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Agriculture (Our Greatest Challenge) -- Summary
Humanity faces many challenges; we always have, and we always will.  None of them, however, is as pressing as the need to be able to produce the food we will require to sustain ourselves in but a few short decades without usurping most of the planet's remaining arable land and freshwater resources in the process and thereby leaving precious little of either for the plant and animal components of the planet's natural ecosystems.  In addition, no need is more essential to the preservation of world peace than for people everywhere to have sufficient food to eat.

Many thoughtful people have agonized over these facts.  As described in our Editorial of 1 Oct 1999, for example, our local newspaper of 26 September 1999 published a brief article by former U.S. President Jimmy Carter entitled To cultivate peace, we must first cultivate food, wherein he stated that "when the Cold War ended 10 years ago, we expected an era of peace" but got instead "a decade of war."  He then asked why peace is so elusive, answering that most of today's wars are fueled by poverty - poverty in developing countries "whose economies depend on agriculture but which lack the means to make their farmland productive."  This fact, he said, suggests an obvious, but often overlooked, path to peace: "raise the standard of living of the millions of rural people who live in poverty by increasing agricultural productivity," his argument being that thriving agriculture, in his words, "is the engine that fuels broader economic growth and development, thus paving the way for prosperity and peace."

Can the case for atmospheric CO2 enrichment be made any clearer?  Automatically, and without investing a single hard-earned dollar, ruble or whatever, people everywhere promote the cause of peace when they utilize energy produced by the burning of fossil fuels; for CO2 - one of the major end-products of the combustion process - is the very elixir of life, being the primary building block of all plant tissues via the essential role it plays in the photosynthetic process that sustains nearly all of earth's vegetation.  And as with any production process, the insertion of more raw materials (in this case CO2) into the front of the production line results in more manufactured goods coming out the end of the line, which in the case of enhanced plant growth and development is biosphere-sustaining food.  Consequently, in light of the former president's statement that "leaders of developing nations must make food security a priority" for "there can be no peace until people have enough to eat," one can begin to appreciate the role of the ongoing rise in the air's CO2 content within this important context.

In investigating the subject in more detail, Idso and Idso (2000) developed a supply-and-demand scenario for food in the year 2050, wherein they identified the plants that currently supply 95% of the world's food needs and projected historical trends in their productivities (based on the assumption of continued increases in agricultural knowledge and expertise) 50 years into the future.  Under this scenario, they found that world food production would rise by about 37% between the start of the 21st century and its midpoint, but that world food needs, which they equated with world population, would likely rise by 51% over the same period.  Fortunately, they additionally calculated that the shortfall in production could be overcome (but only barely) by the benefits anticipated to accrue from the many productivity-enhancing effects of the expected concomitant rise in the atmosphere's CO2 concentration.

These findings demonstrate that world food security is precariously dependent upon the continued rising of the air's CO2 content, which must be allowed to take its natural course, for as Sylvan Wittwer, Director Emeritus of Michigan State University's Agricultural Experiment Station, stated in his 1995 book Food, Climate, and Carbon Dioxide: The Global Environment and World Food Production: "The rising level of atmospheric CO2 could be the one global natural resource that is progressively increasing food production and total biological output, in a world of otherwise diminishing natural resources of land, water, energy, minerals, and fertilizer.  It is a means of inadvertently increasing the productivity of farming systems and other photosynthetically active ecosystems.  The effects know no boundaries and both developing and developed countries are, and will be, sharing equally."

Also writing about the need to increase global food production near the close of the 20th century were the Rockefeller Foundation's Conway and Toenniessen (1999), who stated that "the Green Revolution was one of the great technological success stories of the second half of the twentieth century," but that its benefits were dropping and that a number of arguments "point to the need for a second Green Revolution."

It is enlightening to consider the arguments made by Conway and Toenniessen.  First, they note that the world already produces more than enough food to feed everyone on the planet, but that it is not evenly distributed, due to "notoriously ineffective" world markets that leave 800 million people chronically undernourished.  Hence, it would seem that requirement number one for the second Green Revolution should be that the agricultural benefits to be reaped should be equitably distributed among all nations.

