Rupert Darwall: Why the IPCC Report Neglects the Benefits of Global Warming

Posted: April 2, 2014 by tallbloke in alarmism, climate, propaganda

Repost from

Why the IPCC Report Neglects the Benefits of Global Warming 
It needs catastrophe scenarios. 


josh_raymondo_scrThe IPCC’s Working Group II, tasked with assessing the risks and impacts of climate change, could have chosen to make amends for its previous effort in 2007, which was widely panned for bias and numerous errors. Such was the outcry over the 2007 report that the Dutch parliament ordered the country’s Environmental Assessment Agency to carry out an audit. It found that the working group was dismissive of the potential benefits of climate change, and it criticized the group’s process for being insufficiently transparent. Similarly, a report by the InterAcademy Council, chaired by Princeton’s Harold Shapiro, noted that the group’s Summary for Policymakers had been criticized “for various errors and for emphasizing the negative impacts of climate change.” The summary contained many statements that “are not supported sufficiently in the literature, not put into perspective, or not expressed clearly,” the Council said.

The summary, as the object of intensive political editing by government officials, is a document designed to generate talking points for sympathetic politicians and pundits to re-spin. Scientific coherence is not its goal. Instead of raising the bar in pursuit of objectivity, the current working group doubled down on its 2007 summary: It unfurls a series of distortions designed to magnify the threats, ignore the benefits, and downplay the possibility of adapting to climate change.

Its most eye-catching claim is that negative impacts of climate change on crop yields are more common to date than positive impacts are. This improbable claim finds only the weakest support in the main body of the report, with its qualification that climate change played a “minor role.” It is, the report states, “extremely difficult” to define a clear baseline from which to assess the impact of climate change, and many non-climate factors are often difficult to quantify.

More egregiously, the summary speaks of rapid price increases following climate extremes since the 2007 report. This negligence amounts to downright dishonesty, as the summary omits mention of one of the principal causes of the 2007–08 spike in food prices, which is highlighted in the main body of the report. It was not climate change that increased food costs, but climate policies in the form of increased use of food crops in biofuel production, exacerbated by higher oil prices and government embargoes on food exports.

In attempting to attribute changes in farm output to climate change, the IPCC makes heavy use of models linking climate to agriculture, most of which assume that farmers don’t change their behavior as the climate changes. Instead of relying on speculative models based on the condescending assumption that farmers are robots and don’t adapt, a more intelligent approach would be to examine how farmers and agricultural output have reacted to climate change in the past. But the IPCC rendered this approach impossible when it erased previous periods during which temperatures might have been higher than they are now (symbolized by the Hockey Stick in the IPCC’s 2001 report). In 2005, Jonathan Overpeck, one of the drafting authors of the 2014 summary, e-mailed a colleague, saying he intended to “deal a mortal blow” to the supposed “misuse” of the Medieval Warm Period in the 2007 report. Overpeck succeeded in his aim of getting rid of the Medieval Warm Period.

A feature of the Working Group II is that it is dominated by by natural scientists, led by Chris Field, a biologist from Stanford. “It is true we couldn’t find very many benefits of climate change,” Field told the Financial Times. “We worked really, really hard to identify every benefit we could find.” But not that hard. As journalist Matt Ridley wrote in the Wall Street Journal in January 2013 on the greening of the planet, analysis of satellite data shows that between 1982 and 2011, 20.5 percent of the world’s vegetated area got greener, while just 3 percent grew browner; the most likely causes are higher temperature, higher levels of carbon dioxide, or both.

Of the 71 authors of the summary, only three are economists; of these, one did not engage in work on the summary for the last two years; and one, Richard Tol, insisted his name be removed from the summary because it is, as he put it, too alarmist and it makes silly claims. The IPCC’s own analysis suggests that a warming of 2 degrees Celsius could cause losses equivalent to 0.2–2 percent of world gross domestic product. Climate change is not, Tol says, humanity’s biggest problem. Nor is it even our biggest environmental problem.

