The headline is clearly wrong. Maybe they should have said "current trees". The tree tech has already been invented to circumnavigate present restrictions in tree biological restrictions. Very clickbait-y.
Sounds like it's a bit more nuanced than the headline would suggest. More CO₂ only means more growth when CO₂ is the limiting factor on growth in the first place. Water, nutrients, and sunlight all play a role as well.
Bingo. While not usually the limiting factor in nature, it can still be a benefit when it is. Just ask all the 1000s of pot growers literally burning propane to produce it indoors and vent it to atmosphere. Grr.
if its done properly excess O2 water vapour heat,and ethane and methane is vented, CO2 is assimilated and effluent atmosphere will have less than atmospheric amounts of CO2.
I’ve heard this argument before from climate change deniers. From a laypersons point of view I wonder why would you assume more CO2 makes trees grow more? More oxygen doesn’t make humans grow more, in fact it becomes toxic.
then again the original comment is also in either bad faith or ignorance since he's comparing humans to plants when they have completely different metabolic systems.
By mass, trees contain more oxygen than carbon. So do humans. Water is 89% oxygen by mass. Cellulose is 49% oxygen by mass. Dry wood contains a bit more carbon than oxygen, but living trees do not.
It's also so trivially easy to refute. If CO2 was a significant stimulant for plant growth, they'd be sucking it out of the air as fast as we were putting it out, and the whole issue would be moot.
I'm not sure that's a good argument. It's entirely plausible that plants need CO2 to exist at a particular partial pressure to absorb it. In the same way people wouldn't drag the O2 level in a sealed room down to 0%.
Humans can't bring the level near 0% because they would die long before that. Humans need between 19% and 24% O2. Below 19%, humans can't exert much energy without passing out. Above 24% increases damage from free radicals.
Putting a lot of shit around the foot of a plant can make it grow faster and better. Not so much humans. I understand your point but your argument is terrible.
We "assume" that because we can demonstrate it to happen. Place a tree in an enclosure, increase the CO2 level but otherwise keep things the same as outside the enclosure. Trees within the enclosure grows faster than the ones outside the enclosure.
This is not surprising, as we already know trees and plants consume CO2 to produce cellulose and other plant materials.
This is heavily exploited in greenhouses which are CO2 enrichened to produce better yields - albeit used mostly for growing vegetables, not trees.
Greenhouses are controlled environments where everything else is abundant too. In more natural environments, plants are limited by availability of water and nutrients in the soil.
On top of that, plant growth can be reduced by heat stress. They also have to contend with insects and disease, and may not have good defenses when climate change has brought invasive organisms to the area.
Sure, but what that suggests is that the existing established understanding is correct (or at least still plausible): even if the particular trees studied here aren't CO2-limited and don't grow more with more CO2, total plant biomass will or at least might (outside of climate change denial fantasies this doesn't mean increases in CO2 will automatically be neutralized by plant growth, because it doesn't imply that the size of the effect is necessarily sufficient to clear the additional CO2 once long-term equilibrium is reached, doesn't tell you how long it takes plants to reach the new equilibrium when CO2 levels have reached a new plateau, and even if it did all that wouldn't help when CO2 levels are constantly increasing and plant growth can't catch up.)
Sure, if everything else is ideal then many plants will grow more with more CO2. Even this study's authors don't deny that; they say that other factors will often not be ideal:
"climate change is generating warmer, drier conditions that could make them grow less in many places"
Overall, conditions are definitely getting warmer on average, and many places are also getting drier, sometimes with occasional very heavy rainfalls that wash away topsoil.
Another factor I didn't mention is forest fires, brought about by drier conditions, as we've been seeing in California.
I'm not taking issue with the study or it's authors, just the presentation of the article, which very heavily spins it, especially up front, as contradicting the existing understanding broadly, when it really doesn't.
It's important, because the fertilizer for anti-science attitudes exploited by groups like climate denialists is a false impression of radical flip-flops in science conveyed by popular media which uses exaggerated contradiction to overplay the impact of stories and draw eyeballs.
Based no my limited knowledge in this field, I believe that is because it is an enclosed and controlled system. You can increase all variables (CO2, water, nutrients) together; whereas, a plant in "the wild" cannot. Most things act more conservatively in Nature versus human controlled environments.
A number of problems with this method of study, and the headline is misleading.
The real question is whether there will be more biomass and more photosynthesis in response to more CO2, not whether individual trees grow more. The climate skeptics don't say tree trunks will get wider, they say there will be more plant biomass.
