evidence: Happer, for example, says that climate-change advocates ignore the fact that there have been several periods, including the last 10 years, in which there has been no warming, and that temperatures in fact cooled during the period from roughly 1940 to 1970. Sea levels are indeed rising, he also says, but they have been rising since the end of the last Ice Age, and there is no evidence that the rate is increasing. Suckewer adds that his own research has convinced him that human activity has little to do with rising CO2 levels, much of which is caused by water vapor and ocean currents. Those forces, he says, are so vast, complex, and imperfectly understood that efforts to "fix" them would be folly. [...] One more crucial observation is that rising sea levels are almost certainly not the most immediate threat implied by the current dynamics within the world meteorological system. Much more devastating would be more frequent and violent weather events, severe multiyear shifts in rainfall patterns producing destructive floods or droughts, collapse of ecosystems upon which human populations depend, and the interruption of the flow of major ocean currents due to buildup of fresh water on the surface of the oceans. Any or all of the above could occur without any major shift in the mean values of any "key variable" such as CO2 emissions.