In 1972, the British government appointed an environmental commission chaired by a botanist that produced a report entitled “Pollution: Nuisance or Nemesis?” The majority, comprising scientists, thought civilization was facing nemesis. The minority, led by the economist Wilfred Beckerman, opted for nuisance. Two years later, Beckerman wrote of his experience on the commission, observing that scientists “do not have a minimal understanding of the way that the world of human beings operates.” As the IPCC has shown this week, plus ça change.

— Rupert Darwall is the author of The Age of Global Warming: A History.

Read the full article

  1. michael hart says:

    In 2006, even the Guardian understood that tripling the CO2 concentration in greenhouses increased crop production.
    I was first taught about plants needing carbon dioxide for photosynthesis in infant school. What does this say about the IPCC?

    The even bigger clue is in the word “greenhouse”. We build them to keep plants warm. They like it.

  2. oldbrew says:

    IPCC ‘needs catastrophe scenarios’

    They could have claimed their ‘climate change’ would make triffids more likely 😉

  3. “but it is only a trace gas and so cannot have an effect” so you say
    but now you say a trace gas will cause plants to grow.

    I think you will find this applies to some not all, plants. And I think you’ll find it does not necessarily increase crop quality:
    “CO2 and Wheat: How We Get Less Protein, More Sugar
    Without question, wheat is a staple crop. With the help of corn and rice, wheat provides about 60 percent of the world’s food. Therefore, how wheat responds to enhanced CO2 is a big deal, and FACE study results (for example here and here) are not encouraging: while wheat yields increase, its protein content drops.”

  4. flaxdoctor says:


    Your link is self-contradictory and seeks to disinform.

    I can tell you with absolute confidence that the protein content of wheat DOES NOT DROP as yields increase due to increased CO2 as observed in FACE experiments – what MAY happen is that starch accumulation may increase slightly more rapidly than protein, thereby slightly reducing protein CONCENTRATION. So you might get 15 tonnes per hectare at 12.0% protein with CO2 enrichment rather than 12 tonnes per hectare at 12.3% protein at atmospheric CO2 levels. This is of course a routine challenge for plant breeders.

    And whilst starch might be made of glucose molecules, it’s no more ‘sugar’ than is cellulose. Fructans likewise – in case you’re unaware, these are sometimes marketed as ‘prebiotics’ – they’re beneficial in the diet.

  5. ren says:

    Meanwhile, the winter in North America will not forgive. Because of the cold soil sowing crops will be delayed.,92.82,482

  6. Kon Dealer says:

    And just what Global Temperature do the cretins in the IPCC think is best?

    That 200 years ago?
    At the Holocene Optimum?
    In the middle of the last Ice Age?

    The Earth’s bioproductivity at these different times should give these numpties a clue.

  7. Kon Dealer says:

    thefordfrefect is taking bollocks.
    I have a PhD in plant physiology (Cambridge University) so I know a little bit about photosynthesis, effects of CO2 etc.

  8. The ground work is now being put in place for cooling going forward, not warming as the IPCC keeps insisting on.

    PDO cold phase
    AMO will be in cold phase
    SOLAR sub activity will lessen going forward.
    MAGNETIC FIELD weakening going forward.
    MILANKOVITCH CYCLES favorable overall for cooling.

    VOLCANIC ACTIVITY /COSMIC RAYS/CLOUDS/MERIDIONAL ATMOSPHERIC CIRCULATION / PRECIPITATION/SNOW COVER/ ALBEDO–all likely to increase going forward as a result of very weak prolonged solar conditions all of which will promote cooling.

    While as less energy comes into the climate system via the sun the greenhouse gas effect will weaken in response, and ocean heat content will lessen again promoting cooling. .

    Everything is in place for cooler temperatures going forward.

  9. tom0mason says:

    The NIPCC report does a much better job. ( ) A lot less scary and more based on real world measurements,events, and more sober outcomes.

    I note that both reports (NIPCC and the UN-IPCC) assume a warming future after the pause. It will be unfortunate if the opposite happens and we are left scrambling to keep-up with nature’s change of mind.

