There Was Once a Lot More CO2 In The air

[Jccarlton]

Plants loved it:

http://alfin2100.blogspot.com/2010/02/p ... -more.html

And the planet did not burn.

[KitemanSA]

Plants loved it:
And the planet did not burn.

The sun was dimmer back then.
I am beginning to think that we, the "human race", were created by Gaia to put CO2 BACK into the atmosphere so the plants might once again thrive, but to shield the planet from the ever increasing rays of the sun. The second part takes technology.
Mega-engineering to change the albedo of the Earth... THAT is what is needed!
Save Gaia, burn carbon!

[Betruger]

Or put CO2 in the atmosphere to prolong an interglacial.

[seedload]

"Most plants and corals evolved in an atmosphere with much higher concentrations of CO2 than currently exist around the planet (click on graph at right)."

Assumes that the plants then stopped evolving as CO2 levels went down. Seems to imply that they are now starved for CO2 because of this halted evolution. Not buying it.

"In fact, most plants and sea creatures crave more CO2 for optimal growth, and would grow faster and larger if provided with more CO2 food."

It has what plants crave.

Using a word like crave is disingenuous and pretty unscientific if you ask me. I certainly hope that plants (in the real world) will continue to demonstrate that they will grow faster and suck up some more CO2, but they are clearly not keeping up. So, if warming due to CO2 is a problem, don't count on the plants to save us.

I don't think warming due to CO2 is a problem. But, giving an AGW supporter a bit of credit, I wouldn't say that their argument is not about plant growth but rather that it is about temperature and sea levels.

[pfrit]

Actually, the sun has been hotter and colder throughout history. It is a variable star. I believe it is colder now as compared to earlier. Remember that the Earth is way out of the Sun's biosphere now. Without greenhouse effects, it would be an ice ball.

They have done experiments with higher CO2 levels on plants. As I recall, poison ivy in particular loves it, but all plants do better.

[Heath_h49008]

That's why Brawndo is Carbonated!!!



It's got what plants crave!!!!

[Maui]

Nobody's claiming the Earth is going to burn. Nobody's claiming that life won't thrive. Okay maybe that's the impression "alarmists" leave (and that is unfortunate), but I think it is also the fault of skeptics building strawmen by intentionally exaggerating the words of "alarmists".

Life certainly will thrive under high CO2, but that doesn't mean that the transition won't cause a lot of costly problems in the process.

[KitemanSA]

Actually, the sun has been hotter and colder throughout history. It is a variable star.

I am not talking about the minor ups and downs of the "variable star" nature of the Sun, but:

The Sun used to be fainter in the past, which is possibly the reason life on Earth has only existed for about 1 billion years on land. The increase in solar temperatures is such that already in about a billion years, the surface of the Earth will become too hot for liquid water to exist, ending all terrestrial life

We are only half way from "too cold" to "too hot" but we have already run out of CO2.

Save Gaia, burn carbon!

[Heath_h49008]

If the data was in any way correct, AGW wouldn't be a scandal, and Jones and others wouldn't be fearing criminal prosecution.

Can we thicken the atmosphere? Yep! Not very much..

But, if the sun heated the planet to the point the methane "snow" that rests on the ocean floor turned into a gas and entered the picture... we might have a real "Greenhouse" on our hands.

But the high CO2 level would cause increased plant and animal growth, and lock all your lovely gas right back up under water and in solid forms.

The system will find equilibrium based upon the amount of energy coming in from the sun.

[KitemanSA]

The system will find equilibrium based upon the amount of energy coming in from the sun.

Until you run out of one of the means that is used to maintain said balance. If Gaia has been losing CO2 to balance the Sun's input, she may be in trouble! No more CO2 to lose! It may be our job to find a DIFFERENT way to balance the system and put the CO2 back.

Hmmm. Just a thought.

[MSimon]

Assumes that the plants then stopped evolving as CO2 levels went down. Seems to imply that they are now starved for CO2 because of this halted evolution. Not buying it.

It is actually documented. Which is why some greenhouses enhance the CO2 in their atmosphere to improve plant growth.

[CaptainBeowulf]

Well a lot of plant species that exist today are smaller versions of ones that existed in the time of the dinosaurs. Crank up CO2, and you'll get giant ferns and giant sumak again.

My personal hope is that humanity evolved in order to move the earth away from the sun when it gets too warm. And when it goes supernova? Move it to another star system. With another billion years we should have figured out graviton/inertial drives by then, plus force fields to hold in the atmosphere, and some sort of heating system to keep the planet warm in interstellar space.

Of course most of us may live on the interior surface of Dyson Spheres or Ringworlds by then, but I think the old home planet should be kept around for sentimental value.

[MirariNefas]

Assumes that the plants then stopped evolving as CO2 levels went down. Seems to imply that they are now starved for CO2 because of this halted evolution. Not buying it.

It is actually documented. Which is why some greenhouses enhance the CO2 in their atmosphere to improve plant growth.

Wow, they documented that evolution has stopped, eh? Man. You should call the creationists, they'd love this.

Of course, please note that in greenhouses, we provide fertilizer. Full of nutrients, the other limiting reagents in plant growth. In the field, more CO2 does mean more growth, but there are limits, particularly nitrates and phosphates. Can they maintain a different overall stoichiometric balance? A little. They already shift that around a bit. But they aren't optimized for a massively different balance, so you'll have diminishing returns, and eventually toxicity (toxicity is probably pretty far off though).

[MSimon]

Assumes that the plants then stopped evolving as CO2 levels went down. Seems to imply that they are now starved for CO2 because of this halted evolution. Not buying it.

It is actually documented. Which is why some greenhouses enhance the CO2 in their atmosphere to improve plant growth.

Wow, they documented that evolution has stopped, eh? Man. You should call the creationists, they'd love this.

Of course, please note that in greenhouses, we provide fertilizer. Full of nutrients, the other limiting reagents in plant growth. In the field, more CO2 does mean more growth, but there are limits, particularly nitrates and phosphates. Can they maintain a different overall stoichiometric balance? A little. They already shift that around a bit. But they aren't optimized for a massively different balance, so you'll have diminishing returns, and eventually toxicity (toxicity is probably pretty far off though).

I guess I should have made my emphasis clear. I was not commenting on evolution. I was commenting on starved for CO2. AFAIK the effect of CO2 is linear up to about 1,000 ppm or so.

[taniwha]

seedload commenting that plants stopped evolving was rather disingenuous (and yes, I checked the meaning of that word). The original text made no such implication.

Plants have been evolving for the lower CO2 levels... by getting smaller.