Of Silicon, Iron, and Volcanoes

I was watching a bunch of hard core “Pro-AGW” folks spout the standard propaganda lines at the “64th World Affairs Conference” in the global warming segment. All from the Very Watermelon Green POV, near as I could tell. It was all gloom and doom and end of the world is neigh (unless, of course, we hand a bunch of money to green NGOs, the UN, and them…) and it is all due to Evil Humans.

Not a skeptic in sight.

Even in the audience. (It was taking place in Colorado, on a college campus IIRC). Most of the questions very neatly fit the “narrative” and worked as a progression. I suspect some may have been planned in advance. Being good leftists, you can order a copy of the event video for a nice cash payment… no free online youtube for these folks: http://www.ncrsusa.com/cgi-bin/store/main-cwa.html

Most of it was the same-old-same-old; but one bit caught my attention. There was a Grave Concern about how the very foundation of life on earth, our OXYGEN, was at risk. Why? Turns out that the opacity of the ocean has been reducing. This is interpreted as a reduction in plankton (thus a reduction in oxygen production in the oceans) due, of course, to CO2 “pollution”. We must act now to save the planet or we will all suffocate as the oceans DIE!!! (as most all life in the ocean has a food chain leading back to plankton, it’s an easy scare argument to make).

Now, the number of problems with this argument are so numerous as to be problematic just deciding where to start. How about the fact that plankton is a mix of animal and plant forms? For the oxygen level to be dropping, the plant parts need to die while the animal parts thrive. More CO2 is NOT going to kill off the plants, they will grow faster and thrive. Ooops… Or how about the the fact that we’ve been hauling fish out of the ocean at an astounding rate, largely with nets that let the littlest ones escape. Shift the entire size spectrum away from large carnivores and toward much smaller fish, think maybe you left more plankton eaters alive and removed their predators? (Or the corollary that there’s been a rise in jellyfish as we removed their predators – sea turtles – and jellies eat a lot of plankton.) No, no choice other than ‘CO2 did it and it’s our fault!!!’

So I decided to look into that particular claim just a little bit. An example of the Green Panic can be seen here:


In the long term, you might be right. The complete collapse of our ocean fisheries could starve a terrifying percentage of the world.

That was voted the “best answer” on that site when I read it…

Right behind it was:

..:: “Every day, 70 MILLION TONS of CO2 are released into Earth’s atmosphere. ( remaining in the atmosphere for thousands of years )

..:: “Every day, 20 MILLION TONS of that CO2 are absorbed into the OCEANS, thereby increasing the overall ACIDITY of the OCEANS.

By 2100, Ocean acidity will increase another 150 to 200 hundred percent.

This is a dramatic change in the acidity of the oceans. And it has a serious impact on our ocean ecosystems; in particular, it has an impact on any species of calcifying organism that produces a calcium carbonate SHELL.


..:: “These are changes that are occurring far too fast for the oceans to correct naturally, said Dr Richard Feely with the US National Oceanic and Atmospheric Administration (NOAA)

..:: “Fifty-five million years ago when we had an event like this (and that took over 10,000 years to occur), it took the oceans over 125,000 years to recover, just to get the chemistry back to normal,” he told BBC News.

..:: “It took two to 10 million years for the organisms to re-evolve, to get back into a normal situation.

..:: “So what we do over the next 100 years will have implications for ocean ecosystems from tens of thousands to millions of years. That’s the implication of what we’re doing to the oceans right now.”



it’s now or never…
By: Eco Citizen

Yet we know that it isn’t CO2 that controls diatoms, but silicon:


Diatoms, Silicon and Carbon

From this article:


we have in the opening paragraph:

Diatoms are the world’s largest contributors to biosilicification and are one of the predominant contributors to global carbon fixation. Silicon is a major limiting nutrient for diatom growth and hence is a controlling factor in primary productivity. Because our understanding of cellular metabolism of silicon is limited, we are not fully knowledgeable about intracellular factors that may affect diatom productivity in the oceans.


Here we are smack up against all that “settled science” again. Predominant carbon fixer. Don’t know what controls its productivity. Understanding is limited. Silicon is limiting (and I wonder just how much work has been done on the “silicon cycle” to see how it controls the carbon cycle via diatoms… a google of ‘life “silicon cycle”‘ gave about 5700 articles and a lot of them are ‘misses’ where the terms are there but the topic is different. I think the diatom and silicate guys are missing out on the AGW Gravy Train here. Someone needs to send them the memo… ).

