Tuesday, October 25, 2011

The Azolla Alternative

The recent pre-publication of four papers by the Berkeley Earth Surface Temperature team has raised the level of furor in at least some venues over the future (if any) of the IPCC and how to handle the issues of rising CO2.  I've discussed this in another venue, along with my confidence in remediation (CO2 draw-down) as preferable to expensive efforts at mitigation.

I'm going to put a few numbers behind this statement:
With the right approach, IMO, we could start a process today that would probably result in the ability to draw down CO2 within a 5-10 year active time, using (bio-)technology that might mature within 20 years.
Now, let's start with assuming a 100ppm (parts per million) draw-down, which would be equivalent to reducing our current level of ~400ppm to 300ppm, equivalent to a date prior to 1960. Just how much carbon would we have to remove from the atmosphere?

The density of the atmosphere at sea level is about 1Kg/M3, and the pressure is roughly 10 tons/M2. Now, the average molecular weight of air is about 29, while the average molecular weight of CO2 is about 44. Parts per million are calculated by volume, which corresponds to number of molecules.

So 100ppm CO2 would weigh (44/29)*(100/1,000,000)*10,000Kg/M2 = ~1.5Kg/M2. The carbon would be about 12/44 of that, or about 414g/M2, or 414 tons/Km2. The Earth's surface area is about 5.1*108Km2, which adds up to 211.17GTon carbon to be removed. Given the nuclear connotations of "gigaton", I'm going to call it Petagrams (Pg), which is common in carbon literature.

The Azolla Event

About 50 million years ago (MYA), there occurred an event of global importance called the Eocene Azolla event. Evidence suggests it began around 49.3MYA, lasting until around 48.1MYA, thus lasting about 1.2MY.[1] In this event, it appears that fresh water from Arctic rivers formed a layer over the surface of the heavier salt water, and the entire Arctic (or large parts of it) experienced a massive bloom of a fern called Azolla.

Azolla is an intriguing plant, actually a symbiosis between a secondarily degenerate fern (Azolla sp.) and a blue green algae (Anabaena azollae). It's just a few inches in size, and floats entirely on water, without normally anchoring. It's one of the fastest growing plants known, capable of producing 25-90gm/day/M2.[2] It normally expands vegetatively, although under appropriate circumstances it will reproduce sexually.[3]

The speed with with the Eocene Azolla grew appears to have been such that it reduced the atmospheric level of CO2 from 3500ppm to 650ppm,[4] probably within that small 1.2 million year stretch.[5] Thus, it makes a great candidate for drawing down CO2.

Let's do some more numbers. The circumstances under which Wagner grew Azolla Nilotica were probably not as optimized as could be done with modern technology, and I'm going to assume that harvesting processes could keep the Azolla growing at maximum rate continuously. 90 gm/day/M2 is equivalent to the same number of tons/Km2/day, multiplied by 360 gives 32,400 tons of biomass/Km2/year. Carbon content for various European strains of Azolla ranged from 37-42%.[6] I'm going to assume 40% (by weight) coming to 12,969, or roughly 13Kilotons Carbon/Km2/year.

Technology

Now comes the technology. I'm going to assume for the moment that within a decade or two we have the technology to float a layer of fresh water on top of salt for very large areas. Later I'll go into possible methods, but for the moment let's just assume one million square kilometers, less than 1/7th the area of Australia. This works out to 13 Pg (=gigatons)/year. Remember above we said that we have ~212Pg to remove in order to draw-down 100ppm? Dividing 212 by 13 gives about 16.3 years. Double this, and we're down to 8.2 years, triple it and we're down to about 5.5 years. And that's still less than half the area of Australia.

I'm not going to go into detail regarding methods. Fresh water is lighter than sea water at the same temperature, which explains how the fresh water managed to stay separate from underlying salt water during the Azolla Event. The difference is only about 2.5%, however, which is pretty small. The lower levels of the Arctic appear to have been anoxic,[7] in the same way the Black Sea is today.

