The causative factor requires a functioning model. There are too many variables to claim causation without a model.
My biochemistry is a completely different subject which gases build up heat when hit with the sun.
Again, it has been shown that even on Venus where the CO2 dramatically higher... the issue is not the CO2 at all but rather the density of the atmosphere itself. You could put that much oxygen on Venus and it be about the same temperature it is now.
The entire concept of greenhouse gases as relevant to global atmospheres is likely vastly over stated.
Venus is the extreme case. All the failed though still supported climate models for the earth were adapted from models of Venus. And they're wrong because they assume the chemistry of the atmosphere matters.
Do this... find the air pressure of Venus at the "surface". Note that temperature. Now compare that to Jupiter at the same air pressure. You'll go about a third into Jupiter's atmosphere I think. The temperature is somewhat similar. Its not exact but it is in the ball park.
Do the same thing with the earth only in reverse. Get the air pressure of earth... 1 atmosphere obviously. And then go to Venus and see what the temperature of that atmosphere is at 1 atmosphere. You'll find it to be within the range of earth's atmosphere.
Which means pressure is far more relevant then gas composition. After all, Jupiter, Venus, and Earth have completely different atmospheric chemistries.
That I've done these calculations and you have not should give you pause. I have actually looked at this issue. I know about the Japanese earth simulator and you didn't know. Consider just for the sake of argument that I could be in command of more facts.
As to nitrogen and oxygen not having a big impact on the global atmosphere, that is impossible. If I removed those gases from the atmosphere, the atmosphere would be a great deal thinner. And it would therefore be a great deal colder. Forget what impact this would have on life. If we just concern ourselves with the temperature consequences, removing that nitrogen and oxygen from the atmosphere would radically reduce the temperature of earth. We'd be looking at a Martian climate.
As to heat reducing crop yields, you're not controlling for water in those statistics so it could all be water.
Look, I have a green house. I have thousands of plants.
Do you know which plants don't like being 95 degrees? Basically none of them. What kills them all is getting too much water and some of them have problems if it goes over 100. But up to 95 degrees they're all really happy. What is more that is very species specific. Certain species like it colder and some like it even hotter. You can take some species up to 120 and they're perfectly happy with it. I don't go that hot because I don't grow that many species like that and I find the temperature personally unpleasant so I don't let the green house get that hot.
Point is, if you want to have a scientific discussion then you're going to have to use good data. Using statistics from the USDA are not relevant to this discussion because they're not properly controlled for any one variable. They're really just yield statistics. It is like trying to use US Census statistics to judge the psychology of the nation. You can't do that. The data isn't taken in such a matter that it is clean enough to do that. Mostly what the census and yield stats give you is how many people we have and how much corn we have respectively. They can't really tell you what a long term climate change would have on global agriculture.
For one thing, they grow wheat in Canada. Think about that. They do that NOW. Now global warming will have the biggest impact on polar and sub polar climate zones and the least impact on the equatorial climate zones. The temperature rise under global warming is a global NORMALIZATION of climate. That means, that as the planet goes through AGW northern climates will become less harsh. That is the primary effect off this theory. Which means places like Canada and Russia could well turn into bread baskets. The population of these places could sky rocket either through population migration or simple breeding. And the ability of these zones to produce food will skyrocket at well.
I'm not sure you're aware of how your own theories work. They don't make everywhere 2 degrees warmer. They make some places 10 or 20 degrees warmer and some areas 5 or 10 degrees warmer. And over all you get a 2 degree warming if you average it out. But at the equator for example there shouldn't be any warming.
As to water, there is enormous amounts of water in the north west, north into canada, and of course huge amounts in the east.
As I said, this is an undertaking that could cost over 1 trillion dollars but that is less then our last war and really it could cause the middle of the country to bloom. So why not.
As to the drought conditions California is experiencing, that was what this whole thread was supposed to be about. And the scientists concluded it was a normal predicted climate pattern.
Last time this happened in the 1970s, California made plans to expand their water infrastructure mostly in storage so they could better weather a 2 to 4 year drought. They didn't build any of it and here we are with the same problem all over again. Had they built it, they wouldn't be in any trouble. Everyone with a clue knows this.
The Australians in Sydney have the same situation. They had a big bad drought decades back, planners said "dam these rivers, build up this many acre feet of water, etc"... and they didn't do it because they thought the river was pretty. Well... then they're in a serious drought condition later. Surprise surprise.
As a counter solution, are you aware of the Tasmanian aqueduct plan? Tasmania has an abundance of fresh clean water. It has literal rivers that flow into the sea all the time because they will never be able to use it all. The concept is to run a pipe from a large lake in Tasmania, under the sea like a garden hose, and then have it spit that water out on the mainland of Australia. The expense would be about a billion which is less then what Sydney is spending on a desalinization plant. The output would also be a great deal higher.
Aqueducts. We have lots of water. It is just in the wrong places. The Romans once wanted to build a city on a hill top. The problem was that there was no water up there. So they looked around and found another hill top some 40 miles away that had lots of water just bubbling out of the ground. The Romans built a pipe from that hill top to the next. The water flowed down the pipe, built up pressure, went up the next hill and into their city with no added power. Just gravity to move water from one hill, across a valley, and into their new town.
That was at least 1800 years ago. We move water hundreds of miles. But there is no reason why we can't move water thousands of miles. All we have to do is keep the input higher then the output... and the water will flow.
As to CO2 and ice ages, what you really did was disqualify the subject entirely. And that's fine. If I can't cite it then you're not going to do it either. You can either accept that the CO2 was higher during some the old ice ages or I don't want to hear about CO2 and ice ages from you.