And also this is adding in confounding variables and saying more CO2 could change precipitation in certain places, and thus cause lower growth. Other studies that show more growth with more CO2 are using greenhouses to control for confounding variables.
And even if you are trying to answer the question in terms of a holistic analysis, you can't just study one forest in Canada and then make any kind of conclusion.
You'd need to study trees from most of the major forests, and look at the density of the foliage in each.
> The climate skeptics don't say tree trunks will get wider, they say there will be more plant biomass.
Speculating that plant biomass might help mitigate global warming doesn't really deserve the label "climate skeptic." It's already confirmed that rising CO2 affects crop growth rates.
What do you mean by mitigate global warming? I think what they argue is that there will be winners and losers, and it isn't some kind of black and white issue.
For instance, the Saharan desert seems to be greening.
The study is about sub saharan Africa, mostly the African savanna, and the identified drivers are human causes (decline in burned area, changes in herbivores density). They explicitly exclude CO2 levels increase as a driver.
>Factorial simulations with multiple global ecosystem models suggest that CO2 fertilization effects explain 70% of the observed greening trend, followed by nitrogen deposition (9%), climate change (8%) and land cover change (LCC) (4%).
Yes, I accept your correction. I accept that the Saharan desert may be greening primarily for other reasons. It seems to have been on a long term trend towards greening irrespective of the Industrial Revolution, and there are other human activities that are greening it. Although, your link does leave open the possibility that rising CO2 explains up to 22% of the greening in the Sahara.
Incidentally the second (earlier) paper is cited by the first (newer) paper, so hopefully they are not in contradiction (since it was merely referenced and not responded to).
This is what I dislike about the politically driven climate "science" or any science corrupted by politics. So much of it is intentionally misleading and many times outright false. They manipulate data, cherrypick time frames or simply outright lie.
The problem is exacerbated by the fact that special interest groups fund these misleading studies and are widely propagated by media with a particular interest.
we have a problem with CO2. The level of CO2 assumed as atmospheric was 275ppm, this assumption was altered to reflect reality, the new reality of atmospheric CO2 accumulation. When gas physiology experiments are conducted it is now proper to assume atmospheric concentrations of 300-350 ppm. these are global average numbers.
Excessive CO2 concentration in the surrounding atmosphere of a phytostoma -the little pores that plants use to admit CO2 into the mesophyll will close up and occlude further gas translocation, this mechanism is very simple -acidification of the cytoplasm of guard cells about the stoma by way of CO2 reacting with cytoplasmic water and making carbonic acid thus reducing the p[H+].
This is a regulatory mechanism as a plant must regulate CO2 assimilation in check with N~ assimilation in accord with developmental state.
if we expose our plants to excessive CO2 then the stoma close up shop until leaf mesophyll allieviates the p{H+} status which we often do with a circulation of atmosphere.
we open a window, or turn on a fan or if we have a LOT of light apx~4000+ Watts/square metre and a signalling frequency of 420nm, the stoma will reopen and we can approach a photosynthetic saturation point - a physiological limit of chloroplasts themselves. there are other particulars such as optimum electrolyte content and composition of root media ; temperature cline and gradient between root and crown, O2 concentration, red, and infrared light intensity , and frequency.
this is a large laundry list so far but when you get used to it its no worse than wiring in for a coding session.
summary is that artificial intervention is required to promote continued uninhibited photosynthesis, and biomass production under a regime of high {> 320ppm} atmospheric CO2 concentration.
Where does all the extra CO2 go to? Our oceans are becoming acidic due to absorbtion of this CO2 and shellfish corals and all other species dependent upon soluted carbonate are having a hard time extracting Ca Carbonate. We are knackering the planet :_{
Anecdote: When I artificially inflated the CO2 in my aquarium, my plants grew like BANANAS. Something like 4x the speed, and about 2x as big leaves, etc. It was quite something amazing.
In terms of geologic history the CO2 levels now are lower then they have been. It's not surprising that plants respond very positively to higher rates of CO2.
And it's been proven to be true many times.
I guess what the study is trying to address is the positive aspect of CO2 rising enough to counter the negative aspect of CO2 rising to the plant biomass.
Plants may grow more easily, also wildfires may burn more easily, areas may get more water, also areas may get less water. Areas may be hotter, but also areas may be colder. The specific results that humanity gets depends on the particular weather patterns that we end up with, which are very difficult to predict, and thus the future holds a great many studies and predictions, most of which will be wrong in their specific results.
This is a subject of interest to scientists, but not to the general public, because nothing being studied here changes the central message in the slightest, which is that we are undoubtedly headed for climate apocalypse and we are accelerating into it rather than decelerating.