It's remotely possible that simply floating a layer of fresh water on top of salt water might work, but I'm going to assume not. Given this, the easiest way I see to handle it is with an intermediate layer of some viscoelastic material, with a density intermediate between fresh and sea water. More material intensive, but perhaps cheaper, might be a sort of "air mattress" with a lot of internal tensile stiffening. Another option would be to maintain a layer of pressurized air topped with a stiff but slightly flexible layer, with water above it.

Obviously, all these options would require a good deal of engineering and development. However, consider the difference between 1991 and today. No cell phones (except huge experimental clunkers that only worked in a few areas). The Internet was just getting set up, and mostly just existed in educational environments. When we look at the difference just 20 years has made, there's no good reason to suppose we couldn't do this.

The total amount of the world's good quality agricultural land is around 16.5 million Km2.[8] I've discussed using 3 million Km2. The total amount of lower quality agricultural land in the world is around 43.7 million Km2. This has been described in the following terms:
If there is a choice, these soils must not be used for grain crop production, particularly soils belonging to Class IV. All three Classes require important inputs of conservation management. In fact, no grain crop production must be contemplated in the absence of a good conservation plan. Lack of plant nutrients is a major constraint and so a good fertilizer use plan must be adopted. Soil degradation must be continuously monitored. Productivity is not high and so low input farmers must receive considerable support to manage these soils or be discouraged from using them. Land can be set aside for national parks or as biodiversity zones. In the semi-arid areas, they can be managed for range. Risk for sustainable grain crop production is 40-60%.[9]
As our population expands, methods to manage, control, and maintain these lands will become increasingly expensive, relative to more basic types of agriculture. At the same time, technology to manage activities on the water will be coming down in cost. Very likely, they'll meet at some point, at which point it will be cheaper to build new prime agricultural land floating on the ocean than continue using poorly suited terrestrial land. Long before this happens, simple technologies like that necessary for the Azolla Alternative will have become cost effective.

I'm going to leave economic and political issues for another post.

Refs:

Bocchi, S., Malgioglio, A. (2010) Azolla-Anabaena as a Biofertilizer for Rice Paddy Fields in the Po Valley, a Temperate Rice Area in Northern Italy International Journal of Agronomy Volume 2010 (2010), Article ID 152158, 5 pages doi:10.1155/2010/152158

Eswaran, H., Beinroth, F., Reich, P. (1999) Global Land Resources & Population Supporting Capacity Published in: Eswaran, H., F. Beinroth, and P. Reich. 1999. Global land resources and population supporting capacity. Am. J. Alternative Agric. 14:129-136.

Pearson, P.N., Palmer, M.R. (2000) Atmospheric carbon dioxide concentrations over the past 60 million years Nature 406 (6797): 695–699. doi:10.1038/35021000. PMID 10963587

Speelman, E., Damsté, J.S., März, C., Brumsack, H., Reichart, G. (2010) Arctic Ocean circulation during the anoxic Eocene Azolla event Geophysical Research Abstracts Vol. 12, EGU2010-13875, 2010

Speelman, E.N., Van Kempen, M.M., Barke, J., Brinkhuis, H., Reichart, G.J., Smolders, A.J., Roelofs, J.G., Sangiorgi, F., de Leeuw, J.W., Lotter, A.F., Sinninghe Damsté, J.S. (2009) The Eocene Arctic Azolla bloom: environmental conditions, productivity and carbon drawdown Geobiology (2009),
7, 155–170 DOI: 10.1111/j.1472-4669.2009.00195.x

Wagner, G.M. (1997) Azolla: A Review of Its Biology and Utilization The Botanical Review 63(I): 1-26, January-March 1997

Zahran, H.H., Abo–Ellil, A.H., Al Sherif, E.A. (2007) Propagation, taxonomy and ecophysiological characteristics of the Azolla-Anabaena symbiosis in freshwater habitats of Beni-Suef Governorate (Egypt) Egyptian Journal of Biology, 2007, Vol. 9, pp 1-12 Read more!

