Starving Plant Life

In my last post, Boogie-man Gas, I talked about CO2 and the controversies surrounding this trace gas.  I also pointed out to evidence that CO2 has been a beneficial gas, and not the pollutant that most people think it is.

Still, with headlines such as these (Scientists call for action to tackle CO2 levels,[1] and New Milestone for CO2 Levels: Mauna Loa Observatory Records 400 PPM [2]), it makes me wonder if the scientific process has somehow broken down when one group of scientists state unequivocally that CO2 will cause a runaway greenhouse effect, killing all living things with excessive heat, while another group states, also just as vehemently, that a lack of CO2 will cause plants (and therefore, animals) to die, and usher in a new ice age which will freeze everything for hundreds of thousands of years.

Do these scientists even bother to read each others’ hypotheses and studies, or do they all just argue for the sake of argument’s sake?  Is CO2 really bad for us, or is it crucial for our existence?

As a Taoist, I have a feeling it’s somewhere in between the two extremes, but although I may stake my claim as a Taoist, I certainly cannot stake my claim as a scientist because I have not yet earned my lab coat.  So I did the next best thing.  I donned on my Questioning Hat and transformed myself into my alter-ego, the mystical, all-knowing, Blonde Tao Witch.

I do this, not because I am strange (OK, I am a little strange, but not as strange as you think), but because I have found out something important about my mental processes.  By temporarily donning on this hat, I suspend my normal daily rational thinking brain for awhile as I explore other ideas and options without the urge to shoot them down and stomp them into the ground for daring to challenge what I hold as the shining truth.

So then, to my alter-ego, I posed the following two questions having to do with CO2′s properties:

• What is the controversy surrounding the heat absorbency property of CO2?  Why is it not tracking properly with temperature changes of Earth?
• What is the controversy behind CO2′s role in photosynthesis?  Is there too much CO2 in there air, or is there a lack of CO2 in the air?

I’m going to tackle the heat absorbency property of CO2 first, as that is basic high school chemistry and fairly straightforward to describe.  Most of the energy from the sun is emitted in wavelengths shorter than 4,000 nanometers (.000004 meters).  Earth absorbs some of the heat from the Sun and then reflects some of it back as light and the rest as heat.

Even though CO2 doesn’t absorb heat energy from the sun because solar wavelengths are too short for it to absorb, it does absorb some of the heat energy released from Earth.  It can do so because once Earth has absorbed the Sun’s energy, in the process of internalizing the energy, she changes its wavelength.  The heat energy released from the earth is discharged in wavelengths longer than 4,000 nanometers, which allows CO2 to absorb energy that falls within that mid-infrared range of 10,600 nanometers.

When a molecule of carbon dioxide absorbs Earth heat energy, it goes into an excited unstable state and can only become stable again by releasing its absorbed energy.  Some of this released energy returns to Earth and some is expelled out into space.  Unfortunately, carbon dioxide allows the entire range of Solar wavelengths into Earth’s atmosphere, but only allows the range of Earth wavelengths that it can absorb (10,600 nm), back out again.  This causes a build-up of the infrared wavelengths that are less than 10,600 nm, thereby causing the Earth to retain more and more of the sun’s warmth.  At some point, this warmth is expected to exceed that temperature which is able to support life.

I’m going to pause at this point and continue onward with photosynthesis.

The process of photosynthesis is fairly straight forward.  Plants get their food from sunlight by chemically altering carbon dioxide and water to convert that sunlight to storable chemical energies.  They give off oxygen as a waste product, and with good reason—oxygen is a highly toxic mutagenic gas that causes oxidation of various metals.  Interestingly enough, animals have evolved to utilize this waste product, and even to require it to maintain the combustion engine that make up all animal life, both above and below the water.  (As an aside, even as I ponder over this simple chemical loop, I can’t help but notice that we use this flammable gas to burn away our brief existence, cell by cell, until we can no longer keep up the pace of cell-burn versus cell-production.  Once we can no longer keep apace with the burn-rate, we simply die).

In essence, animals (including humans) complete the loop of life, taking in the poisonous oxygen, converting it, and then releasing the life-giving carbon dioxide so that plants can live.  Plants need us to live just as much as we need them to breathe.  Without carbon dioxide, plants cannot continue their process of photosynthesis.

Why then, is there so much discrepancy and divergency of opinion in something as basic as the effects of CO2 on the Earth and its denizens?  Isn’t there solid evidence that green plants need CO2 for the processing of photosynthesis?  Shouldn’t we at least try to figure out how much CO2 plants really need before we try to remove what we think are unnecessary and excessive amounts of CO2 from the air?  That just seems to me to be prudent, but who am I to suggest something this obvious?

Lucky for me, I don’t have to figure this part out.  There are already studies that have been done by several groups of researchers, and they found that there are three most likely causes of plant death:  insect-infestations and disease, lack of water, and carbon-dioxide starvation. [3]

This is my opinion on these three causes of plant death.

Insect attacks and disease are natural occurrences that have been going on for as long as there has been life on Earth.  It is part of the cycle of life and cannot, therefore, be considered a tragic occurrence in any way shape or form.  It is one of the ways that evolution is able to work its magic, picking and choosing the life forms that can best adapt to its ever-changing environment.

The lack of water occurs in cyclical fashion throughout Earth’s billions of years of existence due to the cyclical nature of ice ages.  Simply put—when it is cold, all the water is locked up in the polar caps and the glaciers, causing a lack of water everywhere else.  During these dry cold spells, there is more land which is exposed to dry air because there is less water to cover it.

