Whereas I can agree with the statement that our best guess is that observable effects in the year 2030 are likely to be ‘well short of catastrophic’, it is distinctly possible that the CPD scenario will later produce effects which will indeed be catastrophic (at least for a substantial fraction of the earth’s population). This is because the global ecosystem in 2030 might still be in a transient, headed for much more significant effects after time lags perhaps of the order of decades. If this indeed turns out to be the case it is very likely that we will unambiguously recognized the threat by the year 2000 because of advances in climate modeling and the beginning of real experimental confirmation of the CO2 effect,” Cohen wrote (emphasis added) I would feel more comfortable if the first paragraph concluded with a statement to the effect that future developments in global data gathering and analysis, along with advances in climate modeling, may provide strong evidence for a delayed CO2 effect of a truly substantial magnitude, a possibility with increases the uncertainty surrounding the post-2000 CPD scenario.