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My belief in Global Warming is getting shaky


engineerdude

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PS I saw a program on TV last week on outdoor experiments where they pump in extra CO2 to plants. I haven't found that TV program yet, but here is the outfit page that I think is running it. >> FACE Program, Brookhaven National Laboratory, BNL

 

Recently I was searching out plant growth and CO2 info and ran across some interesting studies. One study involved legumes CO2 and temps. What they found was some positive change with CO2 intro. When they boosted temps by some degrees in the enhanced CO2 environment, the growth of the plants was boosted greatly. Going from memory, 68 - 88% enhancement. I looked thru my bookmarks and cannot find the link, but maybe another could.

 

Another shorter study was via USDA regarding CO2 and corn. They found during the night hours, the CO2 level within (1 meter I think) of the corn jumped to around 700 ppm as the plant breathed oxygen and exhaled CO2 at night (a well known issue for home aquariums with plants and fish) then as the sun rose the reversal of this process brought the CO2 numbers back to normal ranges. They recognized more studies needed to be done using different plants to further understand the co2 +/- relationship.

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I would like to call to your attention the results of a UCSD study conducted in May of 2006. Specifically, this quote which speaks to the issue of plant intake of CO2:

 

 

UCSD Study Reveals How Plants Respond to Elevated Carbon Dioxide

 

One of the standard arguments against taking action to reduce emissions of carbon dioxide from the burning of fossil fuels is that the elevated carbon dioxide will stimulate plants to grow faster. The assumption is that plants will take up excess carbon dioxide to produce carbohydrates—their stored energy source.

 

However, studies have shown that, contrary to expectations, increased carbon dioxide does not accelerate plant growth. Previous research has also shown that the doubling of atmospheric carbon dioxide expected to occur this century can cause leaf stomata to close by 20 to 40 percent in diverse plant species, thus reducing carbon dioxide intake. Little was known about the molecular and genetic mechanisms controlling this response.

 

Schroeder and colleagues discovered that in the cells surrounding the leaf stomata calcium ion “spikes”—or rapid increases and then decreases in calcium ion concentrations within cells—changed in frequency according to atmospheric carbon dioxide levels. As the carbon dioxide concentration was increased, the rapid drum roll of calcium spikes within the cells changed to a slower beat. The cells responded by reducing the size of the pores in the leaf.

 

In the presence of low carbon dioxide, a quick drumbeat was induced, but the stomata opened, rather than closed.

 

 

You see, the increased concentration of CO2 in the atmosphere is actually causing the plants to intake less. This seems to inform the questions above as to why the plants don't seem to be keeping up / up keeping with all of the human inputs.

 

 

Turtle raised another valuable point in his post above, primarily when he mentioned deforestation, and how human development is causing fewer plants and more strip malls and housing subdivisions.

 

 

 

EDIT: Here's a link to the actual study I referenced above:

 

 

CO2 signaling in guard cells: Calcium sensitivity response modulation, a Ca2+-independent phase, and CO2 insensitivity of the gca2 mutant -- Young et al. 103 (19): 7506 -- Proceedings of the National Academy of Sciences

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I would like to call to your attention the results of a UCSD study conducted in May of 2006. Specifically, this quote which speaks to the issue of plant intake of CO2:

 

 

UCSD Study Reveals How Plants Respond to Elevated Carbon Dioxide

 

You see, the increased concentration of CO2 in the atmosphere is actually causing the plants to intake less. This seems to inform the questions above as to why the plants don't seem to be keeping up / up keeping with all of the human inputs.

 

EDIT: Here's a link to the actual study I referenced above:

 

 

CO2 signaling in guard cells: Calcium sensitivity response modulation, a Ca2+-independent phase, and CO2 insensitivity of the gca2 mutant -- Young et al. 103 (19): 7506 -- Proceedings of the National Academy of Sciences

 

I see that one study done on one type of plant "Arabidopsis; a genus in the family Brassicaceae. They are small flowering plants related to cabbage and mustard." Shows some inhibition of stomatal movements in response to CO2 dependent on the variety of Arabidopsis mutant.

