. In the first methodology, the authors enumerate reasons why, in tropical oceans, the increase in sea surface temperature (SST) suggested by climate change models might be expected to affect either (i) TC frequency, because a well-established set of six conditions for TC formation include a condition that SST should exceed 26 [degrees] C, or (ii) TC intensity, because this is indicated by thermodynamic analysis to depend critically on the temperature at which energy transfer to air near the sea surface takes place. But careful study of both suggestions indicates that the expected effects of increased SST would be largely self-limiting (i) because the other five conditions strictly control how far the band of latitudes for TC formation can be further widened, and (ii) because intense winds at the sea surface may receive their energy input at a temperature significantly depressed by evaporation of spray, and possibly through sea surface cooling. In the second methodology, the authors study available historical records that have very large year-to-year variability in TC statistics. They find practically no consistent statistical relationships with temperature anomalies; also, a thorough analysis of how the El Nino-Southern Oscillation cycle influences the frequency and distribution of TCs shows any direct effects of local SST changes to be negligible.