If all this is not discouraging enough, we now have even more to worry about.  The recently released Amsterdam Declaration on Global Change states that "in addition to the threat of significant climate change, there is growing concern over the ever-increasing human modification of other aspects of the global environment and the consequent implications for human well-being."  These modifications are said to be occurring to earth's atmosphere, land surface, oceans, coasts, water cycle, biogeochemical cycles and biological diversity.  Many of the phenomena involved in these modifications, according to the authors of the document, "are characterized by critical thresholds and abrupt changes."  Human activities, they say, "could inadvertently trigger such changes with severe consequences ... that may prove irreversible and less hospitable to humans and other life."

But doesn't the coin of the environmental realm have two sides?  Couldn't some of the random, unforeseen consequences of humanity's activities be positive?  The Amsterdam Declaration correctly states that "global change cannot be understood in terms of a simple cause-effect paradigm."  Human-driven changes, it notes, "cause multiple effects that cascade through the Earth System in complex ways," and "these effects interact with each other and with local- and regional-scale changes in multidimensional patterns that are difficult to understand and even more difficult to predict."  Indeed, the authors of the Declaration openly admit that "surprises abound."  Might not some of them be good?

Apparently not, at least in the minds of the enlightened few who wrote the document.  "The accelerating human transformation of the Earth's environment is not sustainable," they bluntly state without supporting materials.  And that is probably why they call their document a declaration; for declarations often state self-evident truths that need no ancillary support, such as was the case with the document that launched the enterprise we call the United States.  The problem with this approach, however, is that the declarative sword cuts two ways; and it can just as easily be used to promote not-so-evident falsehoods.

Consider the carrying capacity of the planet.  According to a high-profile report released at the conference that produced the Amsterdam Declaration, "forty of the world's poorest nations are likely to suffer food production losses of more than 20% over the coming decades due to global warming."  This conclusion is clearly based upon "a simple cause-effect paradigm" of the type the Amsterdam Declaration rightly says cannot be used to properly describe the effects of global change, which "cascade through the Earth System in complex ways," along with other simultaneously-cascading interrelated effects.

Ratcheting up the complexity of the subject just one level, for example, it is obvious (should we say self-evident?) that we must also consider the aerial fertilization effect of the phenomenon that is supposed to drive global warming, i.e., the ongoing rise in the air's CO2 content.  Doing so, we find that for the increase in atmospheric CO2 that is predicted to lead to the warming that is stipulated to decrease food production, there is a direct CO2-induced increase in crop productivity that is more than sufficient to compensate for the warming-induced decrease in growth.  In fact, we typically find that in CO2-enriched air the temperature at which plants perform at their optimum actually rises -- by as much as 5°C for a 300 ppm increase in the air's CO2 concentration (Long, 1991; Idso and Idso, 1994) -- suggestive of the likelihood that agriculture would actually prosper in a warmer and CO2-enriched world.

At the very highest air temperatures encountered by plants, atmospheric CO2 enrichment has also been shown to be beneficial -- extremely beneficial, in fact -- considering elevated CO2 concentrations can sometimes mean the difference between a plant's living or dying.  It has been experimentally demonstrated, for example, that plants growing in CO2-enriched air are often able to maintain a positive leaf carbon exchange rate (net photosynthesis rate), when plants growing under ambient CO2 concentrations exhibit negative rates that ultimately lead to their demise (Idso et al., 1989, 1995).

Then, of course, there's the well-known tendency for atmospheric CO2 enrichment to reduce plant stomatal conductances (Pallas, 1965; Morison, 1985), which phenomenon results in lower rates of transpirational water loss from vegetation (Kimball and Idso, 1983; Cure and Acock, 1986), which helps plants better deal with periodic drought and chronic soil moisture deficiencies.  Indeed, the list of CO2-induced benefits goes on and on, to which fact fully half of our website stands as an irrefutable testament.

So why, we ask, have the leaders of so many nations gone berserk over the ever-so-faint possibility of CO2-induced global warming, especially when a veritable cornucopia of direct experimental observations clearly demonstrates the host of very real and much-to-be-desired biological benefits that accrue from atmospheric CO2 enrichment?  Clearly, the answer is not rooted in science, nor is it to be found in morality; for ethics demands that a demonstrable good be allowed to occur and not stopped in its tracks.

Many times in the past we have described the great need for the air's CO2 content to be able to rise unimpeded by Kyoto-type actions in order to meet the dietary requirements of the planet's burgeoning population, as well as increase the robustness of its natural ecosystems.  We here reiterate that fact and say, yes, good things do happen to the planet now and then; and the ongoing rise in the atmosphere's CO2 concentration is one of the best of those things to come along since the dawn of history.  It would be the saddest of ironies if humanity now tries to stop the very phenomenon that is the hope of its future.

References
Cure, J.D. and Acock, B.  1986.  Crop responses to carbon dioxide doubling: a literature survey.  Agricultural and Forest Meteorology 8: 127-145.

Idso, K.E. and Idso, S.B.  1994.  Plant responses to atmospheric CO2 enrichment in the face of environmental constraints: a review of the past 10 years' research.  Agricultural and Forest Meteorology 69: 153-203.

Idso, S.B., Allen, S.G., Anderson, M.G. and Kimball, B.A.  1989.  Atmospheric CO2 enrichment enhances survival of Azolla at high temperatures.  Environmental and Experimental Botany 29: 337-341.

Idso, S.B., Idso, K.E., Garcia, R.L., Kimball, B.A. and Hoober, J.K.  1995.  Effects of atmospheric CO2 enrichment and foliar methanol application on net photosynthesis of sour orange tree (Citrus aurantium; Rutaceae) leaves.  American Journal of Botany 82: 26-30.

Kimball, B.A. and Idso, S.B.  1983.  Increasing atmospheric CO2: effects on crop yield, water use and climate.  Agricultural Water Management 7: 55-72.

Long, S.P.  1991.  Modification of the response of photosynthetic productivity to rising temperature by atmospheric CO2 concentrations: has its importance been underestimated?  Plant, Cell and Environment 14: 729-739.

Morison, J.I.L.  1985.  Sensitivity of stomata and water use efficiency to high CO2.  Plant, Cell and Environment 8: 467-474.

Pallas, J.E.  1965.  Transpiration and stomatal opening with changes in carbon dioxide content of the air.  Science 147: 171-173.