  10. Effects of elevated CO2 and nitrogen on wheat growth and photosynthesis
    Division of Plant Physiology, Indian Agricultural Research Institute, New Delhi, India
    The effects of nitrogen [75 and 150 kg (N) ha-1] and elevated CO2 on growth, photosynthetic rate, contents of soluble leaf proteins and activities of ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) and nitrate reductase (NR) were studied on wheat (Triticum aestivum L. cv. HD-2285) grown in open top chambers under either ambient (AC) or elevated (EC) CO2 concentration (350 ± 50, 600 ± 50 μmol mol-1) and analyzed at 40, 60 and 90 d after sowing. Plants grown under EC showed greater photosynthetic rate and were taller and attained greater leaf area along with higher total plant dry mass at all growth stages than those grown under AC. Total soluble and Rubisco protein contents decreased under EC but the activation of Rubisco was higher at EC with higher N supply. Nitrogen increased the NR activity whereas EC reduced it. Thus, EC causes increased growth and PN ability per unit uptake of N in wheat plants, even if N is limiting.

    [Reply] Since the reduction in protein is per unit mass, but the mass is increasing, I won’t worry too much about this. – TB.

  11. Effects of elevated CO2 on the protein concentration of food crops: a meta-analysis
    Meta-analysis techniques were used to examine the effect of elevated atmospheric carbon dioxide [CO2] on the protein concentrations of major food crops, incorporating 228 experimental observations on barley, rice, wheat, soybean and potato. Each crop had lower protein concentrations when grown at elevated (540–958 μmol mol−1) compared with ambient (315–400 μmol mol−1) CO2. For wheat, barley and rice, the reduction in grain protein concentration was ∼10–15% of the value at ambient CO2. For potato, the reduction in tuber protein concentration was 14%. For soybean, there was a much smaller, although statistically significant reduction of protein concentration of 1.4%. The magnitude of the CO2 effect on wheat grains was smaller under high soil N conditions than under low soil N….

    [Reply] Humans might get bigger having to eat bigger plants to obtain the same amount of protein then. At least we won’t get lost in the wheat forests. Lol. – TB.

  12. Cassava is an important food for millions of people in Africa, Asia, and Latin America. When grown in conditions of increased CO2, however, its cyanide levels jump.
    The effects of nitrogen [75 and 150 kg (N) ha-1] and elevated CO2 on growth, photosynthetic rate, contents of soluble leaf proteins and activities of ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) and nitrate reductase (NR) were studied on wheat (Triticum aestivum L. cv. HD-2285) grown in open top chambers under either ambient (AC) or elevated (EC) CO2 concentration (350 ± 50, 600 ± 50 μmol mol-1) and analyzed at 40, 60 and 90 d after sowing. Plants grown under EC showed greater photosynthetic rate and were taller and attained greater leaf area along with higher total plant dry mass at all growth stages than those grown under AC. Total soluble and Rubisco protein contents decreased under EC but the activation of Rubisco was higher at EC with higher N supply. Nitrogen increased the NR activity whereas EC reduced it. Thus, EC causes increased growth and PN ability per unit uptake of N in wheat plants, even if N is limiting.

    [Reply] “Cyanide levels jump” from harmless trace to … harmless trace. Like co2. Eggs contain arsenic too Nice try at scaremongering though – TB. 🙂

  13. […] April 3, 2014 at 2:20 am […]

  14. Kon Dealer says:

    In a recent analysis of 159 peer-reviewed scientific journal articles published between 1983 and 2000, dealing with the effects of atmospheric CO2 enrichment on the reproductive growth characteristics of several domesticated and wild plants, Jablonski et al. (2002) calculated some interesting mean responses. For increases in the air’s CO2 concentration ranging from approximately 150 to 450 ppm (rough average of 300 ppm), they found that, across all species studied, the extra CO2 supplied to the plants resulted in more flowers (+19%), more fruits (+18%), more seeds (+16%), greater individual seed mass (+4%), greater total seed mass (+25%, equivalent to yield), and greater total mass (+31%).
    Normally, these findings would have been heralded as great news; but there was another – seemingly negative – finding that assumed center stage in subsequent discussions of the paper: mean seed nitrogen concentration across all of the species studied decreased by 14%, which Jablonski et al. equated with a similar decrease in seed protein content.