 

What does stomatal apature movement do in regards to plant growth?

 

The study you linked to gives no indication on plant growth or productivity in heightened CO2 conditions.

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What does stomatal apature movement do in regards to plant growth?

 

The stomata are basically the "doorways" for stuff coming in and out of the plant leaf. If the stomata cinch up, then less respiration and photosynthesis occurs. The opposite occurs when the stomata open up. So, when the stomata are open, there's more potential for plant growth.

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The stomata are basically the "doorways" for stuff coming in and out of the plant leaf. If the stomata cinch up, then less respiration and photosynthesis occurs. The opposite occurs when the stomata open up. So, when the stomata are open, there's more potential for plant growth.

 

Not less growth (in an enhanced co2 environment), but maybe not extra growth for that particular type of plant.

 

I did not articulate my point well. The study linked to was not a 'big picture' study of plant growth in an enhanced environment and provided no information on whether higher Co2 impacted this particular type of plant positively or negatively. It was basically (for comparison) a study of how a frogs skin reacts in an enhanced/deprived water oxygen condition and how fast the skin reacts to the situation.

 

Common sense tells you that the frogs body is not going to kill itself off by taking in too much oxygen. We know plants turn their leaves towards the sun. The study linked to did not show plants intake less CO2.

 

A snippet from an easy to read site I found:

 

"There are tiny holes on the underside of plant leaves, called somata, which are the openings through which the plant absorbs CO2. With higher level of CO2 concentration in the air the somata do not have to be open as wide. The narrower opening means that less water is transpired and thus less water is required by the plants."

 

Is the above generally true with regards to stomata and its intake regulation of various plant needs?

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I have heard this before, and I find experiments contrary to Craig's indication.

 

CO2 Science

The link you provided, Turtle, does seem to tentatively support the idea of "natural sinks such as vegetation and the oceans will increase their rate of absorption to keep the amount at or near the present amount".
The linked-to article supports that plant growth, and correspondingly, carbon uptake, increase when [ce]CO2[/ce] concentration (dissolved in water) increase. However, looking in-depth at the first of the article’s referenced papers, Kubler, J.E., Johnston, A.M. and Raven, J.A. 1999. The effects of reduced and elevated CO2 and O2 on the seaweed Lomentaria articulata., the conclusion reached (illustrated most directly in figure 1) is not that carbon uptake rate is proportional to [ce]CO2[/ce] concentration, but that a “sweet spot” of maximum carbon uptake occurs at about double normal [ce]CO2[/ce] concentration ([math]7 \times 10^{-4}[/math]) and normal oxygen concentration ([math]9 \times 10^{-5}[/math]). At higher or lower [ce]CO2[/ce] concentration for the same oxygen concentration, the carbon uptake rate decreases. Oxygen concentration has little effect on carbon uptake up to about double normal [ce]CO2[/ce] concentration. When both [ce]CO2[/ce] and oxygen concentrations are higher than normal, greater than normal carbon uptake can also occur, but the authors found this unimportant, as they know of no mechanism by which this can naturally (including human influences) occur on a large scale.

 

It’s interesting to me that the co2science.org article appears to put a subtle “spin” – and some outright additions - on the paper’s data and findings – compare its “what was learned” section:

Oxygen concentrations ranging between 10 and 200% of ambient had no significant effects on daily net carbon gain or total wet biomass production rates in this seaweed. In contrast, CO2 concentrations ranging between 67 and 500% of ambient had highly significant effects these parameters. At twice the current ambient CO2 concentration, for example, daily net carbon gain and total wet biomass production rates were 52 and 314% greater than they were under ambient CO2 conditions. Even though this seaweed was likely carbon saturated, when grown at five-times the ambient CO2 concentration, it still exhibited daily net carbon gain and wet biomass production rates that were 23 and 50%, respectively, greater than those of control plants.