Are you aware that this view is completely unsupported by anything resembling conventional science?
The IPCC estimate for equilibrium climate sensitivity for doubling of CO2 (which is about what is plausible) is from a 1.5 to a 4.5 C increase in average global temperature. The low end of 1.5C is not particularly worrying. Certainly not an "apocalyse".
If you weren't aware of this, you should stop confining your reading to alarmist propaganda.
between 250-300 ppm is assumed to be an average normal concentration, this is a reference range compared against the observed concentration of a subject plant tissue. This is a scientifically mandated condition with respect to phytophysiological experimentation. These datum are detected with a simple benchtop infrared spectrum gas analyzer. [IRGA]
An investigation of extreme rigor, or extreme contention must use instruments of higher accuraccy and selectivity, at great expense of course, and exacting grant proposals as a result.
If it's "as close to the nature right before apes became humans", it's easy to answer (though hard to justify on any grounds other than quasi-religous belief in Gaia or something). If it's "planet with more plants and animals" it could be quite different, and any honest scientist would answer it "we don't really know, but here are some considerations..."
I'll point out that the sunniest parts of western Quebec get fewer than 1900 hours of sunshine annually. [1] That's fewer than any point in the contiguous US. Cedars metabolize O2 -- not CO2 -- in the absence of sunlight. That makes this possibly one of the most biased and possibly misleading selections possible for both location and organism under study.
Cities tend to have more air pollution, but the difference in CO2 and O2 are neglible.
I once ran the numbers for O2, which is proportional, and it came out to roughly 10m of high in the atthmosphere. I. e. climb a tree in the countryside and you’re at O2 pressure similar to a city.
Study means little as it takes a specific forest in Canada. We should probably look at Amazonian forests, California's redwoods, India's Vindhyas and Namibia's rainforests too.
The basics of photosynthesis are more or less identical across green plants. All the cool evolutionary shit has been going on in preserving water and capturing light, pointing at CO2 probably not being a limiting factor.
Even the one neat CO2 trick I remember was really a hack to preserve water: some desert plants have a mechanism to store a day’s worth of CO2, allowing them to close pores and prevent evaporation.
Anyway, if you’re looking for a counterexample, I’d switch environments altogether and try again in bacteria, algae, and maybe grasses. While I doubt there would be much of a difference to trees, the first two are at least a few degrees further away from them in the deity’s org chart. All three categories also strike me as possibly being more relevant than trees in terms of total biomass, although that’s just a hunch that may be completely wrong.
Different groups of green plants have significantly different photosynthetic cycles (notably C3, C4, and CAM) which respond very differently to changes in CO2 concentration. For C4 plants (about 3% of plants) the current CO2 concentration is at the point of saturation. C3 plants (85% of plant species, including most trees and grasses, and staple crops such as wheat) have rates of photosynthesis proportional to CO2 concentration to about 1000ppm or so. (The desert plants you mentioned use CAM cycle, but overall their contribution to CO2 consumption is small.)
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[ 3.3 ms ] story [ 29.2 ms ] threadhttps://www.sciencedaily.com/releases/2010/10/101029132924.h...
This is not surprising, as we already know trees and plants consume CO2 to produce cellulose and other plant materials.
This is heavily exploited in greenhouses which are CO2 enrichened to produce better yields - albeit used mostly for growing vegetables, not trees.
( disclaimer I believe in global warming with all my heart)
On top of that, plant growth can be reduced by heat stress. They also have to contend with insects and disease, and may not have good defenses when climate change has brought invasive organisms to the area.
"climate change is generating warmer, drier conditions that could make them grow less in many places"
Overall, conditions are definitely getting warmer on average, and many places are also getting drier, sometimes with occasional very heavy rainfalls that wash away topsoil.
Another factor I didn't mention is forest fires, brought about by drier conditions, as we've been seeing in California.
It's important, because the fertilizer for anti-science attitudes exploited by groups like climate denialists is a false impression of radical flip-flops in science conveyed by popular media which uses exaggerated contradiction to overplay the impact of stories and draw eyeballs.
The real question is whether there will be more biomass and more photosynthesis in response to more CO2, not whether individual trees grow more. The climate skeptics don't say tree trunks will get wider, they say there will be more plant biomass.
And also this is adding in confounding variables and saying more CO2 could change precipitation in certain places, and thus cause lower growth. Other studies that show more growth with more CO2 are using greenhouses to control for confounding variables.
And even if you are trying to answer the question in terms of a holistic analysis, you can't just study one forest in Canada and then make any kind of conclusion.
