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The Most Important Global Change
Volume 4, Number 8: 21 February 2001

In a special issue of the international journal Agriculture, Ecosystems & Environment (1), J.S. Wallace of the UK's Centre for Ecology and Hydrology makes some important observations about the state of the earth, leading him to conclude that "the massive and inexorable increase in the number of human beings in the world should be recognized for what it is - the most important global change facing mankind."

The rationale behind this statement derives from four simple facts.  First, the projected increase in the number of people that will join our ranks in the coming half-century - a median best-guess of 3.7 billion - is more sure of occurring than is any other environmental change currently underway or looming anywhere on the horizon.  Second, these extra people will need a whopping amount of extra food.  Third, it will take an equally whopping amount of extra water to grow that extra food.  And fourth, there is no extra water.

"Over the entire globe," therefore, says Wallace (2000), "a staggering 67% of the future population of the world may experience some water stress," which translates into food insufficiency.  And food insufficiency means malnutrition and, in the most extreme cases, starvation.

So what's the solution?  There's only one answer, according to Wallace: We must produce much more food per unit of available water.  Which leads to the most important question of all: How can it be done?

Wallace discusses in some detail what would appear to be the only alternatives.  First, he suggests we must greatly augment water conservation measures wherever possible and implement every conceivable efficiency-enhancing procedure in irrigated and rain fed agriculture.  Second, we must do everything we can, as he says, "to fix more carbon per unit of water transpired."  That is, we must strive to dramatically increase plant water use efficiency.

Human ingenuity will surely enable great strides to be made in all of these areas over the coming decades.  But will the improvements be large enough?  At the present time, no one can answer this question with any confidence.  In fact, pessimism permeates most thinking on the subject; for as Wallace correctly reports, "the global scientific community is not currently giving this area sufficient attention."

So where is our attention currently focused?  Unfortunately, it is focused on reducing anthropogenic CO2 emissions to the atmosphere, which is truly lamentable; for the continuation of those emissions is, ironically, our only real hope for averting the near-certain future global food shortfall that is destined to occur if the Kyoto Protocol Crowd gets its way with the world.

But how would allowing anthropogenic CO2 emissions to take their natural course help to ameliorate future hunger?  The answer resides in the fact that elevated levels of atmospheric CO2 tend to reduce plant transpiration while simultaneously enhancing plant photosynthesis, which two phenomena enable earth's vegetation to produce considerably more food per unit of water used in the food production process.

Literally thousands of laboratory and field experiments - and that is no exaggeration - have verified this fact beyond any doubt whatsoever.  Indeed, this atmospheric CO2-derived blessing is as sure as death and taxes and as dependable as a mother's love.  But what do the climate-alarmist ideologues do about it?  They spurn it.  They deny it.  They try to reverse it, in fact.  And they do it to the detriment of all mankind.

So just how bad is the problem?  We're glad you asked, for we've asked the same question ourselves (see our Journal Review Will There Be Enough Food?).  And the answer, as we report in our Editorial of 15 November 2000, is yes, there will be enough, but just barely, and only if the CO2 content of the air is allowed to rise unimpeded by misguided attempts to curtail the burning of fossil fuels.

What we have found (Idso and Idso, 2000) is that likely advancements in agricultural technology and expertise will only increase world food production by about two-thirds of what will be required to feed the expected human population of the globe fifty years hence.  But if the air's CO2 content continues to rise as typically projected for "business as usual" scenarios, the aerial fertilization effect and the water use efficiency-promoting properties of the expected rise in atmospheric CO2 concentration will stimulate our crops to supply the final third of what will be required to meet our future dietary needs.

Even under the best of conditions, however, the match-up between future world food supply and demand will be so close as to leave extremely little room for ineptitude or error in our plans for supplying the various staples required by the planet's expanding human family.  Therefore, the Precautionary Principle - rightly applied (see our Editorial Prudence Misapplied) - demands we do everything possible to stave off the potential food insufficiency crisis our increasing numbers could well create fifty years from now.  And a crucial element of any policy devised to deal with this challenge must be to not interfere with the continuing evolution of earth's atmospheric CO2 concentration; for as described above, it is essential that the air's CO2 content continue to grow in the future as it has in the past.

In concluding this essay, we return to the writings of Wallace for some final words of wisdom.  "There can be," he says, "no greater global challenge today on which physical and social scientists can work together than the goal of producing the food required for future generations."  And in this regard, he notes that a "concerted focus on improving water use efficiency ... will increase the productivity of both rain fed and irrigated agriculture."  If this approach is taken, and if we do nothing unwise or counter-productive with respect to this effort, then, as Wallace states in his final sentence, "the prize is that more areas of the world, and especially those arid and semi-arid areas where population growth is greatest, will be able to sustain their future populations."

Truly, the long-term future of the planet's less-developed and poorer countries resides in the energy policies of the world's wealthier industrialized nations; and upon the decisions these nations will shortly make about anthropogenic CO2 emissions hangs the fate of the less-fortunate rest of the world.  It is imperative that the leaders of all nations wake up to the reality of what everyone is facing, especially the poorer resource-limited countries with high rates of population growth, and do the right thing.  Don't unduly strive to limit any nation's CO2 emissions.  It will only hurt us all.

Dr. Craig D. Idso
Dr. Keith E. Idso
Vice President

Notes and References
1. The special issue consists of papers presented at a conference of the Global Change and Terrestrial Ecosystems Core Project of the International Geosphere-Biosphere Program held at Reading, UK, in September 1999.

Idso, C.D. and Idso, K.E.  2000.  Forecasting world food supplies: The impact of the rising atmospheric CO2 concentration.  Technology 7S: 33-55.

Wallace, J.S.  2000.  Increasing agricultural water use efficiency to meet future food production.  Agriculture, Ecosystems & Environment 82: 105-119.