To the actual article’s abstract:

We grew a non-bicarbonate using red seaweed, Lomentaria articulata (Huds.) Lyngb., in media aerated with four O2 concentrations between 10 and 200% of current ambient [O2] and four CO2 concentrations between 67 and 500% of current ambient [CO2], in a factorial design, to determine the effects of gas composition on growth and physiology. The relative growth rate of L. articulata increased with increasing [CO2] up to 200% of current ambient [CO2] but was unaffected by [O2]. The relative growth enhancement, on a carbon basis, was 52% with a doubling of [CO2] but fell to 23% under 5× ambient [CO2]. Plants collected in winter responded more extremely to [CO2] than did plants collected in the summer, although the overall pattern was the same. Discrimination between stable carbon isotopes (Δ13C) increased with increasing [CO2] as would be expected for diffusive CO2 acquisition. Tissue C and N were inversely related to [CO2]. Growth in terms of biomass appeared to be limited by conversion of photosynthate to new biomass rather than simply by diffusion of CO2, suggesting that non-bicarbonate-using macroalgae, such as L. articulata, may not be directly analogous to C3 higher plants in terms of their responses to changing gas composition.

Based on the text on its homepage Co2science.org appears to promote 2 unconventional positions on greenhouse gasses and global warming:

  • that global warming is not occurring (“the fantasy world of Al Gore and James Hansen”)
  • that [ce]CO2[/ce] increases are occurring and will have a significant impact on global ecosystems, but are beneficial (“The Greening of Planet Earth … Is carbon dioxide a harmful air pollutant, or is it an amazingly effective aerial fertilizer?”).

This draws attention to, I think, the importance of tracing cited research back to its source, rather than trusting “repackaged” presentations of it by manifestly agenda-driven individuals and organizations.

I see no indication here of added nutrients. :read: :turtle:
What I was alluding to (rather ineptly, I fear :embarass:) is the idea of Iron fertilization, a proposed technique for increasing the rate of ocean carbon sequestration.

 

An interesting figure from this article is one known as the Redfield ratio, a formula relating the proportions of elements necessary for carbon uptake by phytoplankton: 380,000 C : 58,000 N : 3,600 P : 1 Fe. Although the iron (Fe) required is the most minor part of the formula, research indicates that for the majority of Earth’s potential phytoplankton, it is the “limiting reagent” in carbon uptake.

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The study linked to did not show plants intake less CO2.

Since you quoted my post originally, I can only presume you are referring to the study I shared. If that is truly the case, then your comment above does not seem accurate. However, if you can cite a few sources to support your position, sources which counter the claims made in the article I've shared, then I remain willing to ammend my position.

 

Until then, please see below.

 

 

PNAS Article cited above by InfiniteNow

 

 

From the abstract (emphasis mine):

Furthermore, low/high [CO2] transitions modulated the cytosolic Ca2+ transient pattern in Arabidopsis guard cells (Landsberg erecta). Inhibition of cytosolic Ca2+ transients, achieved by loading guard cells with the calcium chelator 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid and not adding external Ca2+, attenuated both high CO2-induced stomatal closing and low CO2-induced stomatal opening, and also revealed a Ca2+-independent phase of the CO2 response. Furthermore, the mutant, growth controlled by abscisic acid (gca2) shows impairment in [CO2] modulation of the cytosolic Ca2+ transient rate and strong impairment in high CO2-induced stomatal closing.

 

Stomatal pores in aerial parts of plants close in response to high carbon dioxide concentrations and open at low [CO2].

 

Reports show that a doubling of atmospheric [CO2] causes significant stomatal closure by 20–40% in diverse plant species.

 

 

 

From the Results section:

Thus in guard cells, the rate of [Ca2+]cyt transient production decreased after the switch from low CO2 buffer to high CO2 and increased after the switch back to low CO2 buffer (Fig. 1A), showing that the [Ca2+]cyt transient rate is modulated by CO2 concentration changes.

 

control experiments with 50 µM Ca2+ added to the bath solution, shifts from ambient [CO2] to low [CO2] caused stomatal opening and shifts from ambient [CO2] to high [CO2] caused stomatal closing.

 

 

 

 

However, if you were not responding the study I shared, then I apologize, and suggest the above be used simply as further evidence of the position I shared.