You'd need to study trees from most of the major forests, and look at the density of the foliage in each.
Speculating that plant biomass might help mitigate global warming doesn't really deserve the label "climate skeptic." It's already confirmed that rising CO2 affects crop growth rates.
For instance, the Saharan desert seems to be greening.
I hadn't heard about that, and my first few Googles came back without any good, definitive articles; do you have more information?
https://www.nature.com/articles/s41467-018-04616-8
The study is about sub saharan Africa, mostly the African savanna, and the identified drivers are human causes (decline in burned area, changes in herbivores density). They explicitly exclude CO2 levels increase as a driver.
https://www.nature.com/articles/nclimate3004
> CO2 fertilization effects explain most of the greening trends in the tropics
It's unrelated to the specific positives and negatives.
Not so much in reasonably well-run parks or woodlands.
source: https://en.wikipedia.org/wiki/Phytoplankton
The problem is exacerbated by the fact that special interest groups fund these misleading studies and are widely propagated by media with a particular interest.
https://www.youtube.com/watch?v=Yze1YAz_LYM
en.wikipedia.org/wiki/Carbon_dioxide_in_Earth's_atmosphere
Excessive CO2 concentration in the surrounding atmosphere of a phytostoma -the little pores that plants use to admit CO2 into the mesophyll will close up and occlude further gas translocation, this mechanism is very simple -acidification of the cytoplasm of guard cells about the stoma by way of CO2 reacting with cytoplasmic water and making carbonic acid thus reducing the p[H+].
This is a regulatory mechanism as a plant must regulate CO2 assimilation in check with N~ assimilation in accord with developmental state.
if we expose our plants to excessive CO2 then the stoma close up shop until leaf mesophyll allieviates the p{H+} status which we often do with a circulation of atmosphere. we open a window, or turn on a fan or if we have a LOT of light apx~4000+ Watts/square metre and a signalling frequency of 420nm, the stoma will reopen and we can approach a photosynthetic saturation point - a physiological limit of chloroplasts themselves. there are other particulars such as optimum electrolyte content and composition of root media ; temperature cline and gradient between root and crown, O2 concentration, red, and infrared light intensity , and frequency.
this is a large laundry list so far but when you get used to it its no worse than wiring in for a coding session.
summary is that artificial intervention is required to promote continued uninhibited photosynthesis, and biomass production under a regime of high {> 320ppm} atmospheric CO2 concentration.
Where does all the extra CO2 go to? Our oceans are becoming acidic due to absorbtion of this CO2 and shellfish corals and all other species dependent upon soluted carbonate are having a hard time extracting Ca Carbonate. We are knackering the planet :_{
And it's been proven to be true many times.
I guess what the study is trying to address is the positive aspect of CO2 rising enough to counter the negative aspect of CO2 rising to the plant biomass.
This is a subject of interest to scientists, but not to the general public, because nothing being studied here changes the central message in the slightest, which is that we are undoubtedly headed for climate apocalypse and we are accelerating into it rather than decelerating.
Are you aware that this view is completely unsupported by anything resembling conventional science?
The IPCC estimate for equilibrium climate sensitivity for doubling of CO2 (which is about what is plausible) is from a 1.5 to a 4.5 C increase in average global temperature. The low end of 1.5C is not particularly worrying. Certainly not an "apocalyse".
If you weren't aware of this, you should stop confining your reading to alarmist propaganda.
If it's "as close to the nature right before apes became humans", it's easy to answer (though hard to justify on any grounds other than quasi-religous belief in Gaia or something). If it's "planet with more plants and animals" it could be quite different, and any honest scientist would answer it "we don't really know, but here are some considerations..."
[1] https://www.currentresults.com/Weather/Canada/Quebec/sunshin...
I once ran the numbers for O2, which is proportional, and it came out to roughly 10m of high in the atthmosphere. I. e. climb a tree in the countryside and you’re at O2 pressure similar to a city.
Even the one neat CO2 trick I remember was really a hack to preserve water: some desert plants have a mechanism to store a day’s worth of CO2, allowing them to close pores and prevent evaporation.
Anyway, if you’re looking for a counterexample, I’d switch environments altogether and try again in bacteria, algae, and maybe grasses. While I doubt there would be much of a difference to trees, the first two are at least a few degrees further away from them in the deity’s org chart. All three categories also strike me as possibly being more relevant than trees in terms of total biomass, although that’s just a hunch that may be completely wrong.
http://theazollafoundation.org/azollas-uses/as-a-co2-sequest...