Second, the Rockefeller representatives say that food aid programs designed to help countries most in need "are also no solution," as they reach "only a small portion of those suffering chronic hunger."  In addition, they say that such programs, if prolonged, "have a negative impact on local food production."  Hence, it would seem that requirement number two for the second Green Revolution should be that local food production should be enhanced worldwide.

Third, Conway and Toenniessen state that 650 million of the world's poorest people live in rural areas and that many of them live in "regions where agricultural potential is low and natural resources are poor."  Hence, it would seem that requirement number three for the second Green Revolution should be that regions of low agricultural potential lacking in natural resources should be singled out for maximum benefits.

All three of these requirements represent noble causes; but if mankind already produces more than enough food to feed everyone on the planet and we don't do it, i.e., we don't feed everyone, it is clear that mankind must not be noble enough to rise to the challenge currently confronting us.  So why does anyone think we will do any better in the future?  Based on humanity's prior track record, it would seem to us that the second Green Revolution envisioned by the Rockefeller Foundation will also fall short of its noble goal, depending, as it were, on a less-than-noble humanity to see it through.

So what do we do?  Let's consider the three requirements for the next Green Revolution and see how the likelihood of meeting them may be enhanced by letting the air's CO2 concentration continue to rise unimpeded.

Requirement No. 1: The agricultural benefits to be reaped should be equitably distributed among all nations.  First of all, what are the agricultural benefits of elevated atmospheric CO2?  For a 300 ppm increase in the air's CO2 content, they are 30 to 50% increases in the yields of nearly all food crops.  As for their equitable distribution among all nations, the fact that CO2 is well mixed throughout the atmosphere insures that all nations will share equally in the availability of this great resource and its proven yield-enhancing properties.

Requirement No. 2: Local food production should be enhanced worldwide.  The nice thing about the aerial fertilization effect of atmospheric CO2 enrichment in this regard is that it is a blessing that transcends all political barriers.  As Wittwer (1995) has so eloquently put it, the effects of elevated CO2 "know no boundaries and both developing and developed countries are, and will be, sharing equally," for "the rising level of atmospheric CO2 is a universally free premium, gaining in magnitude with time, on which we all can reckon for the foreseeable future."

Requirement No. 3: Regions of low agricultural potential lacking in natural resources should be singled out for maximum benefits.  Fortunately, CO2 helps most where people hurt most: in areas of low agricultural potential.  In a comprehensive review of the scientific literature, for example, Idso and Idso (1994) found that the greatest CO2-induced percentage increases in plant productivity typically occur in places of limited resources and heightened environmental stresses.

In light of these observations, it would seem that atmospheric CO2 enrichment meets the major requirements of the much-needed "second Green Revolution" as envisioned by the Rockefeller Foundation.  Their conventional programs will do much to help; but they will not solve the problem on their own.  With the ongoing rise in the air's CO2 concentration as a potent ally, however, we may come much closer to achieving our "noble goal" than we have ever come in the past.

Another perspective on the issue was provided by Norman Borlaug - father of the first Green Revolution and 1970 Nobel Prize Laureate for Peace - who had an important article entitled "Ending World Hunger: The Promise of Biotechnology and the Threat of Antiscience Zealotry" published in the October 2000 issue of Plant Physiology (Borlaug, 2000).  In it, he described the very real problem of potential food shortages that could be faced by the world in but a couple of decades.  Noting that "it took some 10,000 years to expand food production to the current level of about 5 billion tons per year," he wrote that in order to meet the needs of the planet's growing population by only 2025, "we will have to nearly double current production again."  Unfortunately, he saw some ominous forces at work that could keep us from achieving that goal.

The counter-productive forces Borlaug identified are those that array themselves against the new techniques of biotechnology, specifically, against the genetic engineering of agricultural crops.  "Extremists in the environmental movement," he says, "seem to be doing everything they can to stop scientific progress in its tracks."  The legendary Peace Prize winner states, for example, that "the platform of the antibiotechnology extremists, if it were to be adopted, would have grievous consequences for both the environment and humanity," and he laments that "some scientists, many of whom should or do know better, have also jumped on the extremist environmental bandwagon in search of research funds."