How important? Per the wiki “They are especially important in oceans, where they are estimated to contribute up to 45% of the total oceanic primary production.” So about half of what’s being made in the ocean. I’d say that matters. But wait, there’s more…

There is a battle between differing ocean critters over who gets to control the ‘silicon cycle’. This is thought to be related to the evolution of grasses (that also use silicon and, I presume, provide a more bio-available form of it in runoff to the oceans, but that’s just a guess). So given all that we’ve done to change the pattern of grasses on land and what lives in the oceans (think of all the various filter feeders AND things that prey on them which we’ve hauled out of the ocean and eaten to the point where they are at very low levels); do you think that could be doing something to the pattern of life in the ‘silicon cycle’ that could then impact carbon recycle? And what happens when Nature has a hissy fit and a load of volcanoes unload. They dump silicate ash in the oceans too… and have a big impact on things like sunlight.

What we don’t know here is huge.

From: http://en.wikipedia.org/wiki/Diatom

Although the diatoms may have existed since the Triassic, the timing of their ascendancy and “take-over” of the silicon cycle is more recent. Prior to the Phanerozoic (before 544 Ma), it is believed that microbial or inorganic processes weakly regulated the ocean’s silicon cycle. Subsequently, the cycle appears dominated (and more strongly regulated) by the radiolarians and siliceous sponges, the former as zooplankton, the latter as sedentary filter feeders primarily on the continental shelves. Within the last 100 My, it is thought that the silicon cycle has come under even tighter control, and that this derives from the ecological ascendancy of the diatoms.

However, the precise timing of the “take-over” is unclear, and different authors have conflicting interpretations of the fossil record. Some evidence, such as the displacement of siliceous sponges from the shelves, suggests that this takeover began in the Cretaceous (146 Ma to 65 Ma), while evidence from radiolarians suggests “take-over” did not begin until the Cenozoic (65 Ma to present). The expansion of grassland biomes and the evolutionary radiation of grasses during the Miocene is believed to have increased the flux of soluble silicon to the oceans, and it has been argued that this has promoted the diatoms during the Cenozoic era. However, work on the variation of diatom diversity during the Cenozoic suggests instead that diatom success is decoupled from the evolution of grasses, and that diatoms were most diverse prior to the diversification of grasses. Nevertheless, regardless of the details of the “take-over” timing, it is clear that this most recent revolution has installed much tighter biological control over the biogeochemical cycle of silicon.

Ok, and we get to find out what “siliceous sponges” have been doing lately too if we want to understand the actual controls in the “carbon cycle” (via the silicon cycle controlling the diatoms as major primary production…)

So if we have, oh, I don’t know, maybe removed a lot of predators on “siliceous sponges” via fishing they might be getting a larger share of the rate limiting nutrient silicon?

The blame was only laid at the feet of “Ocean Acidification” even though the ocean was, and continues to be, an alkaline pH. Just nutty. Oh, and remember that shell fish and similar life is quite happy to live in truly acid waters, at pH up to the 4.x range. We have many “existence proofs” of it:


So is there anything “real” in the idea that the diatoms and plankton are diminishing?


Rising sea temperatures can harm the tiny plant life that forms the base of the oceans’ food chain as well as affect the diversity of marine life, two new studies have found.

Over the years, humans have affected the oceans by pollution and over-fishing and through habitat alteration caused by dredging and other activities. Less understood is the role of higher sea temperatures, which many scientists believe is linked to global climate change. Scientists estimate that the oceans have warmed a total of roughly half a degree Celsius on average over the past 100 years.

Researchers have long debated whether phytoplankton concentrations have increased or declined
. The algae have flourished in many coastal areas because increased runoff from rivers brings nutrients that the algae gorge on. However, no one has properly assessed whether the global oceans are losing or gaining phytoplankton, which forms the base of the marine food chain, from crustaceans to fish and ultimately to humans.

Consistent satellite-based measurements exist only from 1997,
so scientists at Dalhousie University in Nova Scotia, Canada instead used data obtained with a simple oceanography device known as a Secchi. Used by scientists since the late 1800s, a Secchi is a disk lowered into the water to provide an estimate of water clarity and thus serves as a proxy measure of phytoplankton abundance.

By collating and analyzing about half a million Secchi observations, plus other direct measurements of algae, the Dalhousie team estimated that phytoplankton levels declined by about 1% of the global average each year from 1899 onward. The data are more reliable for recent decades, translating into a 40% decline in algae since 1950.

The team investigated several factors that could have caused the decline, including wind intensity, cyclical climate changes and sea-surface temperature. “We found that temperature had the best power to explain the changes,” said Boris Worm, a marine biologist at Dalhousie and co-author of the study.

