Plants, both through decay and respiration, are responsible for over half of the world’s annual carbon dioxide emissions.
I mention this fact for one reason and that is to communicate the power of the biosphere upon the atmosphere.
Usually, when discussed in the context of climate change, we talk about the opposite phenomenon, which is the power of the atmosphere on the biosphere. Specifically, the increased growth rate of plants in response to increased levels of atmospheric carbon dioxide.
But that focus on the biological benefits of carbon dioxide has limited our view. How does the biosphere affect the climate? Or, to be more precise, how does the changing biosphere, in response to carbon dioxide emissions, affect the climate?
I would like to propose a new climate feedback for the IPCC. Unfortunately for their organization this is a negative climate feedback. My proposition is a simple one based on these facts:
1) As carbon dioxide levels increase plants need to keep less stomata (pores) open to absorb adequate levels of carbon dioxide
2) With less stomata open plants will lose less water due to transpiration
3) This means less water vapor in the atmosphere – less of a powerful greenhouse gas (WUWT?).
Simply put, higher levels of carbon dioxide, all other things being equal (which we know they aren’t), will decrease levels of water vapor in the atmosphere and therefore the greenhouse effect. This effect will obviously be shown above land rather than the oceans, but then again, the atmosphere above the oceans is already very humid, far overpowering carbon dioxide.
Is this a powerful effect? I don’t know. But keep in mind the first sentence in this article before dismissing its magnitude out of hand. It is certainly something I’d like to see tested under strictly controlled conditions.
The effect would probably be logarithmic in nature, just like the radiative forcing of carbon dioxide is logarithmic, because plants can only grow and store so much water in the limited amount of real estate we have. However, plants do have another interesting, but somewhat predictable response to carbon dioxide – they increase the size of their root systems.
Since their leaves are more capable of supplying the needed carbon the limiting factor for growth becomes the minerals extracted by their roots.
Solution: Grow more and deeper roots.
That is one way the extra water might be stored.
Of course, in his book, A Many-Colored Glass, Freeman Dyson discusses the effects of these more intricate root systems. He postulates that as plants grow more roots and less shoots that their ultimate decay will return more of the carbon to the soil and less to the atmosphere.
That could certainly throw a damper on their multi-century long predictions of atmospheric carbon dioxide levels, especially, and again I defer to Dyson,when he calculates that half of the landmass on Earth would only have increase in thickness by 1/100th of an inch per year in order to absorb every last drop of our carbon dioxide emissions.
Conclusion:
This example was meant to demonstrate how little we know about the climate and, more importantly, the things we didn’t even realize we didn’t know. How many more mysteries are out there befuddling climate models and their predictions?
As simple as this example is, it is still far more complex than the calculations regarding carbon dioxide.
Or is it?
When clouds precipitate away their moisture, releasing heat towards both Heaven and Earth, wouldn’t the carbon dioxide reflect some of that heat back up towards space? Or would those conditions necessarily require a high amount of water vapor in the air which would drown out that effect?
I don’t know. Maybe it is a stupid question – or perhaps just another unknown unknown.
Cheers,
James Padgett
proponents of AGW have to tell me: why did the lesser depression NOT reduce C02 and other greenhouse gasses? Economic activity and manufacturing declined on a global scale not seen since the 30s. The fact that we cannot correlate CO2 (methane) etc to economic activity is a big problem, because it also shows that even if AGW is true curbing this same activity won’t help at all.
Paul Cantwell says:
October 29, 2011 at 5:01 am
“High CO2 levels increases growth but eventually all plants die and the CO2 is released in to atmosphere. No net change.”
You and others pointed out the neglected question in this statement of timing. I just wanted to point out that this is the same principle as employed in the “greenhouse” theory. There, a step change in GHG would result in more energy being retained, though the steady state energy flow in and out would equilibrate. Here, a step change in CO2 results in more carbon sequestered in living plants, though the steady state flow equilibrates.
@dwb says:
October 29, 2011 at 5:49 pm “The fact that we cannot correlate CO2 (methane) etc to economic activity is a big problem”
The reason that there is no correlation to economic activity is that the changes of CO2 due to direct emission are not measurable in comparison to natural changes. Firstly, there are seasonal changes which vary by upto 15ppm due to ocean and vegetation uptake/outgas. Then there are natural events such as volcanoes & forest fires. Then there are natural variations in SSTs. There is no reason to believe that the relatively constant 280ppm of CO2 obtained from proxy data is accurate. For their own selfish interests AGW believers have decided to discard accurate measurements with chemical instruments made by experts including Nobel prize winning chemists and biologists. Have a look at this website http://www.biomind.de/realCO2/realCO2-1.htm and open your mind to some of the complexity of atmospheric changes.
3) This means less water vapor in the atmosphere – less of a powerful greenhouse gas (WUWT?).