    The negative spin began with a report that was posted on the Ohio State Research News website on 2 October 2002. Entitled “Increased CO2 Levels Are Mixed Blessing for Agriculture,” it quoted one of the study’s authors – Peter Curtis, a professor at Ohio State University – as saying that, “while crops may be more productive,” when growing in air enriched with CO2, “the resulting produce will be of lower nutritional quality.”

    As early as the next day, Environment News Service was trumpeting “More Carbon Dioxide Could Reduce Crop Value,” while on 7 October Reuters joined the act with “Global Warming Boosts Crops, Cuts Nutrients.” And as surely as night follows day, global-change websites quickly began to chat up the alleged bad news.

    Curtis’s statement that “while crops may be more productive, the resulting produce will be of lower nutritional quality” in a future high-CO2 world. This claim is simply false; but it could be corrected by merely interchanging its two verbs, so that the statement reads “while crops will be more productive, the resulting produce may be of lower nutritional quality.” In fact all of the food crops studied by Jablonski et al. (rice, soybean, barley, wheat and maize) were more productive when exposed to elevated concentrations of atmospheric CO2, while only two of them (barley and wheat) exhibited decreases in seed nitrogen content under such conditions.

    The most-benefited of the studied crops, exhibiting a whopping 42% increase in seed number as a consequence of atmospheric CO2 enrichment, was rice, which according to Wittwer (1995) is “the basic food for more than half the world’s population.” It is particularly noteworthy that this incredibly important crop did not exhibit any decrease in seed nitrogen content in CO2-enriched air, which is a most wonderful result. Indeed, in the case of this basic food crop, upon which over half the human population of the planet depends for its very existence, it is as if the carbon dioxide we emit to the atmosphere as a consequence of our industrial activities comes back to us as unadulterated manna from heaven.

    Likewise, there were no decreases in the seed nitrogen contents of any of the legumes studied by Jablonski et al. Wittwer reports that legumes provide fully 20% of the protein that is ingested by humans throughout the world. In addition, he notes that “the soybean alone provides about two thirds of the world’s protein concentrate for livestock feeding, and is a valuable ingredient in formulated feeds for poultry and fish.” Hence, it can be appreciated that the ongoing rise in the air’s CO2 content will not adversely affect protein contents in the legume-based sectors of the human and animal food industries either.

    But what about the CO2-induced seed nitrogen content decreases reported by Jablonski et al. for barley and wheat? I do not deny that such decreases have been observed. However, it has been convincingly demonstrated by Rogers et al. (1996), Pleijel et al. (1999) and Kimball et al. (2001) that higher levels of nitrogen fertilizer application have the capacity to totally offset this negative impact of atmospheric CO2 enrichment (Idso and Idso, 2001), so that with proper crop husbandry there need be no reductions in either grain nitrogen or protein contents, or in the baking properties of flour derived from the grains of those crops.

  15. [Reply] “Cyanide levels jump” from harmless trace to … harmless trace. Like co2. Eggs contain arsenic too Nice try at scaremongering though – TB

    Doesn’t sound like a harmless trace to me!:

    ….Sweet cassava roots can generally be made safe to eat by peeling and thorough cooking. However, bitter cassava roots require more extensive processing. One of the traditional ways to prepare bitter cassava roots is by first peeling and grating the roots, and then prolonged soaking of the gratings in water to allow leaching and fermentation to take place, followed by thorough cooking to release the volatile hydrogen cyanide gas. Cutting the roots into small pieces, followed by soaking and boiling in water is particularly effective in reducing the cyanide content in cassava. Whilst fresh cassava requires traditional methods to reduce its toxicity, adequately processed cassava flour and cassava-based products have very low cyanide contents and are considered safe to use….