Marine algae live in the upper layers of the ocean but rely on nutrients that circulate up from lower layers. Rising temperatures mean the different water layers mix less with each other, so fewer nutrients reach the algae. However, Dr. Worm notes that algal abundance can be affected by other factors, such as shifts in predator-prey populations.

In other words it is a whole lot of speculation wrapped around a change observed in turbidity. That based on a spliced record of questionable quality based on folks sticking a disk in the water (under various lighting conditions) and recording where they thought it became hard to see. Oh, and turbidity varies a lot by location, so exactly WHERE those readings where taking matters.

Think maybe removing the grasses from vast areas of the globe and running them through cows, goats, and pigs might reduce the silicon flow into the ocean? Think maybe turbidity might be related to OTHER things than diatoms? How about the simple fact that we were rising out of the bottom of the Little Ice Age starting about 1850, so that ‘start of data’ in 1899 is just catching the warming of the oceans from that NATURAL process? The reduction in turbidity was well underway long before CO2 levels were raised significantly. I think that matters.

We’ve dammed many rivers globally. In those rivers, sediments are captured. That’s silicon that is not making it to the ocean. Iron too. We have a historical record of a lot of volcanoes in the Little Ice Age, and lower levels of volcanoes now. (Heck, I wanted to see the one in Hawaii and it was inactive for most of the couple of decades when I was visiting. Only recently has it gone back to dumping lava into the ocean.)


About sixty percent of the world’s marine production occurs in just two percent of its surface water (Schueller 1999). the equatorial Pacific and the Southern Ocean, do seem to have the necessary amounts of nutrients for production at the surface yet are still relatively unproductive.

These waters are consistently rich in nitrogen and phosphorous (in the form of NO3 and PO4) and exhibit no seasonal variation in abundance.

These are called High-Nutrient, Low-Chlorophyll (HNLC) waters and they make up about 20% of the worlds oceans.
It was later found that phytoplankton growth in major nutrient-rich waters is limited by iron deficiency.

Volcanoes spit out a large quantity of iron:


Intermediate lava

Intermediate or andesitic lavas are lower in aluminium and silica, and usually somewhat richer in magnesium and iron. Intermediate lavas form andesite domes and block lavas, and may occur on steep composite volcanoes, such as in the Andes.
Mafic lava

Mafic or basaltic lavas are typified by their high ferromagnesian content
, and generally erupt at temperatures in excess of 950 °C. Basaltic magma is high in iron and magnesium, and has relatively lower aluminium and silica, which taken together reduces the degree of polymerization within the melt. Owing to the higher temperatures, viscosities can be relatively low, although still thousands of times more viscous than water. The low degree of polymerization and high temperature favors chemical diffusion, so it is common to see large, well-formed phenocrysts within mafic lavas. Basalt lavas tend to produce low-profile shield volcanoes or “flood basalt fields”, because the fluidal lava flows for long distances from the vent. The thickness of a basalt lava, particularly on a low slope, may be much greater than the thickness of the moving lava flow at any one time, because basalt lavas may “inflate” by supply of lava beneath a solidified crust. Most basalt lavas are of ʻAʻā or pāhoehoe types, rather than block lavas. Underwater they can form “pillow lavas”, which are rather similar to entrail-type pahoehoe lavas on land.

That pahoehoe reference matters as that is one of the common types on the Hawaiian Islands. You know, where there wasn’t any volcanic action to speak of for a few decades…

Volcanic and Temperature Cycles

Volcanic and Temperature Cycles

Sure looks to me like the volcanic activity cycles with the temperature cycles (though perhaps with a small time offset).

In Conclusion

We have a known dependency of phytoplankton and diatoms on iron and on silicon. We know that increased CO2 helps plants grow, it does not reduce their growth. The only logical conclusion is that the rate limiting nutrients iron and silicon are responsible for any limited growth of phytoplankton and diatoms. More CO2 will result in more growth, not less. (Which, BTW, would then deplete the iron and silicon and rate limit on them).

It is slightly speculative that volcanic activity cycles with the temperature cycles, but a casual observation of the historical narrative sure looks like it does. There is also a plausible mechanism in the tidal cycles of the moon:


Which, in addition to the direct effects on ocean turnover and current could also cause changes in tidal forces in the land and magma under it, and thus volcanic activity.

During the LIA the stories from the exploration of the Pacific had far more reports of volcanic islands.