———–
Well Rumsfeld overlooked some important additional elements in his taxonomy:
1. The things you know and don’t want to know.
2. The things you dont know and don’t want to know,
Seems to me these additional items were the cause of some much grief in Iraq.
Any how, philosophy aside, I will point out the obvious: the amount of water vapour in the atmosphere is not dependent on just one process. It depends on the BALANCE of 2 process. Evaporation/transpiration and precipitation
If you get more evaporation/transpiration the balance is maintained by more precipitation.
So according to the suggested hypothesis more CO2 means less transpiration and therefore less rain. To get this hypothesis to work in the way suggested it would need to show that there would develop an imbalance between the two processes.
P.S. The writer assumes the IPCC has not considered this. They may or may not but this smells like an assumption.
cementafriend says:
October 29, 2011 at 6:32 pm
…. For their own selfish interests AGW believers have decided to discard accurate measurements with chemical instruments made by experts including Nobel prize winning chemists and biologists. Have a look at this website http://www.biomind.de/realCO2/realCO2-1.htm and open your mind to some of the complexity of atmospheric changes.
___________________________________
The whole CO2 record stinks like bad fish!
The biggest stink in my mind is the ASSumption that the “background” CO2 is uniform in the atmosphere.
This ASSumption allowed them to throw out all the high readings from the historical wet chemistry record and cherry pick the low records. This particular pdf looking at the dogma and politics behind the 70 years of CO2 measurement as well as the science. It is a very interesting read. http://www.co2web.info/ESEF3VO2.pdf from the website: http://www.co2web.info/
This is the part that really gets my goat.
The acknowledgement in the paper by Pales & Keeling (1965) describes how the Mauna Loa CO2 monitoring program started:
“The Scripps program to monitor CO2 in the atmosphere and oceans was conceived and initiated by Dr. Roger Revelle who was director of the Scripps Institution of Oceanography while the present work was in progress. Revelle foresaw the geochemical implications of the rise in atmospheric CO2 resulting from fossil fuel combustion, and he sought means to ensure that this ‘large scale geophysical experiment’, as he termed it, would be adequately documented as it occurred. During all stages of the present work Revelle was mentor, consultant, antagonist. He shared with us his broad knowledge of earth science and appreciation for the oceans and atmosphere as they really exist, and he inspired us to keep in sight the objectives which he had originally persuaded us to accept.”
Is this the description of true, unbiased research?
The annual mean CO2 level as reported from Mauna Loa for 1959….“ http://www.co2web.info/ESEF3VO2.pdf
Sounds to me more like enviromentalists looking for data to fit their pet theory.
And here is the actual a description of how they REJECT readings at Manua Loa.
“4. In keeping with the requirement that CO2 in background air should be steady, we apply a general “outlier rejection” step, in which we fit a curve to the preliminary daily means for each day calculated from the hours surviving step 1 and 2, and not including times with upslope winds. All hourly averages that are further than two standard deviations, calculated for every day, away from the fitted curve (“outliers”) are rejected. This step is iterated until no more rejections occur.</b. http://www.esrl.noaa.gov/gmd/ccgg/about/co2_measurements.html
As Segalstad’s website states:
”At the Mauna Loa Observatory the measurements were taken with a new infra-red (IR) absorbing instrumental method, never validated versus the accurate wet chemical techniques. Critique has also been directed to the analytical methodology and sampling error problems (Jaworowski et al., 1992 a; and Segalstad, 1996, for further references), and the fact that the results of the measurements were “edited” (Bacastow et al., 1985); large portions of raw data were rejected, leaving just a small fraction of the raw data subjected to averaging techniques (Pales & Keeling, 1965). http://www.co2web.info/ESEF3VO2.pdf
Yes Ferdinand Engelbeen, I am well aware that Jaworowski is persona non grata for daring to criticize the Ice Core chemical analysis. However I have spent forty years tearing my hair out over the issue of the batch is “well mixed” for both solids or liquids. That was for “simple” situations with no more addition and active mixing. If there is one thing I have learned it is chemicals DO NOT mix as well as most believe. I have been FIRED for proving the erratic results were due to the poor mixing of the batch and not due to the analytical method.
That said, How the heck can ANYONE think that CO2 with multiple sinks and sources is “well mixed”???
For example:
Volcano Outgasing of CO2. “The primary source of carbon/CO2 is outgassing from the Earth’s interior at midocean ridges, hotspot volcanoes, and subduction-related volcanic arcs.” http://www.columbia.edu/~vjd1/carbon.htm
The Eyjafjallajokull eruption and its effects on Europe shows just how “well mixed” the air borne particles were and how rapidly they “mixed”
This study gives a feel for what plants do to the CO2 levels
“…The CO2 concentration at 2 m above the crop was found to be fairly constant during the daylight hours on single days or from day-to-day throughout the growing season ranging from about 310 to 320 p.p.m. Nocturnal values were more variable and were between 10 and 200 p.p.m. higher than the daytime values….” Carbon dioxide measurements above a wheat crop, 1. Observations of vertical gradients and concentrations, C.S.I.R.O., Division of Atmospheric Physics, Aspendale, Vic. Australia
So you are talking about as much (or perhaps more ) than a 200ppm day night difference and it happens FAST as soon as air movement bring the CO2 into the area around the plant.