When the relatively short interglacials come around again, everything warms back up and the ice melts, releasing its cache of water and causing low-lying areas that had previously been above water to become submerged.  It also allows for arid, dessert areas to become green and wet and fertile (ergo parts of north east Africa and Mesopotamia).  This is also a normal Earth cycle and not some horrible tragedy that is about to befall humanity.  Over and over again, Earth’s message has always been clear.  Don’t live on sand bars and don’t live near coastlines as those are the areas in flux each time she goes through her cycles.

Last on that list is carbon-dioxide starvation.

Say what?

Did I read that right?  Are our trees starving for CO2?   If the amount of CO2 that we humans have been recklessly spewing into the air all these decades is not enough for trees to grow, what then is enough?

Interestingly enough, botanists already have the answer to this question.

Below 200 PPM, plants do not have enough CO2 to carry on the photosynthesis process and essentially stop growing. Because 300 PPM is the atmospheric CO content, this amount is chosen as the 100% growth point. You can see from the chart that increased CO can double or more the growth rate on most normal plants. Above 2,000 PPM, CO2 starts to become toxic to plants and above 4,000 PPM it becomes toxic to people. [4]

At this point, we don’t really have to worry about reaching that toxic 2,000 ppm.  As of May 2013, CO2 levels almost reached the 400 ppm (parts per million) mark [2].  That’s higher than it has been in a very long time, but from the plant’s perspective, it’s nothing to write home about.  In fact, according to H. Leighton Steward, plant life on Earth is actually close to starving.

At Current CO2 Concentrations, Plants are Close to Starving.  Acting in concert, the several phenomena described in the preceding subsections, as well as other phenomena possibly yet unknown, typically allow the growth-enhancing effects of atmospheric CO2 enrichment to be expressed in the face of severe resource deficiencies.  But what happens in the case of “carbon starvation,” when the air is deficient in CO2?

Because CO2 is the basic “food” of essentially all plants, the more of it there is in the air, the bigger and better they grow; and as the air’s CO2 content declines, so too do plant growth rates decline.  And when a critically-low CO2 concentration is ultimately reached, starving plants lacking sufficient CO2 – like starving people lacking sufficient food – actually die, as indicated in the figure below, where plant death occurs when dry weight production falls to zero. [5]

I wasn’t sure I read him correctly because I have been told all my life that CO2 was TOO ABUNDANT in the atmosphere.  And yet, here is this scientist saying that the plants growing on Earth are dying because they are starving for CO2.  Indeed, it is also the reason why people add extra CO2 into commercial greenhouses—because they know that plants need more CO2 for maximum production.  There is even a term for it.  It’s called CO2 fertilization. [6]

Picture on the right: Empirical Data. Growth of 21-day-old rice and S. viridis seedlings at different ambient CO2 concentrations ranging from 30 to 800 parts per million. NOTE: The very last set of pots on the extreme right is out of sequence. They are for 390 ppm, while the next to last pots are for 800 ppm.

Graph on the left:  Modeled Data:  Modeled changes in CO2 assimilation rate in response to changes in leaf intercellular CO2partial pressure for C3 and C4 photosynthesis and for a hypothetical C4 rice. Curves 1, 2, and 4 have Rubisco levels typically found in a C4 leaf (10 μmol m−2 catalytic Rubisco sites). Curve 3 shows a typical response for C3 leaves with three times the Rubisco level of C4 leaves. Curve 1 shows the response of a C4 leaf with C4 Rubisco kinetic properties. Curve 2 models how a C4 leaf with C3 Rubisco kinetic properties would respond (a hypothetical C4 rice with C3 Rubisco kinetics). The comparison of these two curves shows the increase in CO2 assimilation rate achieved with C4 compared with C3 Rubisco kinetic properties within a functional C4 mechanism. Arrows to curves 1 and 3 show intercellular CO2 partial pressures typical at current ambient CO2 partial pressures for C4 and C3photosynthesis. To generate the curves, model equations were taken from (11) and comparative Rubisco kinetic constants from (12). (B) [Reference numbers per source.]

Source: Susanne von Caemmerer, W. Paul Quick, and Robert T. Furbank (2012). The Development of C4 Rice: Current Progress and Future Challenges. Science 336 (6089): 1671-1672.

While I do appreciate the serious efforts of all scientists to find ways of maintaining the Earth in liveable conditions for its seven-plus billion denizens, I am not convinced that CO2 is the driving factor behind global climate change because, unfortunately for us, historical data regarding global temperatures that scientists were able to extract from tree rings and ice cores doesn’t match up with computer model predictions.  I say ‘unfortunate’ because if it was as simple as removing CO2, we would be able to figure out how to fix the situation sooner rather than later.  Sadly, from everything that I have read, including all the data points that I have been able to gather from scientists of all fields, I am starting to believe that global climate change it is NOT something that is fixable by human intervention and it is NOT tied to the rise and fall of CO2 at all.

Global climate change, from what I am able to gather, is directly affected by several great heavenly cycles of the solar system.  Some of these cycles are Earth-related and others are Solar cycles which impact Earth due to her dependence on the Sun for radiant energy.  When these cycles overlap, we get major global climate change.  I wrote about one of those cycles in a previous post, Winter In July.  That post talked about Earth’s precession, and although it is an important cycle, it is not the only one that Earth has.  There are other cycles, and they all impact global climate and temperature in varying degrees.  I will go into the other Earth cycles in my next few postings, and then I will get into the Solar cycles and how that affects us.

…

1.  Scientists call for action to tackle CO2 levels

2.  New Milestone for CO2 Levels: Mauna Loa Observatory Records 400 PPM

3.  New Studies Point to ‘Carbon Starvation’ as a Cause for Tree Mortality

4.  Carbon Dioxide Enrichment Methods

5.  Plantsneedco2.org

6.  Growing Greener Tomatoes:  First US Greenhouse with Onsite CO2 Fertilization