How does rising atmospheric CO2 affect marine organisms?

Click to locate material archived on our website by topic

Is There a Need for a More Sustainable Agriculture?
Volume 14, Number 24: 15 June 2011

In a paper that came to our attention a couple weeks ago, Gomiero et al. (2011) ask the question "Is there a need for a more sustainable agriculture?" This they do in the title of a paper recently published in Critical Reviews in Plant Sciences, where they write that "notwithstanding the great achievements of the 'Green Revolution,' the world will need 70 to 100% more food by 2050," concluding that "a new challenge lies ahead: how to feed nine billion with less land, water and energy, while at the same time preserving natural resources and soil fertility." Coincidentally, this is essentially the same question asked by one of us (Idso, 2011) in a major report published in the current week's issue of CO2 Science: "Estimates of Global Food Production in the Year 2050: Will We Produce Enough to Adequately Feed the World?"

In their analysis of the question, Gomiero et al. state that "technical advances are important in order to meet the future needs," as does Idso. In addition, Gomiero et al. state that "addressing key socioeconomic issues, such as the inequality in the access to resources, population growth and access to education are also a priority if we want to properly deal with sustainability." Idso alludes to these same factors, particularly population growth; but he concentrates most heavily on a subject not touched upon by Gomiero et al. -- the aerial fertilization effect of the ongoing rise in the air's CO2 content.

Idso first identifies the 45 key crops that account for 95% of world food production, after which he calculates the rates at which their productivities rose over the past 15 years in response to all technological innovations of that time period plus the concurrent increase in atmospheric CO2 concentration. Then, calculating the percentage increases in the productivities of these crops in response to a 300-ppm increase in the atmosphere's CO2 concentration from experimental data tabulated in the Plant Growth Database of CO2 Science, and knowing how much the atmosphere's CO2 content rose over the past 15 years, he determines what part of the past 15 years' productivity increases were due to the aerial fertilization effect of CO2 and what part was due to everything else, which remaining part he calls the techno-intel effect.

Extending the linear regression representing this latter effect to the year 2050, and using the IPCC's best median estimate of what the atmosphere's CO2 concentration will be in that year, Idso then calculates the productivity increases of the 45 key crops due to the aerial fertilization effect of CO2 to that point in time, adding the results to those he obtained for the techno-intel effect. This he does for the world as a whole, six world regions, twenty sub-regions and the 25 countries with the greatest populations. And comparing these results with what has been learned from the many different analyses of the subject -- and making adjustments for each geographic entity's projected rate of population growth -- he determines which entities' projected crop productivity increases fall either below, within or above the 70-100% interval that is deemed necessary to insure food security in 2050, with productivity increases below 70% representing food insecurity, with those above 100% representing food security, and with anything in between the two percentages being a "maybe" in terms of food security.

The results are rather chilling. And they should cause all those who are calling for mandatory reductions in anthropogenic CO2 emissions to seriously reconsider their views on the subject, while those who may not have thought at all about the topic should do so now; for the looming global food crisis is everybody's business, and all should have a say in what to do about it.

Sherwood, Keith and Craig Idso

Gomiero, T., Pimentel, D. and Paoletti, M.G. 2011. Is there a need for a more sustainable agriculture? Critical Reviews in Plant Sciences 30: 6-23.

Idso, C.D. 2011. Estimates of Global Food Production in the Year 2050: Will We Produce Enough to Adequately Feed the World? CO2 Science 14 (23).