  16. Kon Dealer says:
    April 3, 2014 at 11:40 am

    If I buy 1kg of low CO2 grain at £z I get x amount of protein
    If I buy 1kg of High CO2 grain probably at £z I get x*0.9 amount of protein.and more carbohydrate

    Or I could buy High CO2 grain grown with more fertiliser at £z*y (y greater than 1) and get what I was getting at current CO2 levels

    Which makes more sense to impoverished people?

    In UK grain crops have been selected to have short sturdy stems (compared to 60s) to ensure they remain standing at harvest time. Taller, leafier plants will reverse that selection + they will attempt to take more nitrogen from the soil.
    Perhaps straw thatching will become fashionable?

    Having had nothing to do with biological science since gcse’s I can only quote others and this does not seem like no reduction in grain protein in rice:

    (from 2013)
    The effects of free-air CO2 enrichment (FACE) on carbon and
    nitrogen accumulation in grains of rice (Oryza sativa L.)
    Rising atmospheric CO2 concentrations will probably increase rice (Oryza sativa L.) yield but decrease grain nitrogen (GN) concentration. Grains attached to different positions in the anicles differ greatly in weight and quality, but their responses to elevated CO2 (e[CO2]) are poorly understood, which limits our understanding of the mechanisms of yield enhancement and quality degradation. Thus a free-air CO2 enrichment experiment was conducted to examine the
    effects of e[CO2] on grain mass (GM), grain carbon (GC), and GN accumulation in the spikelets attached to the upper primary rachis branch (superior spikelets; SS) and those attached to the lower secondary rachis (inferior spikelets;IS). e[CO2] stimulated the rice yield by 13% but decreased the N concentration in the panicle by 7% when averaged over two levels of N fertilizations (P < 0.01). The responses of SS and IS to e[CO2] were different particularly under
    higher N supply. For SS, e[CO2] decreased GN by 24% (P < 0.01) but did not affect GM. For IS, e[CO2] increased GM by 13% (P < 0.05) but GN was not affected. The reduction of GN due to e[CO2] started to appear at the beginning of grain filling. These results suggest that future [CO2] levels probably stimulate the grain growth of IS, most of which are not marketable due to limited size, at the expense of GN reduction in SS. Translocation of N from SS to IS may be a possible mechanism for reduction in GN of SS. This may degrade the grain quality of marketable rice under e[CO2].

  17. Kon Dealer says:

    thefordprefect says “Having had nothing to do with biological science since gcse’s I can only quote others”
    Typical green- no understanding of the science.

  18. Kon Dealer says:
    April 3, 2014 at 7:23 pm
    thefordprefect says “Having had nothing to do with biological science since gcse’s I can only quote others”
    Typical green- no understanding of the science.


    Hold on mate, I know quite a lot of science/electronics/software I was simply pointing out that I have not researched this field before, whereas you seemed to write lots of stuff as if you were the source (i.e. no references). I understand the text I printed. I do not know the physics/chemistry/genetics/biology behind their research!!

  19. Gail Combs says:

    tom0mason says: @ April 2, 2014 at 11:36 pm

    I note that both reports (NIPCC and the UN-IPCC) assume a warming future after the pause. It will be unfortunate if the opposite happens and we are left scrambling to keep-up with nature’s change of mind.
    Everyone keeps ignoring geology and WHEN we are. William McClenney. a geologist, has been tracking papers in Quaternary science for years and is very well read on the subject. He makes several unsettling points one of which is he has seen no papers on an extended Holocene interglacial since the Lisiecki and Raymo’s 2005 rebuttal soundly trounced the Loutre and Berger’s 2003 astronomical model.

    In his words:
    1. Is the Holocene interglacial, our interglacial, just about kaput? Well, that’s the trillion dollar question, isn’t it? The present consensus seems to be that we will not have an extended interglacial this time.

