[Lemmy]

PluggyRug wrote:

I don't dispute anything you say, however atmospheric CO2 concentration would have to increase a hell of a lot to be harmful. Life flourished in the past with much higher levels. Also decreasing naturally occurring gasses can be dodgy.

"A hell of a lot" is a loose term. One guy says "I go to the movies all the time, usually once a month". Another guy says "I hardly ever go to the movies, only once a week or so". The truth is we just don't know the science yet. Given that uncertainty, prudence demands caution.

[bootlegga]

Lemmy wrote:

PluggyRug wrote:

In which way?

Depends which of the 3 things (CO2, O2 or sunlight) you're asking about and which type of lifeform.

For humans: CO2 - overdoses causes acidosis (among other conditions) which can be fatal; O2 - breathing highly concentrated oxygen causes lung damage. Ever heard of "anti-oxidants"? Oxygen exposure over a lifetime of breathing, destroys virtually all bodily systems. Oxygen is both necessary for life, in the short-term, and fatal for it over the long-term; sunlight - UV exposure causes skin damage and cancer, not to mention nasty, painful burns.

But I didn't really need to tell you any of that, did I?

Life on Earth depends on a delicate balance of conditions. Increasing the concentration/quantity of any naturally occurring gas in our atmosphere may have drastic effects on life on this planet. Take a SCUBA course and learn a little bit about how fucked up you can become by having your gas-blend even slightly off.

PluggyRug wrote:

I don't dispute anything you say, however atmospheric CO2 concentration would have to increase a hell of a lot to be harmful. Life flourished in the past with much higher levels. Also decreasing naturally occurring gasses can be dodgy.

Quote:

Earth's atmosphere today contains about 380 ppm CO2 (0.038%). Compared to former geologic times, our present atmosphere, like the Late Carboniferous atmosphere, is CO2- impoverished! In the last 600 million years of Earth's history only the Carboniferous Period and our present age, the Quaternary Period, have witnessed CO2 levels less than 400 ppm.

http://www.geocraft.com/WVFossils/Carbo ... imate.html

Did HUMAN life flourish at 600 PPM or just life? I don't know about you, but I'm not a dinosaur (no matter how much I wish it I were a T-REX ).

[N_Fiddledog]

I don't think I'd worry about acidosis.

Quote:

# Above 2%, carbon dioxide may cause a feeling of heaviness in the chest and/or more frequent and deeper respirations.

# If exposure continues at that level for several hours, minimal "acidosis" (an acid condition of the blood) may occur but more frequently is absent

http://www.inspectapedia.com/hazmat/CO2gashaz.htm

2% would be 20,000 ppm. 1% would be 10,000ppm Currently we're at 385 ppm.

Man is not capable of releasing enough CO2 into the atmosphere which might approach levels which could be considered in any way toxic.

Wikipedia uses this graphic. So for what that's worth...



The Jurassic period when dinosaurs were famous for running around went up to around 2,500 ppm.

[ShepherdsDog]

bootlegga wrote:

Lemmy wrote:

PluggyRug wrote:

In which way?

Depends which of the 3 things (CO2, O2 or sunlight) you're asking about and which type of lifeform.

For humans: CO2 - overdoses causes acidosis (among other conditions) which can be fatal; O2 - breathing highly concentrated oxygen causes lung damage. Ever heard of "anti-oxidants"? Oxygen exposure over a lifetime of breathing, destroys virtually all bodily systems. Oxygen is both necessary for life, in the short-term, and fatal for it over the long-term; sunlight - UV exposure causes skin damage and cancer, not to mention nasty, painful burns.

But I didn't really need to tell you any of that, did I?

Life on Earth depends on a delicate balance of conditions. Increasing the concentration/quantity of any naturally occurring gas in our atmosphere may have drastic effects on life on this planet. Take a SCUBA course and learn a little bit about how fucked up you can become by having your gas-blend even slightly off.

PluggyRug wrote:

I don't dispute anything you say, however atmospheric CO2 concentration would have to increase a hell of a lot to be harmful. Life flourished in the past with much higher levels. Also decreasing naturally occurring gasses can be dodgy.

Quote:

Earth's atmosphere today contains about 380 ppm CO2 (0.038%). Compared to former geologic times, our present atmosphere, like the Late Carboniferous atmosphere, is CO2- impoverished! In the last 600 million years of Earth's history only the Carboniferous Period and our present age, the Quaternary Period, have witnessed CO2 levels less than 400 ppm.

http://www.geocraft.com/WVFossils/Carbo ... imate.html

Did HUMAN life flourish at 600 PPM or just life? I don't know about you, but I'm not a dinosaur (no matter how much I wish it I were a T-REX ).