What strikes us most forcefully about Dr. Borlaug's words is how they also describe the sad situation we face with respect to the ongoing rise in the air's CO2 concentration.  He talks, for example, about the "unsubstantiated scare mongering done by opponents of genetic engineering," which is amazingly similar to the unsubstantiated scare mongering done by climate alarmists, who would deny the world the incredible agricultural benefits of the aerial fertilization effect of atmospheric CO2 enrichment.  "Nowhere," Dr. Borlaug says, "is it more important for knowledge to confront fear born of ignorance than in the production of food," which is what we have been endeavoring to do on our website from the day it first went public.

It is truly unconscionable that this agricultural aspect of the global change debate is almost never broached.  As Dr. Borlaug rightly states, "agricultural scientists and leaders have a moral obligation to warn political, educational, and religious leaders about the magnitude and seriousness of the arable land, food, and population problems that lie ahead, even with breakthroughs in biotechnology [our italics]."  In fact, "if we fail to do so," he says, "we will be negligent in our duty and inadvertently may be contributing to the pending chaos of incalculable millions of deaths by starvation."

In addition to impending food shortages, we face the problem of impending water shortages.  Wallace (2000) illustrates the source and magnitude of the problem by noting that the projected increase in the number of people who 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 on the horizon; and these extra people will need a whopping amount of extra food that will take an equally whopping amount of extra water to produce, the problem being that there is no extra water.  "Over the entire globe," therefore, says Wallace, "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 and war.

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 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 and water shortfalls that are 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 thirst as well as 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 acting together enable earth's crops to produce more food per unit of water used in the 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-induced blessing is as sure as death and taxes, and as dependable as a mother's love.  But what do climate-alarmist ideologues do about it?  They spurn it.  They deny it.  They even try to make people believe the opposite (see our Editorial of 13 Dec 2000).  And they do it to the detriment of all mankind.

In concluding his analysis, Wallace says "there can be 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 the effort (such as trying to reduce anthropogenic CO2 emissions), 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."

In light of the many significant problems we face in attempting to produce the food we will need to sustain ourselves in the not too distant future, one may well wonder, as did Waggoner (1995): "How much land can ten billion people spare for nature?"

As noted by Huang et al. (2002), human populations "have encroached on almost all of the world's frontiers, leaving little new land that is cultivatable."  And in consequence of humanity's ongoing usurpation of this most basic of natural resources, Raven (2002) notes that "species-area relationships, taken worldwide in relation to habitat destruction, lead to projections of the loss of fully two-thirds of all species on earth by the end of this century."

If one were to pick the most significant problem currently facing the biosphere, this would probably be it: a single species of life, Homo sapiens, is on course to completely annihilate fully two-thirds of the ten million or so other species with which we share the planet within a mere hundred years, simply by taking their land.  Global warming, by comparison, pales in significance.  Its impact is nowhere near as severe, being possibly nil or even positive.  In addition, its root cause is highly debated; and actions to thwart it are much more difficult, if not impossible, to both define and implement.  Furthermore, what many people believe to be the cause of global warming, i.e., anthropogenic CO2 emissions, may actually be a powerful force for preserving land for nature.

What parts of the world are likely to be hardest hit by the human land-eating machine?  As described in our Editorials of 2 May 2001 and 13 June 2001, Tilman et al. (2001) note that developed countries are expected to actually withdraw large areas of land from cultivation over the next 50 years, leaving developing countries to shoulder essentially all of the burden of feeding the growing numbers of our species.  In addition, they calculate that the loss of these countries' natural ecosystems to cropland and pasture will amount to about half of all potentially suitable remaining land, which "could lead to the loss of about a third of remaining tropical and temperate forests, savannas, and grasslands," along with the many unique species of both plants and animals that they support, which scenario has also been discussed by Pretty et al. (2003).

What can be done to alleviate this bleak situation?  In another analysis of the problem, Tilman et al. (2002) introduce a few more facts before suggesting some solutions.  They note, for example, that by 2050 the human population of the globe is projected to be 50% larger than it is today and that global grain demand could well double, due to expected increases in per capita real income and dietary shifts toward a higher proportion of meat.  Hence, they but state the obvious when they conclude that "raising yields on existing farmland is essential for 'saving land for nature'."

So how is it to be done?  Tilman et al. (2002) suggest a strategy that is built around three essential tasks: (1) increasing crop yield per unit of land area, (2) increasing crop yield per unit of nutrients applied, and (3) increasing crop yield per unit of water used.