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Since you quoted my post originally, I can only presume you are referring to the study I shared. If that is truly the case, then your comment above does not seem accurate. However, if you can cite a few sources to support your position, sources which counter the claims made in the article I've shared, then I remain willing to ammend my position.

Until then, please see below.

PNAS Article cited above by InfiniteNow

From the abstract (emphasis mine):

From the Results section:

However, if you were not responding the study I shared, then I apologize, and suggest the above be used simply as further evidence of the position I shared.

 

Read the study again (not the press release).

 

No where does it make any claim about plant growth. The study does not say CO2 intake is reduced. It says stomata close at a higher rate (It does not say ALL STOMATA CLOSE). The study makes NO CLAIM regarding plant growth or amount of CO2 intake. It only claims stomata open or close in a different proportion than when CO2 levels are 'normal'.

 

No where in the study does it indicate plant growth is altered by the reaction of this type of plant to Higher or Lower CO2,

 

Post all the snippets you want from the study. None of them reflect plant growth or CO2 intake by this particular plant. Its no different than seeing someone squinting their eyes on a bright sunny day and concluding they must be blind.

 

What I am saying is that study provides no evidence either way on the effect on the growth of that particular type of plant in Higher or Lower CO2 environmental levels.

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No where does it make any claim about plant growth.

This would, in fact, be a strawman of my position, so your point is moot. My position referred only to the plants ability to absorb CO2, and how that ability is lessened as atmospheric CO2 increases.

 

 

The study does not say CO2 intake is reduced.

Are you suggesting that the closure of stomata has no impact on the plants ability to intake CO2? I am just trying to get you to clarify your position, as I'm sincerely unsure what that is.

 

 

It says stomata close at a higher rate (It does not say ALL STOMATA CLOSE).

This would be another strawman, as I never suggested that either. To put this out there, and make sure we're all clear on some of the things I DIDN'T say... I also didn't say that the plants were completely unable to absorb CO2 as atmospheric concentrations rise.

 

I'll stop there, as it's going to be quite impossible for me to remind you of all of the things which I DIDN'T say.

 

 

Post all the snippets you want from the study. None of them reflect plant growth or CO2 intake by this particular plant. Its no different than seeing someone squinting their eyes on a bright sunny day and concluding they must be blind.

 

What I am saying is that study provides no evidence either way on the effect on the growth of that particular type of plant in Higher or Lower CO2 environmental levels.

 

Please see my comment above regarding your complete misrepresentation of my position.

 

 

 

 

 

Is there a larger point you're trying to make here, or are you just content find some fallacy in INow's references?

 

If my previous experiences with Cedars are to serve as any indication, then it's more than likely the problem she has is with the person who shared the reference, and not the reference itself. If she were truly just a scientific hawk watching out for the welfare of accuracy and truth with no personal agenda, she'd have also come out and attacked Turtle for sharing his heavily biased data source and treating those quotes as valid and accurate representations... Which, she did not.

 

 

:)

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This would, in fact, be a strawman of my position, so your point is moot. My position referred only to the plants ability to absorb CO2, and how that ability is lessened as atmospheric CO2 increases.

 

Are you suggesting that the closure of stomata has no impact on the plants ability to intake CO2? I am just trying to get you to clarify your position, as I'm sincerely unsure what that is.

Its you who claims this and I only point out the study you refer to makes no such claim and this is your assumption.

 

I'll stop there, as it's going to be quite impossible for me to remind you of all of the things which I DIDN'T say.

 

Its good you stop there. Here is exactly what you said.

From the original post:

 

I would like to call to your attention the results of a UCSD study conducted in May of 2006. Specifically, this

quote which speaks to the issue of plant intake of CO2:

Cedars snips Press Release

 

You see, the increased concentration of CO2 in the atmosphere is actually causing the plants to intake less.

 

This is not claimed anywhere in the study.

 

This seems to inform the questions above as to why the plants don't seem to be keeping up / up keeping with all of the human inputs.

 

Again, nowhere in the study is this implied nor can one conclude the above to be true. This is not to say research into the answer to the question of whether plant CO2 intake is reduced in higher Co2 situations are not out there, but this study provides none of these conclusions.

