What will we do for Carbon , for life and plant growth?

[AlbertaFarmer5]

i still wanna see your solar panels ?
went by yesterday , are they hidden , behind the bush maybe ? , guess i shoulda came in ?

Funny how he never responds to any of your posts on this topic...

[AlbertaFarmer5]

So what is the yield difference between 300 ppm and 400 ppm CO2? Assuming everything else is the same.

While there is overwhelming data and studies about raising CO2, and the benefits to yield, water use efficiency, disease tolerance, shortening the growing season etc, data on lower CO2 levels is not nearly as in vogue, for obvious reasons. But here is an interesting source regarding greenhouses, where the CO2 level naturally falls to the 200 ppm range without supplementation:
http://www.omafra.gov.on.ca/english/crops/facts/00-077.htm http://www.omafra.gov.on.ca/english/crops/facts/00-077.htm

All plants grow well at this level but as CO2 levels are raised by 1,000 ppm photosynthesis increases proportionately resulting in more sugars and carbohydrates available for plant growth. Any actively growing crop in a tightly clad greenhouse with little or no ventilation can readily reduce the CO2 level during the day to as low as 200 ppm. The decrease in photosynthesis when CO2 level drops from 340 ppm to 200 ppm is similar to the increase when the CO2 levels are raised from 340 to about 1,300 ppm (Figure 1). As a rule of thumb, a drop in carbon dioxide levels below ambient has a stronger effect than supplementation above ambient.

So, just like CO2's benefit as a greenhouse gas is logarithmic, not linear, so are its benefits for photosynethis. As noted above, dropping the level from 340 to 200 causes as much loss of photosynthesis, as going up by almost 1000 ppm. Same with temperature, at very low levels of CO2, additional CO2 has significant benefits as a greenhouse gas, raising CO2 above 300 ppm has almost no additional warming benefits, and gets progressively less at higher concentrations.

Here are links to a bunch of papers on CO2 and wheat yields, I don't think any of them discuss lower CO2, only the large yield increases ( especially under water stress) under elevated levels of CO2, might be a reasonable starting point to apply the same logarithmic relationship in the above paper, to the yield benefits here and get a good first approximation at lower levels:

http://www.co2science.org/subject/a/summaries/agriculturewheat.php http://www.co2science.org/subject/a/summaries/agriculturewheat.php

Unlike Chuck's unknown quantity of the amount of time it will take for anthropogenic elevated levels of CO2 to decline, this is real quantifiable evidence based science. The benefits are tangible and provable, Chuck's crackpot doomsday scenarios are not.

Hey A5 go ahead and show us your model that takes into account the residence time of CO2 and proves all the climate scientists are wrong! You have lots of time.

Give us the numbers and a graph or 2 would be nice!

We are waiting.......

i still wanna see your solar panels ?
went by yesterday , are they hidden , behind the bush maybe ? , guess i shoulda came in ?

[tweety]

Plants grew just fine at 280 ppm, because the plants only goal is to reproduce, they are not concerned with feeding xbilllions of people and their livestock, and their cars and powerplants and sawmills, and pulp mills etc.

Humans on the other hand, have very different goals for plants.

Estimates of pre industrial/pre colonial agriculture are somewhere between 2 and 4 hectares per capita, we are currently at 0.18 hectares per capita, it was nearly 3 times that as recently as 1950. We have very high expectations of our plants now, compared to 200 years ago, when famines, malnutrition and mass starvation were just facts of life. Obviously, there are many other factors that have led to these drastic increases in yield, primarily fertilizers, also mechanisation, genetics, chemical pest control, collective knowledge, improving weather, global warming, etc. But increased atmospheric CO2 is well documented as an important factor, even more so in arid, drought prone areas.

200 years ago, farmers (and plants) only had just over a billion people to feed with a very meagre diet, and very often, they failed at even feeding that number.

If you want to go back further to the depth of the past ice ages, CO2 dropped as low as 180 ppm, just ~30 ppm above the level necessary for life. While not a concern on human life timescales, it is humbling to think about.

Everyone has seen the drawing of the barrel with the differnt lengths of staves representing the limiting factors for crop growth. CO2 is most definitely one of the biggest staves, along with water and sunshine, the rest are minor in comparison.

So what is the yield difference between 300 ppm and 400 ppm CO2? Assuming everything else is the same.

Hey A5 go ahead and show us your model that takes into account the residence time of CO2 and proves all the climate scientists are wrong! You have lots of time.

Give us the numbers and a graph or 2 would be nice!

We are waiting.......

Whats this “we” shit ?

[shtferbrains]

So Chuck, if carbon tax and climate change mitigation are the solution to things like the wildfires in California, how long till we see that problem solved?

Next year if we try hard, ten years, 100 years, or maybe 100,000yrs like your chart shows ???

Pick the one you think is most probable relate your answer to your chart from post 33

[sumdumguy]

People who have no scientific background are so easily duped. And that’s 90% of the mass insanity.
Incredulous, preposterous suppositions are the foundation for destroying a somewhat vibrant economy.

[AlbertaFarmer5]

Hey A5 go ahead and show us your model that takes into account the residence time of CO2 and proves all the climate scientists are wrong! You have lots of time.

Give us the numbers and a graph or 2 would be nice!

We are waiting.......

I would if I had a numerical value for residence time and Charney sensitivity. Is it impossible to create a model which would have any predictive value when two of the most important variables are apparently completely unknown.
Since this is your crusade, and you are the advocate for ensuring all claims are backed by scientific evidence, I assumed you would have made sure you knew all the details before coming on to a public forum and throwing accusations around. You know, just incase someone calls you out on it.

[chuckChuck]

Hey A5 go ahead and show us your model that takes into account the residence time of CO2 and proves all the climate scientists are wrong! You have lots of time.

Give us the numbers and a graph or 2 would be nice!

We are waiting.......

[AlbertaFarmer5]

Good job there A5 keep discussing and bringing up a relatively insignificant issue that no climate scientist is concerned about! LOL.
You are Obsessive and grasping at straws, thinking the residence time of CO2 is going to change The outcome of millions of years of stored CO2 From fossil fuels going into the atmosphere in a few hundred years.

But keep denying that human caused climate change is an issue even when every major scientific organization in the world disagrees!

If they aren't concerned about residence time, then how do they come uyp with their alarmist models, which have different pathways based on different levels of CO2 emissions going forward. Wouldn't they need to know that input to make a model based on lower emissions?

Wouldn't they also need to have an exact number for the Charney sensitivity?

Have you done any projections, say financial, and and tried using an infinite range for one of the main input values? Can you guess what the output is going to be? Can you add GIGO to your list of acronyms?

Oh, and congratulations, up to 5 pages already, looks like you might yet exceed the 8 pages it took for you to reveal the math behind the natural sea level rise in that thread.