Tuesday, September 13, 2011

Laccognathus embryi

I have to share this, although I suspect everybody already has read about it, or soon will. Here's the headline and lead paragraph I read (From Google News):

375M-Year-Old Predatory Fish Prowled North America Before Backboned Animals
A new species of large predatory beast of a fish, packing a powerful bite, was already on the prowl in ancient North American waterways before backboned animals existed, researchers say.


After some searching, I found this:

Predatory Fish Once Prowled Ancient Canadian Arctic

A species of fish previously thought to have only existed in Eastern Europe once prowled ancient North American waterways during the Devonian Period, before backboned animals existed on land. [my emphasis]


I just can't think of a comment fit to publish even on a blog. *Sigh!* Read more!

Tuesday, August 30, 2011

3 Chimpanzee Movies

From a couple of articles by Kimberley J. Hockings, et als.: Chimpanzees Share Forbidden Fruit, and Road crossing in chimpanzees: A risky business.

Crossing a Road (movie): Note how the first male out stands watch. AFAIK the 2nd and 3rd are young males: apprentices.

Crop Raiding (movie)

Sharing raided food (movie)

I don't have time to discuss the subject at the moment, but I'm guessing these will be interesting. Compare this "hunter’s anecdotal report" quoted from Guillot, 1956, in Dr. Hockings doctoral thesis Human-chimpanzee coexistence at Bossou, the Republic of Guinea: a chimpanzee perspective:
"I remember one strange encounter I had in the jungle. A troop of chimpanzees was crossing the jungle path ahead of me, an old male, the leader, stood glaring at us from a distance of a few paces. At intervals he intensified his gruntings to hurry up the rest of the troop, cursing the stragglers. The last chimpanzee to cross was a terrified female. Suddenly the big male gave a bound towards her, seized her and shook her and grunted at her something we could not interpret. Whatever it was, it forced her to turn back into the bush. She reappeared a moment later, and now, clinging to her back with both hands and feet, was a grimacing little baby chimpanzee, which in her terror she had abandoned. Then she leaped into the air with her baby in her arms and disappeared among the foliage of the trees. All was now in order, and the old male gave a couple of triumphant grunts, made a gesture as much to say that the path was free for me, and disappeared into the jungle, the last of his troop.”
She calls it "largely anthropomorphic and likely to be somewhat embellished, but serves to highlight the protective nature of the adult male chimpanzee during this high-risk encounter." I wonder how embellished it actually was. Read more!

Tuesday, June 7, 2011

Neurology and the Soul

I've just found time to read John Wilkin's Is the soul something we should be agnostic about?, as well as two posts he links to: Sean M. Carroll's Physics and the Immortality of the Soul and PZ Myers' Ain't no heaven, ain't no afterlife of any kind, either, say the physicists.

Are you folks kidding me? Or has physics actually discovered and verified an underlying source of determinism while my back was turned? Or is everybody missing at least one part of the big picture? (Or am I imagining things?)

The underlying assumption in all these arguments is that there's no way for something going on in "spirit space" to interact with the real world. Now, I don't claim to be the physicist Sean M. Carroll is, in fact my understanding is amateur and older than decoherence. But my understanding is that, in practical terms, quantum indeterminacy still reigns, at least with regard to even theoretically predicting the outcome of local wave function collapse (or, if you wish, "decoherence").

Consider the situation where an action potential arrives at a synapse, and releases a certain amount of neurotransmitter. The number of molecules of neurotransmitter vary within a small range due "indeterminacy", and the number of receptors for that neurotransmitter that are actually active will also vary, depending on many factors within the cell, many of them also slightly "indeterminate". Thus the actual size and shape of the current resulting from that action potential can vary within small limits. (In fact, even with a fixed number of molecules of neurotransmitter and receptors, there will be some variation in current due to indeterminacy of position of each neurotransmitter molecule while diffusing across the synaptic gap.)