There were also extremely high levels of oxygen during the Cretaceous, which interfered with plant growth.

http://jxb.oxfordjournals.org/cgi/conte ... 52/357/801

[BartSimpson]

So far the consensus of the polling is 25 to 13 against the AGW party line.

[Lemmy]

BartSimpson wrote:

So far the consensus of the polling is 25 to 13 against the AGW party line.

That sounds about right: one third of the population possessing better than normal intelligence.

[BartSimpson]

Lemmy wrote:

BartSimpson wrote:

So far the consensus of the polling is 25 to 13 against the AGW party line.

That sounds about right: one third of the population possessing better than normal intelligence.

And, fortunately, another third are wise enough to listen to them debunk the BS coming from the people who think they are powerful enough to control the climate.

[N_Fiddledog]

Lemmy wrote:

BartSimpson wrote:

So far the consensus of the polling is 25 to 13 against the AGW party line.

That sounds about right: one third of the population possessing better than normal intelligence.

We keep hearing stuff like that, but just like with AGW crisis theory in general we're still waiting to see anything at all like it might be evidence.

[Lemmy]

N_Fiddledog wrote:

Lemmy wrote:

BartSimpson wrote:

So far the consensus of the polling is 25 to 13 against the AGW party line.

That sounds about right: one third of the population possessing better than normal intelligence.

We keep hearing stuff like that, but just like with AGW crisis theory in general we're still waiting to see anything at all like it might be evidence.

Which is why I selected #6 on the poll, even though I strongly suspect #1 is the correct answer.

[BartSimpson]

N_Fiddledog wrote:

We keep hearing stuff like that, but just like with AGW crisis theory in general we're still waiting to see anything at all like it might be evidence.

Oh, but they DO have evidence! See, once you exclude the 3,000 Russian weather stations that are showing no change or cooling since 1992 and once you "adjust" the data from the remaining weather stations to show the data you want them to show then you have perfect proof of global warming!

And we know that man is responsible for this because Algore, David Suzuki, and James Hansen said so. And, don't forget, we've also seen more proof from Hollywood about the dangers of global warming;



Actual adjusted image of New York City.

[PluggyRug]

Lemmy wrote:

PluggyRug wrote:

I don't dispute anything you say, however atmospheric CO2 concentration would have to increase a hell of a lot to be harmful. Life flourished in the past with much higher levels. Also decreasing naturally occurring gasses can be dodgy.

"A hell of a lot" is a loose term. One guy says "I go to the movies all the time, usually once a month". Another guy says "I hardly ever go to the movies, only once a week or so". The truth is we just don't know the science yet. Given that uncertainty, prudence demands caution.

Loose term maybe, but then again, I never go to the movies.....if you looked at the link, it is a hell of a lot.

"we don't know the science" then what where all those "delegates" doing at Copenhagen. Maybe the word 'dollar' comes to mind.

[Zipperfish]

N_Fiddledog wrote:

Don't Oceans release a varying amount around 330 GT annually, and isn't there a natural bio release of about 220 GT?

I'm sure the oceans release lots, and reabsorb lots as well. But the idea of a "forcing" is that the CO2 being introduced through carbon combustion is carbon that has been out of the carbon cycle for a few million years.

The idea is that there is a dynamic equilibrium, and that forcing that equilbrium through the injection of new CO2 could change the equilibrium.

Quote:

That's kind of deceptive isn't it? I mean, wouldn't you have to compute in stuff like Henry's law, land use changes, and the natural carbon cycle?

Not intentionally. I'm just trying to demonstrate that the amount of CO2 we generate from fossil fuel combustion is an appreciable portion of the entire carbon cycle.

Quote:

I'm not saying anthropogenic doesn't make a dint. But I've been trying to figure out how sure we are how much comes from where, how exactly it's cycled, and I'm not sure we really know.

I don't think so either. To me, that's the main area of uncertainty. I guess we're pretty sure that we're in a warm spell, and we're pretty sure that CO2 has been going up. But then we move into the proxy measurements, and teh uncewrtainty goes up an order of magnitude and then the uncertainty becomes greater than the effect you're trying to discern. To me, that's the big issue facing climate science.

[N_Fiddledog]

Zipperfish wrote:

N_Fiddledog wrote:

Don't Oceans release a varying amount around 330 GT annually, and isn't there a natural bio release of about 220 GT?