 

Its not Cedars who introduced strawmen into this portion of the thread.

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Allegations of strawmen, personal animosity, plant stomata and Young et al.’s PNAS paper aside, the paper I linked to in post #40 shows clearly that common red seaweed actually decreases it rate of uptake of carbon when aqueous [ce]CO2[/ce] concentration exceeds about 2 times normal and [ce]O2[/ce] concentration is normal. It also shows that higher than normal carbon uptake occurs at greater [ce]CO2[/ce] concentrations when [ce]O2[/ce] concentration is also increased, but not to as great a rate as found at the “sweet spot” of about 2 times normal [ce]CO2[/ce] and normal [ce]O2[/ce].

 

Kubler et al don’t discuss possible biomechanical reasons for this, only their measurements and experimental technique, but a reasonable assumption that can be drawn from this and Young et al’s research is that, like animals and simpler chemical reactions, plants may metabolize more efficiently when subjected to unusual concentrations of [ce]CO2[/ce] and [ce]O2[/ce], but that the range of concentrations is limited. Plants being complex, highly evolved organisms, optimized to the conditions of their environments, this doesn’t surprise me.

 

I worry that this thread has focused so much on plant carbon uptake that we’re losing sight of the big picture of atmospheric carbon and carbon sequestration. As previous posts have noted, simply containing carbon in biomass doesn’t guarantee its long-term removal from the atmosphere – some mechanism must be present to physically isolate it from the atmosphere long-term. For example, terrestrial and shallow-water aquatic biomass can be compressed into sediments, and over a geological time scale, buried in deep fossil deposits that are (barring extraction and burning by a particularly ingenious species of ape) effectively eternal. Carbon in seawater can be absorbed by diatoms, then sink to the ocean floor to be sedimented into the ocean floor, subducted into the mantle, or frozen in methane ice. So simply increasing greenspace and/or plant metabolism doesn’t guarantee carbon sequestration.

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I worry that this thread has focused so much on plant carbon uptake that we’re losing sight of the big picture of atmospheric carbon and carbon sequestration. As previous posts have noted, simply containing carbon in biomass doesn’t guarantee its long-term removal from the atmosphere – some mechanism must be present to physically isolate it from the atmosphere long-term. For example, terrestrial and shallow-water aquatic biomass can be compressed into sediments, and over a geological time scale, buried in deep fossil deposits that are (barring extraction and burning by a particularly ingenious species of ape) effectively eternal. Carbon in seawater can be absorbed by diatoms, then sink to the ocean floor to be sedimented into the ocean floor, subducted into the mantle, or frozen in methane ice. So simply increasing greenspace and/or plant metabolism doesn’t guarantee carbon sequestration.

 

Exactly! :)

 

The decaying trees are part of the forest just as much as the live ones. Release and uptake, again and again.

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Allegations of strawmen, personal animosity, plant stomata and Young et al.’s PNAS paper aside, the paper I linked to in post #40 shows clearly that common red seaweed actually decreases it rate of uptake of carbon when aqueous [ce]CO2[/ce] concentration exceeds about 2 times normal and [ce]O2[/ce] concentration is normal. It also shows that higher than normal carbon uptake occurs at greater [ce]CO2[/ce] concentrations when [ce]O2[/ce] concentration is also increased, but not to as great a rate as found at the “sweet spot” of about 2 times normal [ce]CO2[/ce] and normal [ce]O2[/ce].

 

Kubler et al don’t discuss possible biomechanical reasons for this, only their measurements and experimental technique, but a reasonable assumption that can be drawn from this and Young et al’s research is that, like animals and simpler chemical reactions, plants may metabolize more efficiently when subjected to unusual concentrations of [ce]CO2[/ce] and [ce]O2[/ce], but that the range of concentrations is limited. Plants being complex, highly evolved organisms, optimized to the conditions of their environments, this doesn’t surprise me.

But you also have to keep in mind this particular type of seaweed is not known for using CO2 in its environment and the hypothesis was by increasing CO2 the plant would utilize this more (roughly translated). See the introduction for more.

