[Illustrations, footnotes and references available in PDF version]
Advancements in technology and scientific expertise that accompanied the Industrial Revolution initiated a great transformation within the global enterprise of agriculture. More efficient machinery and improved plant cultivars, for example, paved the way toward higher crop yields and increased global food production. And with the ever-burgeoning population of the planet, the increase in food production was a welcomed societal benefit. But what remained largely unknown to society at that time, was the birth of an ancillary aid to agriculture that would confer great benefits upon future inhabitants of the globe in the decades and centuries to come. The source of that aid: atmospheric carbon dioxide (CO2).
For a 300-ppm increase in the air’s CO2 content, such benefits typically enhance herbaceous plant biomass by around 30 to 35%, which represents an important positive externality entirely absent from today’s state-of-the-art SCC calculations.
And as the CO2 concentration of the air continues to rise in the future, this positive externality of enhanced crop production will benefit society in the years, decades, and even centuries to come.
A somewhat related problem with SCC calculations is their inclusion of costs due to sea level rise. Here, it is presumed that rising temperatures from CO2-induced global warming will result in an acceleration of sea level rise that will bring on a host of economic damages. There are two problems with this projection. First, temperatures are not rising in the manner or degree projected by the models. Second, observations reveal no acceleration of sea level rise over the past century. In fact, just the opposite appears to be occurring in nature.
Holgate (2007), for example, derived a mean global sea level history over the period 1904-2003. According to their calculations, the mean rate of global sea level rise was “larger in the early part of the last century (2.03 ± 0.35 mm/year 1904-1953), in comparison with the latter part (1.45 ± 0.34 mm/year 1954-2003).” In other words, contrary to model projections, the mean rate of global sea level rise (SLR) has not accelerated over the recent past. If anything, it’s done just the opposite. Such observations are striking, especially considering they have occurred over a period of time when many have claimed that (1) the Earth warmed to a degree that is unprecedented over many millennia, (2) the warming resulted in a net accelerated melting of the vast majority of the world’s mountain glaciers and polar ice caps, and (3) global sea level rose at an ever increasing rate.
In another paper, Boretti (2012) applied simple statistics to the two decades of information contained in the TOPEX and Jason series of satellite radar altimeter data to “better understand if the SLR is accelerating, stable or decelerating.” In doing so, the Australian scientist reports that the rate of SLR is reducing over the measurement period at a rate of -0.11637 mm/year2, and that this deceleration is also “reducing” at a rate of -0.078792 mm/year3 (see Figure 7). And in light of such observations, Boretti writes that the huge deceleration of SLR over the last 10 years “is clearly the opposite of what is being predicted by the models,” and that “the SLR’s reduction is even more pronounced during the last 5 years.” To further illustrate the importance of his findings, he notes that “in order for the prediction of a 100-cm increase in sea level by 2100 to be correct, the SLR must be almost 11 mm/year every year for the next 89 years,” but he notes that “since the SLR is dropping, the predictions become increasingly unlikely,” especially in view of the facts that (1) “not once in the past 20 years has the SLR of 11 mm/year ever been achieved,” and that (2) “the average SLR of 3.1640 mm/year is only 20% of the SLR needed for the prediction of a one meter rise to be correct.”
The real-world data-based results of Holgate and Boretti, as well as those of other researchers (Morner, 2004; Jevrejeva et al., 2006; Wöppelmann et al., 2009; Houston and Dean, 2011), all suggest that rising atmospheric CO2 emissions are exerting no discernible influence on the rate of sea level rise. Clearly, SCC damages that are based on model projections of a CO2-induced acceleration of SLR must be considered inflated and unlikely to occur.
It is clear from the material presented in this report that the modern rise in the air’s CO2 content is providing a tremendous economic benefit to global crop production. As Sylvan Wittwer, the father of agricultural research on this topic, so eloquently put it nearly two decades ago:
“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,” 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” (Wittwer, 1995).
The relationship described above by Wittwer is illustrated below in Figure 8, where data pertaining to atmospheric CO2 emissions, food production, and human population are plotted. Standardized to a value of unity in 1961, each of these datasets has experienced rapid and interlinked growth over the past five decades. Rising global population has led to rising CO2 emissions and rising CO2 emissions have benefited food production. The very real positive externality of inadvertent atmospheric CO2 enrichment must be considered in all studies examining the SCC; and its observationally-deduced effects must be given premier weighting over the speculative negative externalities presumed to occur in computer model projections of global warming. Until that time, little if any weight should be placed on current SCC calculations.
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