    2. So, tipping points. Based on the end of the Younger Dryas, the Holocene this year is 11,715 years old. We are at the long end of the precession cycle at 23,000 years, so, eerily close to half a precession cycle old right now. Onset of the Little Ice Age after the Medieval Warm Period, right when the Holocene reached about half a precession cycle old, was harrowing enough. The Modern Warm Period, reportedly less warm then the MWP, marks the second thermal pulse, a few centuries older than half a precession cycle, and still within the Holocene. (…there were two [thermal pulses] in MIS-11 [before glaciation]…)

    3. Aside from Loutre and Berger’s 2003 astronomical model, which was soundly trounced by Lisiecki and Raymo’s 2005 rebuttal, there has only been one well-accepted means of preventing glacial inception discussed in the literature: greenhouse gases. This, of course, is not how it is meant to be discussed in the “new science.” Can anyone suggest another means of delaying or preventing glacial inception except GHGs?

    4. Five of the 6 interglacials dating back to the Mid Pleistocene Transition have each lasted just half of a precessional cycle. If you warmists are right, you just plunked-down on MIS-1 repeating the extended interglacial MIS-11, for however long you fancy. Please do note, however, that MIS-11 was not all that stable a climate ride………:

    Even during the only post-MPT interglacial to make it past about half a precession cycle it got awfully cold between MIS-11′s two insolation peaks.
    And lastly Williams says:
    Let’s try getting there from an entirely different perspective. Lisiecki and Raymo (Paleooceanography, 2005) produced an exhaustive analysis of 57 globally distributed deep ocean cores reaching back about 5 million years. The widely referenced LR05 stack in the literature since suggests that this is a landmark paper in paleoclimate science. One passage from this thorough analysis will suffice:

    “Recent research has focused on MIS 11 as a possible analog for the present interglacial [e.g., Loutre and Berger, 2003; EPICA community members, 2004] because both occur during times of low eccentricity. The LR04 age model establishes that MIS 11 spans two precession cycles, with 18O values below 3.6o/oo for 20 kyr, from 398-418 ka. In comparison, stages 9 and 5 remained below 3.6o/oo for 13 and 12 kyr, respectively, and the Holocene interglacial has lasted 11 kyr so far. In the LR04 age model, the average LSR of 29 sites is the same from 398-418 ka as from 250-650 ka; consequently, stage 11 is unlikely to be artificially stretched. However, the June 21 insolation minimum at 65N during MIS 11 is only 489 W/m2, much less pronounced than the present minimum of 474 W/m2. In addition, current insolation values are not predicted to return to the high values of late MIS 11 for another 65 kyr. We propose that this effectively precludes a ‘double precession-cycle’ interglacial [e.g., Raymo, 1997] in the Holocene without human influence.”

    This is the perspective. The summer solstice insulation minimum during MIS-11 at 65N was 489 Watt/m2 and it was 474 Watt/m2 in ~2005 (Lisiecki and Raymo, 2005). You need 15 Watt/m2 to get to the insolation minimum in MIS-11. I am not familiar with any CO2 estimates which correlate with a 15 Watt/m2 rise in atmospheric forcing.

    …The vast research I have done attempting to ferret out whatever is available on the last several ice ages and interglacials, especially the transitions, suggests that the single greatest mystery in all of climate science is what causes abrupt climate change in the absence of hominid emissions. Evidence for D-O oscillations extends as far back as 680 million years in varves found in lacustrine sedimentary rocks. Which neatly extends this out of the tectonic regime.

    So in response to your first point, the above suggests that it might not be all that simple to assess the causation of D-O events, in fact this science is not at all settled. In fact, if I had the time I could reference/quote many papers which suggest the recognition of D-O oscillations within both the Eemian and the Holocene. And they might be right. There do appear to be upper limits on earth’s warm state in the ride down from the PETM. So the D-O signal would be anticipated to be muted at the upper end of the scale and most observable in contrast to the cold state limits.

    The only ‘Tipping Point’ available is towards glaciation and the timing is anytime now. Even if we
    do not go into glaciation it is going to be cold not warm. In other words the Warmists are just blowing smoke and the IPCC has completely ignored what geology is saying on the subject.

    Another observation from ferdberple @ WUWT:

    Humans are optimized for heat. Our erect posture maximize evaporation and heat loss, while minimizing surface area exposed to the sun. This allows us to remain active for longer periods when it is hot as compared to other mammals. In contrast, survival times for naked humans in cold weather is measured in hours and minutes, while other mammals can survive indefinitely.