Now, let's suppose that that one action potential is just on the border of causing the receiving neuron to fire an action potential. That is, given the current (heh) condition of the nearby dendritic arbor, the amount of current necessary to cause an action potential to fire is right in the middle of the potential variation (in current) due to indeterminacy.

Does the neuron actually fire? Or does it end up in a state of superposed states of firing and not firing? Well, I think we can state that it fires, that is that decoherence has taken place. Do we actually know the source of all the information involved in the decoherence?

We don't, of course. People who state that decoherence has proven that everything happening on the quantum state is completely deterministic are simply projecting their own prejudice (i.e. religious convictions) on what is still a highly controversial field. There's plenty of room in those little wave function collapses for huge amounts of information to flow into our universe.

We certainly don't know how many of the neurons in our brains actually balance on the head of this pin. For that matter, the calculations that go on in the dendrites to integrate the information from the current flows in the synapses also depend on distributed molecules of receptors, most of which open and close "randomly" depending on quantum processes that contain "indeterminacy".

So, is it possible for:
some sort of blob of spirit energy that takes up residence near our brain, and drives around our body like a soccer mom driving an SUV?

as Sean M. Carroll mocks and PZ Myers quotes? Well, conceivably, if we assume these "spirit" people are using the word "energy" metaphorically. (Which they probably are since they don't understand physics or thermodynamics well enough to use it in a technical sense.)

Of course the blobs of "spirit energy", actually some sort of informational phenomenon, would have to have some way of predicting the outcomes of all their interventions in these decoherences. Perhaps time and information work differently in "spirit space". Perhaps they can "see" the potential outcomes of different combinations of interventions directly, rather than having to compute it with incredibly powerful modeling. In the same way, perhaps, that a man riding a balloon can see the road ahead without having to rely on asking passing strangers about it.

Of course, this is all very interesting, and would make a great "magic system" for a fantasy novel, but is there any evidence, no matter how tenuous, that such a thing might be so?

Actually yes. Compared to other anthropoid species, humans have a third or so higher ratio of glial cells to nerve cells in at least on area of the dorsolateral prefrontal cortex (area 9L):
Based on the nonhuman species mean LS regression, humans displayed a 46% greater density of glial cells per neuron than expected.

[...]

From this prediction, glial density in humans fell within the 95% PIs (observed log glial density = 5.19; predicted = 5.02; upper PI = 5.40, lower PI = 4.63) and represented 32% more glia than expected.[1]
Perhaps the human brain has evolved, over the last few million years, to be "ridden" by a "blob of spirit energy", and supporting the receipt of information from the blob is what requires the extra glial activity.

Of course, the actual increase isn't all that great, and:
The human frontal cortex displays a higher ratio of glia to neurons than in other anthropoid primates. However, this relative increase in glia conforms to allometric scaling expectations, when taking into consideration the dramatic enlargement of the human brain. We suggest that relatively greater numbers of glia in the human neocortex relate to the energetic costs of maintaining larger dendritic arbors and long-range projecting axons in the context of a large brain.[1]
So this "evidence" is highly tenuous. But that's very different from saying it would require a new formulation of natural law.

So when PZ Myers says:
The biologists' perspective, which is a little less fundamental, is simply that there is no identifiable 'receiver' localized in the brain (no, not even the pineal gland, as Descartes believed), distributed physiological activity is associated with thought, and injury, disease, and pharmacology can all profoundly influence the mind. Furthermore, the way the brain works involves trans-membrane ion fluxes and synaptic activity — it's all electrochemistry and biochemistry. In addition to that new physics, we'd need a new chemistry to explain how spirit interacts with neurotransmitters or gene expression or protein phosphorylation.
Well, we don't need "new" physics (although we would need to add some stuff to the one we have) and we don't need new chemistry. The receiver is distributed, just like the physiological activity.

Despite what atheists would like to believe, there are still big holes in our scientific understanding of the world; big enough to drive the biggest spirit.

For the moment, I'd recommend agnosticism.