I'm sure the oceans release lots, and reabsorb lots as well. But the idea of a "forcing" is that the CO2 being introduced through carbon combustion is carbon that has been out of the carbon cycle for a few million years.

The idea is that there is a dynamic equilibrium, and that forcing that equilbrium through the injection of new CO2 could change the equilibrium.

I'm not sure I get you. Natural forces have set climate both warmer, and much colder than we'd like it. Is that equilibrium? Radical changes have happened in climate through natural forcings we don't understand. Sometimes (the PETM for example) it's more like chaos, than equilibrium.

Let's pretend we actually could willfully force a significant change on climate though. Say we could stop the next inevitable ice age. Wouldn't that be more like equilibrium?

[Zipperfish]

N_Fiddledog wrote:

I'm not sure I get you. Natural forces have set climate both warmer, and much colder than we'd like it. Is that equilibrium? Radical changes have happened in climate through natural forcings we don't understand. Sometimes (the PETM for example) it's more like chaos, than equilibrium.

Let's pretend we actually could willfully force a significant change on climate though. Say we could stop the next inevitable ice age. Wouldn't that be more like equilibrium?

I think that in the terms I was using it, the equilibrium refers to resistance to change. In Figure A, the ball can be moved left or right a little ways (techncailly referred to as a "forcing," since force is required to push the ball uphill) and it will roll back down to its equilibrium (lowest energy) state. Negative feedbacks act against change and return the system to its equilibrium (low energy) state. Positive feedbacks amplify the change.



The most common mathematical models used to represent these are predtaor-prey population models (a prey increases in size until in gets too plentiful, at which time it causes a population explosion in the predator, who then eat all the prey and then the predators suffer a population reduction, leading to more prey). There's a stable but dynamic solution (in theory) to how predator-prey populations change over time.

Figure B is also in equilibrium, though this is an unstable equilibrium since one nudge (forcing) in either diorection and it falls.

Figure E is how I see the climate. If you force the ball far enough from its equilibrium state it reaches a tipping point (apoint of unstable equilibrium). If the forcing continues the ball could fall to a new low level equilibrium state that could be completely different from the old one. Figure E is metastable equilibrium.

http://classes.entom.wsu.edu/529/Stability.htm

So-called "natural" forcings can and do act to change the equilibriums over time. The concern with climate change is that the "anthrpogenic" forcing will shift the system to a tipping point and/or that the anthrpogenic forcing is so fast (on geological time scales) that more powerful but slower negative feedback systems won't react in time.

There's also the issue of the time-scale of the various feedbacks involved--at which point do they happen and how fast do they act. And rather than explain that, I just found a Lindzen paper that discusses this:

http://wattsupwiththat.com/2009/03/30/lindzen-on-negative-climate-feedback/

[N_Fiddledog]

For me it comes down to this...

Zipperfish wrote:

So-called "natural" forcings can and do act to change the equilibriums over time. The concern with climate change is that the "anthrpogenic" forcing will shift the system to a tipping point and/or that the anthrpogenic forcing is so fast (on geological time scales) that more powerful but slower negative feedback systems won't react in time.

There's also the issue of the time-scale of the various feedbacks involved--at which point do they happen and how fast do they act. And rather than explain that, I just found a Lindzen paper that discusses this:

http://wattsupwiththat.com/2009/03/30/lindzen-on-negative-climate-feedback/

I don't really have much of a problem with that, except maybe...

Quote:

The concern with climate change is that the "anthrpogenic" forcing will shift the system to a tipping point and/or that the anthrpogenic forcing is so fast (on geological time scales) that more powerful but slower negative feedback systems won't react in time.

I've yet to see any evidence of, or need to worry about an anthropogenic forced "tipping point". In fact, you link to the Lindzen posting at Watts. Remember this bit?

Quote:

The Bottom Line

The earth’s climate (in contrast to the climate in current climate GCMs) is dominated by a strong net negative feedback. Climate sensitivity is on the order of 0.3°C, and such warming as may arise from increasing greenhouse gases will be indistinguishable from the fluctuations in climate that occur naturally from processes internal to the climate system itself.

I'd also like to see some evidence of anthropogenic forcing beyond anything we've seen in the natural world.

Ever seen this 4 part lecture series from Bob Carter?



It goes into what the geological data tells us. He's a geologist. Now people like Michael Mann might disagree with his facts, but Carter is a learned guy in his field, and he's worth listening to. It's worth seeing the other side. Carter says nothing is happening as far as speed and force of change, we haven't seen before.