Major eruptions are relatively rare events and seem to occur in clusters as the chart (stratospheric aerosol as measured by NASA GISS Aerosol Optical Thickness) below shows. The late 1800s to the early 1900s was a very active period with Krakatoa (Indonesia between Java and Sumatra in 1883) as the major event. With a quiet sun, it is no surprise this era was very cold. A quiet sun is associated with lower solar irradiance (energy emission) and less heat input into our atmosphere.

The 1920s to the 1940s was a period of very little volcanic activity that coincided with a rapid increase in solar irradiance and multi-decadal warming in both oceans with a resulting warming of global temperatures. The sun and oceans are believed to be the primary drivers but lack of volcanic ash may have augmented the warming.

Indonesia, in particular, had a couple of spectacular explosions, including the one that lead to “1800 and froze to death” or “the year without a summer”. Dumping immense quantities of ash into the ocean will fertilize it with both iron and silicon, causing a ‘bloom’ of diatoms and phytoplankton. It ought to come as no surprise that when that fertilization reduces, the growth of those organisms also reduces.

Furthermore, we have no idea at all what our intense fishing has done to the ecology of the oceans. To what extent has our dramatic shifting of the predator / prey relationship increased the plankton eaters and reduced their predators? To what extent have we removed predation from siliceous sponges?

In the end, it is much more about iron, silicon, volcanoes and fish populations than CO2.

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About E.M.Smith

A technical managerial sort interested in things from Stonehenge to computer science. My present "hot buttons' are the mythology of Climate Change and ancient metrology; but things change...
This entry was posted in AGW Science and Background, Earth Sciences and tagged , , , , , . Bookmark the permalink.

12 Responses to Of Silicon, Iron, and Volcanoes

  1. p.g.sharrow says:

    This AGW science is too complex for me. Every place in the world that I have been the clearest waters were the least productive. pg

  2. Tim Clark says:

    That event was held at the U of Colorado. Not to be confused with Colorado State University, where I received my 1st degree. True story- a bunch of us red-neck cowboys would go to boulder on week-ends to pick up loose hippie chicks and start fights with scholarly eco-fascists. Ahh, the good days. But I’m much better now.

  3. Panther77 says:

    This must be how Jupiter controls the planet? http://english.pravda.ru/science/earth/15-06-2011/118207-volcanoes-0/

  4. ganavion says:

    I read somewhere that the quantity of CO2 contained in the oceans is much more of that contained in atmosphere (60 times ?).
    If this is true, how can a portion of a very little quantity greatly influence a much bigger quantity ?

    [ Reply: Look at the chart at the top of https://chiefio.wordpress.com/2009/02/25/the-trouble-with-c12-c13-ratios/ from the wiki and you will find air at 750 units, deep ocean at 38,100 units (so much larger ocean content). So I share your wonder. -E.M.Smith ]

  5. Pascvaks says:

    I’m sure you’ve all noticed the chart, and that each cool down has been deeper than the last. Now if you were a former VP who happened to be as sharp as a tack, or one of a few rather cunning university Prof’s who thought he/they were also as bright as a certain VP, and you wanted to make a real killing in the market, would you be screaming and shouting to the world that we were all going to freeze to death in the coming century, and start a panic and stampede away from current locations to warmer climes? Or would you, perhaps in a rather slippery fashion, take the exact opposite approach, and tell the world that something like CO2 (a little gas everyone is very familiar with) is going to cook the planet and then, of course, get in bed with Canadian Billionaires selling beach front permafrost property on the Arctic Shore Line, telling everyone the permafrost is melting, and buying dirt cheap tropical rain forest sections as fast as you possibly could? I ask you, what would you do, really? Anybody want in on some of the action? (SarcOff)

  6. adolfogiurfa says:

    Well, let us turn some green dogmas up side down:
    – A tree trunk is made out of Wood=Cellulose
    – Cellulose is a polymer of glucose.
    – Glucose (C6H12O6) is made out from CO2 and Water, through photosynthesis.
    – A tree trunk, then, is made out from CO2
    – A tree trunk, say, weighs at least one metric ton (1,000 kgs, 2204 pounds)
    – Paper is made out from tree trunks´s cellulose.
    – A tree trunk has 40% Carbon, 400 kgs. “C”
    – Paper factories replace trees to be able to keep on business.
    – Then, if we DO NOT RECYCLE paper we will be SAVING THE WORLD!
    …In any case, recycling is anti-economical: every time we recycle we shrink the market and somebody loses its job.

  7. E.M.Smith says:

    @P.G. Sharrow:

    Yup. Life loves a good roll in the mud…

    @Tim Clark:

    Colorado always fascinates me. Mix of new hippies and old cowboy culture. Nice mining and explosives school too ;-)


    There’s some kind of volcano link, IMHO, but exactly how is a bit murky.


