Science tries to manipulate crops to grow better and give better yields. Monsanto is a great example for this in their genetically modified (manipulated) seeds. It seems that sciences collide when temperatures matter.
d/dx is giving general info without giving particular inferences to specific genetically modified crops (that's most of the crops being planted nowadays in Illinois). Living in the corn belt I do have plenty of large farming friends who always try and get the best yield from corn and soybeans, but seed companies seem to be complicating things with these GMOs.
Seeding fields can be awfully tricky, because the climates always change no matter where you live. Trying to get the most from a single planting is what a farmer tries to figure. Wheat isn't any different from corn or beans, They are trying to get the best "reap" they can with what they "choose" to sow.
Have you ever seen a list of the different types of corn, beans, or wheat?
BOTTOM LINE : CO2 matters to all of them. Higher CO2 (400ppm) intake makes them more resilient to many more perturbations than what they would at a lower rate (280ppm). More biomass actually creates more CO2 into the atmosphere from farming. Much more than what climate science "ALARMISM" is telling us.
From my link : " ... “Something is changing about this cycle; the ecosystems are becoming more productive, pulling in more atmospheric carbon during the summer and releasing more during the dormant period.”
“A simple picture is that plants breathe. You can see the seasonal impact of this in the Keeling curve, the famous graph that shows atmospheric CO2 levels measured from a mountaintop in Hawaii since the late 1950s,” explained co-author Eric Kort, an assistant professor at the University of Michigan. “While it’s been continually increasing, it wiggles up and down a bit each year, and that’s this seasonal breathing of the biosphere.”
Those wiggles have been growing larger over the past five decades, increasing by as much as 50 percent at half at higher northern latitudes, and scientists have not fully understood why. Much of the change is believed to be caused by the natural system reacting to an altered climate, with changes in photosynthesis, respiration and expansion of woody vegetation potentially involved. Again, though, the authors said that mankind was also likely involved. ... "
Since this question is in the GLOBAL WARMING section, I would like to note that the Keeling Curve is not a direct match with temperature increases. Crop production is very "in tune" with the Keeling Curve, which is a FACT that GLOBAL WARMING ALARMISTS always fail to realize. Most farmers know the "climate" better than climatologists do (IMO). They've been dealing with climate changes for most all of their lives. Most all of the farming families I know don't see "dramatic" changes in the climate and they have been farming for generations.
Another good reason for me to call 'environmental climate scientists' - "Climate Clowns"!
:-)
d/dx has a good answer which only relates to temperatures.
I suspect you are more interested in the effects of CO2, while some crops (sour orange) have shown not only increased fruit mass but also increased vitamin content, however with grains there may be a slight lowering of carbohydrate content, but this is hugely offset by the increase in overall yield.
More CO2 is better that is why many greenhouses now use CO2 supplementation.
Edit
Linlyons there is more greenery, as shown by satellites http://notalotofpeopleknowthat.wordpress... that is even taking deforestation into account, and more importantly it has increased more in arid, semi desert areas, making your subsistence farming crop yield decrease a lie.
First of all, correlation isn't not causation.
d/dx is right but he is missing a very important point. Canada is largely glacial soils which tends to be rich and Florida is pretty washed out by comparison. You don't have giant wheat farms in Florida.
Kano, as usual claims that more CO2 grows more food.
If that were true, then with the 40% increase in CO2, there should be far more greenery around the country.
And there is not.
Particularly in subsistence farming areas global warming has seen crop yield decrease.
d/dx does, as usual, have a good answer.
it is interesting how crops evolve to take advantage of their environment over decades.
d/dx has the answer and as usual kano assumes moisture remains the same. large areas will be more like deserts. california is a prime example. high temps and droughts kill crops regardless of co2 'plant food'
As far as I can recall, most grains have a *lower* yield, in terms of actual usable grain (rather than just plant biomass) in warm years/places. I know that, for example, Canada grows a lot more wheat (per unit area) than, say, Florida. If this is true, it suggests that global warming will tend to reduce rather than increase the yield of the crops that make up the base of most of our diets.
Does anyone either actually know of, or have reasonable or informed speculations about, *why* this occurs? Sources, as always, welcome, though at least if it's to a scientific paper, please try to add a layman-level explanation of your own.