CO2 depletion
“Plant photosynthetic activity can reduce the Co2 within the plant canopy to between 200 and 250 ppm… I observed a 50 ppm drop in within a tomato plant canopy just a few minutes after direct sunlight at dawn entered a green house (Harper et al 1979) … photosynthesis can be halted when CO2 concentration approaches 200 ppm… (Morgan 2003) Carbon dioxide is heavier than air and does not easily mix into the greenhouse atmosphere by diffusion… Source
Note the 200ppm for halting photosynthesis. I had in my early notes “200 pm CO2 trees starve” SOURCE: http://biblioteca.universia.net/ficha.do?id=912067
but the link no longer works… Now all the searches turn up papers showing 180 ppm or lower….HMMMmmmm Looks like a bit of editing so the 180 ppm in the Ice Core data doesn’t stink so bad.
What is really really interesting is Barrow 1947-1948 data at 420 ppm! (average of 330 samples) It is noted that the Keeling samples (1972 to 2004) are transported from Barrow Alaska to California before they are analyzed. http://www.biokurs.de/eike/daten/leiden26607/leiden6e.htm
Beck’s site: http://www.biokurs.de/eike/daten/leiden26607/leiden9e.htm
I’m not sure how this impacts the hypothesis, but I believe it has been found the the root hairs in most root systems are actually in symbiotic collaboration with even more extensive (and massive?) networks of fungi, which actually do most of the heavy lifting wrt mineral extraction, water collection, etc.
Perhaps a multiplier there?
http://www.letterdash.com/HenryP/henrys-pool-table-on-global-warming
look again carefully at my tables quoted above and if you really take some time to study them you can easily figure it all out for yourself:
1) first the so-called ”global warming” is not global at all.
In the Southern Hemisphere (SH) there is almost no warming. Clearly, you can see a big difference in the results for means between NH and SH? Check out these two weatherstations’ results from the antarctic.
http://www.nerc-bas.ac.uk/icd/gjma/amundsen-scott.ann.trend.pdf
http://www.nerc-bas.ac.uk/public/icd/gjma/vostok.ann.trend.pdf
They are remarkably flat.
But now, how can that be? We know from real science and experiments that the CO2 is distributed everywhere exactly the same. So, if increased CO2 were to be blamed directly due to it causing an increased greenhouse effect, should not the warming be the same everywhere in the world? So, we conclude (again) it never was the increase in GHG’s that caused any warming.
2) If you look in Argentina (where there was considerable de-forestation) you find severe cooling. If you look at Norway (where there is much increased forestry) you find warming.
3) the fact that SH has little landmass and that the NH has a lot of landmass is an another indicator that should give a clue.
4) we also know that there have been reports, e.g. from the Helsinki university that there has been increased vegetation in the past decades, especially in the NH…..
for more proof that earth is greening especially in the northern hemisphere, look here:
http://wattsupwiththat.com/2011/03/24/the-earths-biosphere-is-booming-data-suggests-that-co2-is-the-cause-part-2/
…..Did you figure it out?
Some extra warming (that which some scientists have identified as being on top of that which is natural) is caused by …… more vegetation!!! Now we sit with one problem: Part of that “problem” of the extra vegetation could be caused by people wanting more trees and forests and gardens and the increase in carbon dioxide in the atmosphere acts as a fertilizer and accelerator for growth..………the circle is complete….now what?
LazyTeenager says:
October 29, 2011 at 6:51 pm
P.S. The writer [James PadgetT] assumes the IPCC has not considered this. They may or may not but this smells like an assumption.
Whatever, Lazy, but maybe now they should ‘reconsider’ it via a “mass balance” approach?…you know, given their pristinely “scientific” drive to finally be able to get one GCM prediction right? //Not!
p.s., Lazy, you aren’t going to learn much by just sitting around sniffing yourself or by repeating memes floating around within the CO2 = CAGW Cult’s pleroma – which I assume is the same one giving you the , er, “universe” of your Iraq War “facts”.
FWIW, the Japanese satellites seem to show more CO2 / methane coming from 3rd world locations with a lot of plants. I have to wonder if “jungle rot” is more important than my car in net CO2 production. And if all those phone books in landfill sites constitute “sequestration” 😉
http://chiefio.wordpress.com/2011/10/31/japanese-satellites-say-3rd-world-owes-co2-reparations-to-the-west/
In any case, what we don’t know about plants looks to dominate global CO2 production / consumption levels.
Please don’t fail to consider that CO2 isn’t all released when a plant dies. Microbial life increases dramatically, and 2nd growth over grows a still decomposing tree structure.