    Interesting point. A “wag the dog” doesn’t work. Air CO2 is 0.0197 of ocean CO2. Not much leverage there ;-)


    That’s the critical context that keeps being ignored. Not only is each low lower, but each high is lower, narrower, and shorter. Gets even worse in the very long term:


    And even just looking at the Holocene, we’re on a several thousand year ‘wobble downward’:

    where the only reason the very recent ‘spike’ up looks different is because we have enough resolution to see it (the more distant past is averaged out into a slower curve that takes out the fast spikes each way).

    Basically, we rolled over the top of the interglacial about 7,000 year ago (when the Sahara was green from the warmth induced added rain) and had a cold inflection (that lead to the climate catastrophe of a drying Sahara and the rise of Ancient Egypt as folks ran to the river) about 4,000 BC / 6,000 BP. (the ‘dip’ over the 6 on the Holocene chart). We’re headed into the freezer. The only real good thing is the fact that it takes so long no one notices in any single lifespan.


    Yup. Clearly the answer is to start sending everyone a phone book for the whole country each year, then bury them in a dry landfill when the new ones come out ;-)


  8. adolfogiurfa says:

    @E.M. …though I think that trees and plant also take carbon from the soil, that explains the big consumption of urea (CO(NH)2: carbon di-amide), humid acid, etc., because otherwise we could not explain the big volume and weight of trees only by the scarce, demonized and humble CO2.
    BTW: Don´t you think the earth has an “open economy” of gases?, what about that VENUS TAIL which will be brushing the US from Florida to California next June 5th?

  9. adolfogiurfa says:

    @E.M.: In June, 1996, Venus passed through a very close inferior conjunction with the Sun. At that time the CTOF detector of the CELIAS mass spectrometer experiment on the SOHO spacecraft near Earth’s L1 Lagrangian point was measuring heavy ions in the solar wind ∼4.5 × 107 km downstream of Venus. Close to the time predicted by simple geometric arguments for passage of SOHO through the Venus wake, CTOF made three encounters with unusual fluxes of O+ and C+ ions. Their energy distributions resembled those of tail rays originating in the Venus ionosphere or ionopause region rather than of ions produced in the corona of neutral atoms that surrounds the planet. The C+ abundance was ≈ 10% of O+. The observed O+ speed was very close to the simultaneous solar wind speed and the O+ temperature was a cool 5600 K/amu. The flux densities for the three events were (2.4–4.4) × 10³ cm−2s−1.

  10. larrygeiger says:

    Re: adolfogiurfa says –

    Trees are made of air. Isn’t that cool. The air that we breathe (C02 and all) can be made into a 200ft tall tree! That’s right, basically just air :-)

    I had a little discussion with a recalcitrant park range one day. He was all freaked out about people picking up dead sticks and wood from the ground a burning it in their fire rings. The natural order of things and what not. I explained to him that what they were burning was air. Just returning it to the atmosphere. All of the minerals and good stuff in a tree are really mostly all in the leaves. Boy did that ever send him ballistic! Great fun.

  11. E.M.Smith says:


    Yeah… on a recent visit to The Pinnacles National Park I saw a sign. It said, roughly “No Vegetation to be touched for any reason”. No collecting, burning, whatever. It seems to be the new big thing that every single scrap of plant material be ‘left be’. It would seem that slow oxidation via rot is preferred to fast oxidation via making coffee ;-) Though “why” escapes me… Since darned near nobody will walk more than 1/10 mile into the woods from the campground (unless on a hike on a marked trail when they will not be cooking…) the potential “damage” from someone burning a piece of dead wood in a bbq pit is pretty minimal. But no. You get to bring your own firewood and add an excess of potash to the local ecology ;-)

    It also means that the informal propagation of some at risk species is thwarted. In California we have an odd walnut tree. It is fairly rare. Why? It’s not as productive in giant tree farms as the English or Black walnut, so little commercial interest. Some are used for rootstock for English Walnuts as they are well adapted to our dry soils. So if I’m out there and see a couple of these nuts, and want to plant them, nurture them, and create a tree or two making thousands of more nuts, I can’t. They are to be left to be eaten, get crushed in being stepped on, or whatever.


    But it looks like I can get some if I hang out in Palo Alto at the right time of year and don’t look too suspicious…

    The presumption is that all “regular folks” are only going to be destructive; none could possibly be intelligent and motivated to good ends…

    So the amateur botanist is to be forbidden. And definitely forget the idea of taking a science class to the field and showing them how to make a bug or leaf collection…

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