 

Additionally, the plant growth itself was increased at all phases of increased CO2 with the best response being at a double from now CO2 level and even though this decreased with the 5x it was still 23% higher than what its growth rate is at 'normal' CO2 levels.

 

While the dry weight seems to show the plant doesnt store C13 in proportion to its growth rate, that only indicates more study should be done to see what the plant is doing with the carbon. One thing I didnt pick up on in the article was whether they increased other components used by the plant to grow or is the plant converting the extra CO2 into other energies to compensate for a different nutrient need. They list what they put in, but I do not know how that compares to their natural environment.

 

As someone who grows plants in an aquarium setting, adding CO to the water is a must for any medium and especially high light plants. Now for my low light plants? Those bad boys practically grow in the dark and you dont have to add CO2 to keep them growing well. As I understand this particular seaweed, its maybe a medium light plant, but its not a high light plant. I see they kept the ph pretty steady which indicates they kept the CO2 levels pretty stable.

 

Basic information for Lomentaria articulata (A red seaweed)

 

I remember reading some info on greenhouse tomatoes and they knew an average of how many mg or grams of CO2 an average tomato plant uses in a day, some even detailed for various parts of plant development.

 

So while there might be some plants which should not be considered for their carbon sequestering potential, this does not equal a higher CO2 environment negatively affecting their growth, nor does it indicate they stop consuming CO2 because more of its in their environment.

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I think it would be reasonable to say that different plants are going to react differently to increased levels of CO2 in the atmosphere. While I would agree that understanding this process is important, what appears to be more important, as Craig mentioned above, is the larger picture here.

 

What is clear is that the CO2 levels in the atmosphere are continuing to rapidly increase at a rate which natural CO2 sequestration processes apparently are not able to keep up with. Even though there are other natural contributing factors to CO2 and other greenhouse gases, it seems foolish to deny the strong correlation between the increase in the consumption of fossil fuels, the increase in atmospheric CO2, and the increase in the mean global temerature.

 

With this in mind, we should be making preparations to try and stabilize the conditions before they reach the dreaded "tipping point" at which it will be beyond our ability to control. These preparations should include, but not be limited to, the development of artificial CO2 sequestration methods, and the promotion of government policies that encourage, if not require, increased fuel economy standards, alternate sources of clean energy, recycling, and green development practices.

 

It simply makes sense to do these things anyway if we are to be good stewards of the only environment we have to live. The technology is available. Is it worth avoiding doing these things just so we don't have to be burdened with change, or so the fossil fuel industry doesn't have to sacrifice future profits? I don't think so, because if we don't change now, I believe we will be forced to change later, but the changes will be in the form of adaptation to a much more extreme environment.

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With this in mind, we should be making preparations to try and stabilize the conditions before they reach the dreaded "tipping point" at which it will be beyond our ability to control. These preparations should include, but not be limited to, the development of artificial CO2 sequestration methods, and the promotion of government policies that encourage, if not require, increased fuel economy standards, alternate sources of clean energy, recycling, and green development practices.

 

It simply makes sense to do these things anyway if we are to be good stewards of the only environment we have to live. The technology is available.

 

Stabilize?

 

The historic proportions of CO2 (as I understand it) indicate this current ppmv is an anomaly in the averages of the earth and quite low for what is the 'average' over the history of life on earth itself. I am unsure where this 'tipping point' exists.

Image:Phanerozoic Carbon Dioxide.png - Wikipedia, the free encyclopedia

 

Additionally, it appears the whole of human development occurred during one of these unusual cold snaps and to try to attempt to alter the big picture of what is normal for the earth based a limited perception of what we think is best seems quite impossible and likely a waste of resources. Climate change happens whether or not we are here to observe it personally.

 

Image:Phanerozoic Climate Change.png - Wikipedia, the free encyclopedia

 

Image:65 Myr Climate Change.png - Wikimedia Commons

 

http://upload.wikimedia.org/wikipedia/commons/6/60/Five_Myr_Climate_Change.png

 

If you really want to talk about 'tipping points' I would suggest that occurred around the time we hit 4 billion people (and rising).

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