    While the average temperature of the earth is currently around 15C, for hundreds of millions of years the average was 22C. The same temperature we heat our houses in the absence of conservation. The same temperature that leaves on trees try and maintain to optimize photosynthesis….

    So that answers the question of what is the optimum temperature for life on earth, 22C not 15C. Graph of temperature over the last 65 million years.

  20. Gail Combs says:

    thefordprefect says on plant response to CO2…..
    C3 plants (99% of the plant species) were undergoing CO2 starvation when the earth is in the glaciation phase of the Milankovitch Cycle.

    Carbon starvation in glacial trees recovered from the La Brea tar pits, southern California

    The Royal Society: Carbon dioxide starvation, the development of C4 ecosystems, and mammalian evolution


    The CO2 concentration at 2 m above the crop was found to be fairly constant during the daylight hours on single days or from day-to-day throughout the growing season ranging from about 310 to 320 p.p.m. Nocturnal values were more variable and were between 10 and 200 p.p.m. higher than the daytime values. (wwwDOT)

    A wealth of information about CO2 concentration and nitrogen activity can be found here.

    Another reference BOOK

    In one peer reviewed article from 2005 it was found that in durum wheat the nitrogen level in the leaves decreased with higher CO2 but at the same time the nitrogen level in the stems and seeds increased. Both biomass and grain yields increased under all nutrient and water regimes where CO2 was higher. This agrees with UC Davis study. The authors measured the leaf nitrogen content and found it lower with increased CO2. However, UC Davis scientists failed (purposely?) to grow the plants to maturity and measure the nitrogen content in the seed. It appears that the plants in the higher CO2 regime are able to use less nitrogen to generate more leaf mass and then deposit the excess nitrogen in the seeds where it will be of benefit to the next generation.

    Atmospheric CO2 and Syrian Wheat Production

    Kaddour, A.A. and Fuller, M.P. 2004. The effect of elevated CO2 and drought on the vegetative growth and development of durum wheat (Triticum durum Desf.) cultivars. Cereal Research Communications 32: 225-232.
    What was done
    The authors grew three commercial cultivars of durum wheat (Triticum durum Desf.) registered in Syria (Cham 1, Cham 3 and Cham 5) from seed in 10-liter pots in different compartments of a phytotron, half of which compartments were maintained at an atmospheric CO2 concentration of approximately 400 ppm and half of which were maintained at a concentration of approximately 1000 ppm. Half of each of these treatments were further subdivided into two soil water treatments: well-watered, where available water content (AWC) was replenished to 90% of full capacity when it had dropped to 60%, and water-stressed, where AWC was replenished to 70% of full capacity when it had dropped to 45%.
    What was learned
    Averaged over the three cultivars, the extra 600 ppm of CO2 supplied to the CO2-enriched compartments led to total plant biomass increases of 62% in the well-watered treatment and 60% in the water-stressed treatment. Also of interest was the fact that the extra CO2 led to increases in the nitrogen concentrations of stems and ears. In the case of ears, nitrogen concentration was increased by 22% in the well-watered plants and by 16% in the water-stressed plants.

    What it means
    “These results,” according to Kaddour and Fuller, “have important implications for the production of durum wheat in the future.” They state, for example, that “yields can be expected to rise as atmospheric CO2 levels rise,” and that “this increase in yield can be expected under both water restricted and well irrigated conditions.” Hence, as they continue, “where water availability (irrigation) is a prime limiting economic resource, it can be distributed more effectively under higher CO2 conditions,” and “for countries such as Syria where average national production is well below the physiological maximum due largely to drought stress, the predicted rise in atmospheric CO2 could have a positive effect on production.” (wwwDOT)

    The UC Davis study of wheat and mustard going only so far as nitrogen content of the leaves is borderline fraud. This whole freaking AGW movement is replete with fraud because the IPCC mandate requires humans to be found at fault and that is where the grant money is at.