With respect to the first of these requirements, Tilman et al. note that in many parts of the world the historical rate of increase in crop yields is declining, as the genetic ceiling for maximal yield potential is being approached.  This observation, they say, "highlights the need for efforts to steadily increase the yield potential ceiling."  With respect to the second requirement, they note that "without the use of synthetic fertilizers, world food production could not have increased at the rate it did [in the past] and more natural ecosystems would have been converted to agriculture."  Hence, they say the ultimate solution "will require significant increases in nutrient use efficiency, that is, in cereal production per unit of added nitrogen, phosphorus," and so forth.  Finally, with respect to the third requirement, Tilman et al. note that "water is regionally scarce," and that "many countries in a band from China through India and Pakistan, and the Middle East to North Africa either currently or will soon fail to have adequate water to maintain per capita food production from irrigated land."  Increasing crop water use efficiency, therefore, is also a must.

Although the impending biological crisis and several important elements of its potential solution are thus well defined, Tilman et al. (2001) report that "even the best available technologies, fully deployed, cannot prevent many of the forecasted problems."  However, we have a powerful ally in the ongoing rise in the atmosphere's CO2 concentration that can provide what we can't.  For a nominal doubling of the air's CO2 content, for example, the productivity of earth's herbaceous plants rises by 30 to 50% (Kimball, 1983; Idso and Idso, 1994), while the productivity of its woody plants rises by 50 to 80% (Saxe et al. 1998; Idso and Kimball, 2001).  Hence, as the air's CO2 content continues to rise, so too will the land use efficiency of the planet rise right along with it.  In addition, atmospheric CO2 enrichment typically increases plant nutrient use efficiency and plant water use efficiency (see Nitrogen Use Efficiency and Water Use Efficiency in our Subject Index).  Thus, with respect to all three of the major needs noted by Tilman et al. (2002), increases in the air's CO2 content pay huge dividends, helping to increase agricultural output without the taking of land away from nature.

In conclusion, it would appear that the extinction of two-thirds of all species of plants and animals on the face of the earth is essentially assured within the next century, unless world agricultural output is dramatically increased.  This unfathomable consequence hangs over us simply because we will need more land to produce what is required to sustain ourselves and, in the absence of the needed productivity increase, because we will simply take land from nature to keep ourselves alive.  It is also the conclusion of scientists who have studied this problem in depth that the needed increase in agricultural productivity is not possible, even with anticipated improvements in technology and expertise.  With the help of the ongoing rise in the air's CO2 content, however, we should be able - but just barely - to meet our expanding food needs without bringing down the curtain on the world of nature.

That certain forces continue to resist this reality is truly incredible.  More CO2 means life for the planet; less CO2 means death ... and not just the death of individuals, but the death of species.  And to allow, nay, to cause the extinction of untold millions of unique plants and animals has got to rank close to the top of all conceivable immoralities.

We humans, as stewards of the earth, have got to get our priorities straight by getting our facts straight.  We have got to do all that we can to preserve nature by helping to feed humanity; and to be successful, we have got to let the air's CO2 content rise.  Any policies that stand in the way of that objective are truly obscene.

Borlaug, N.E.  2000.  Ending world hunger. The promise of biotechnology and the threat of antiscience zealotry.  Plant Physiology 124: 487-490.

Conway, G. and Toenniessen, G.  1999.  Feeding the world in the twenty-first century.  Nature 402 Supp: C55-C58.

Huang, J., Pray, C. and Rozelle, S.  2002.  Enhancing the crops to feed the poor.  Nature 418: 678-684.

Idso, C.D. and Idso, K.E.  2000.  Forecasting world food supplies: The impact of the rising atmospheric CO2 concentration.  Technology 7S: 33-56.

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. and Kimball, B.A.  2001.  CO2 enrichment of sour orange trees: 13 years and counting.  Environmental and Experimental Botany 46: 147-153.

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Tilman, D., Fargione, J., Wolff, B., D'Antonio, C., Dobson, A., Howarth, R., Schindler, D., Schlesinger, W.H., Simberloff, D. and Swackhamer, D.  2001.  Forecasting agriculturally driven global environmental change.  Science 292: 281-284.

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Wittwer, S.H.  1995.  Food, Climate, and Carbon Dioxide: The Global Environment and World Food Production.  CRC Press, Boca Raton, FL.

Last updated 11 January 2006