Notes:

1. Chet C. Sherwood, Cheryl D. Stimpson, Mary Ann Raghanti, Derek E. Wildman, Monica Uddin, Lawrence I. Grossman, Morris Goodman, John C. Redmond, Christopher J. Bonar, Joseph M. Erwin, and Patrick R. Hof Evolution of increased glia–neuron ratios in the human frontal cortex PNAS September 12, 2006 vol. 103 no. 37 13606-13611 doi: 10.1073/pnas.0605843103 Read more!

Sunday, June 5, 2011

Evolutionary Theory for Creationists

I was recently informed by a creationist that "evolution is a lie!" I went to the trouble of thinking through and writing down my response, so I thought I'd share it with my readers. I created it as a .PDF so clean copies can be printed for creationists who "don't get" the internet. If you want to print it, or save it as a .PDF, click on the word "File" under "Google docs" over at the top left, and select "Print(PDF)".

Evolutionary Theory for Creationists

Can you tell it was written by an agnostic?

This document is entirely original with me, except that the "old saying" I heard somewhere: I don't remember where, I don't know who said it first, and it's something of a paraphrase anyway. With this post I'm putting this document in the public domain as a public service: feel free to copy, modify, and use the result as you please, for profit or not. (Of course, if you claim credit, you'll be "guilty" of plagiarism, but not (AFAIK) theft.) Credit would be nice, but I don't insist on it.

AK Read more!

Wednesday, February 2, 2011

Thundersnow

ResearchBlogging.org


Yesterday's occurrence of thundersnow in Chicago had me looking for explanations. Wiki gave a lightweight summary, with just enough technical jargon to make it hard for a typical reader. Subsequent searching lead me to a bunch of good peer-reviewed data on the electrification of thunderstorms, but little of use understanding thundersnow.[3] [4] [5] [6]

I finally found a very recent survey by David M. Schultz and R. James Vavrek,[1] which while somewhat technical, gave me the insight I was looking for.

Summarizing everything: Thundersnow occurs when the conditions for thunderstorm-type convection are present at the same time as for general snow (in large amounts). This includes the presence of humid air above the freezing point while general temperatures, especially at the ground, are below freezing. A high lapse-rate is also necessary, in order to drive the rapid updraft which creates hail and/or graupel. Substantial electrification requires this.[3]

We don't yet know for sure how this electrification is caused,[1] [2] [3] [4] [5] [6] but the best guess involves collisions between growing graupel/hail particles and small ice particles.[1] [7]

Some Personal Observation:

My difficulty finding explanations is explained: we don't even know precisely what mechanisms lead to lightning even in thunderstorms, much less thundersnow (which has been much, much less studied). I had always assumed (and you know what that does) that electrification resulted from friction of ice particles with dry air, somehow I had never previously noticed the absence of this mechanism from those considered. Since both simulations and direct experimental measurements of this process would have been easy even in the 19th century, we can presumably rule this mechanism out.

None of the articles intended for general consumption (that I read) explicitly mentioned that we don't know the mechanism for electrification, which would have saved me considerable time trying to find it. (Although the descriptions of the theories and research were well worth the reading.) This points up a general defect in science reporting: the fact that the public is being kept pretty much in the dark regarding how much isn't really known for sure in science.

Schultz, D., & Vavrek, R. (2009). An overview of thundersnow Weather, 64 (10), 274-277 DOI: 10.1002/wea.376

Links:

1  An overview of thundersnow


2  A Climatology of Thundersnow Events over the Contiguous United States Open Access


3  Thunderstorm Electrification (Semi) Open Access


4  The 29 June 2000 Supercell Observed during STEPS. Part II: Lightning and Charge Structure Open Access


5  Relationships between Convective Storm Kinematics, Precipitation, and Lightning Open Access


6  The Electrical Structure of Thunderstorms(Semi) Open Access


7  The Ice Crystal–Graupel Collision Charging Mechanism of Thunderstorm Electrification Open Access Read more!