New "Jelly Pump" Rewrites Carbon Cycle

One of the fundamental aspects of Earth's ecological and climate systems is the way carbon moves through the biosphere. From land to air to water, through living organisms and even the plant's crust, carbon—the stuff of life—is always on the move. Scientists thought they had a pretty good understanding of how the carbon cycle works, until now. Recent work with strange, jellyfish like creatures called thaliaceans is causing scientists to re-evaluate the workings of the carbon cycle.

There are three orders of Thaliacea: Pyrosomida, Doliolida, and Salpida. An example of a thaliacean species is Thalia democratica, more commonly known as salps. Although salps appear similar to jellyfish because of the simple form of their bodies and their free-floating way of life, they are structurally most closely related to vertebrates, animals with true backbones. Salps are related to the pelagic tunicate groups, as well as to other bottom-living (benthic) tunicates.

Salps appear to have a form preliminary to vertebrates, and are used as a starting point in models of how vertebrates evolved. Scientists speculate that the tiny groups of nerves in salps are one of the first instances of a primitive nervous system, which eventually evolved into the more complex central nervous systems of vertebrates. Studies on salp brains have been done by Thurston Lacalli and Linda Holland and published in Philosophical Transactions of the Royal Society of London, but not much is known about what happens to animals with gelatinous bodies, whether thaliaceans or jellyfish, after they die.

It has been known for some time that salps and other thaliaceans assimilate CO2 and, when they die, take that carbon with them as they drift towards the bottom of the oceans. Most marine biologists thought that the dead salps simply became nutriment for other creatures. Then, in 2006, Mario Lebrato and Daniel Jones of the National Oceanography Centre in Southampton, England, made a surprising discovery off the cost of Côte d’Ivoire in Africa—a thaliacean graveyard.

According to a report in the Economist, the researchers were using a remotely operated deep-sea vehicle to study the sea floor near an oil pipeline when they happened upon the graveyard, but they immediately recognized the possible importance of their discovery. The existence of such large deposits of thaliacean corpses calls into question accepted thinking about one important aspect of climate change: how much carbon from the atmosphere ends up at the bottom of the sea? If thaliaceans are falling to the bottom of the sea in large numbers, they might be taking a lot of carbon with them.

As we explained in The Resilient Earth, there are two large pools of terrestrial carbon; geologic carbon stored in rock and fossil fuel deposits, and biologic carbon stored in living things or “in play” in the atmosphere and oceans. The source of both types of stored carbon is life. Over billions of years, uncountable billions of living things have collected carbon; growing, eating, breathing, reproducing and finally, dying. Most of this carbon came from Earth's primitive atmosphere in the form of carbon dioxide, which has steadily decreased over time.

Through a number of different biological and physical processes, carbon is circulated through Earth's biosphere and lithosphere. Vast amounts of carbon are now trapped in Earth's crust in the form of sedimentary rocks; limestone, dolomite, and chalk. This type of storage, or sink, accounts for the majority of carbon on Earth, 66,000,000 to 100,000,000 billion metric tons (gigatons or Gt).

SinkAmount in Billions of Metric Tons (Gt)
Atmosphere 578 (as of 1700) - 766 (as of 1999)
Ocean 38,000 to 40,000
Terrestrial Plants 540 to 610
Soil Organic Matter 1500 to 1600
Marine Sediments and Sedimentary Rocks 66,000,000 to 100,000,000
Fossil Fuel Deposits 4000
Amount of carbon stored in sinks. Source Dr. Michael Pidwirny

As seen in the table above, fossil fuel deposits, the other major type of geologic carbon, accounts for a paltry 4,000 Gt. The important difference between geologic and biologic carbon sinks is that geologic carbon is out of short term circulation. It is only released by slow processes, such as volcanism, degassing, and rock weathering, which can take millions of years. At least that was true before Man started digging up fossil fuels and burning them.

The other carbon sinks shown—the oceans, soil, atmosphere, and plants—all participate in what is called the carbon cycle of life, shown in the diagram below. This carbon is involved with life over the short term. It is the build-up of this carbon, in the form of CO2 in the atmosphere, that is responsible for the current global warming scare.

What is not clearly shown in the carbon cycle diagram are the geologic carbon sinks that store carbon for long periods of time. Carbon in these sinks take millions of years to cycle back into the biosphere. As mentioned, there is a tremendous amount of CO2 dissolved in the oceans. Though some of the CO2 in seawater remains as dissolved gas, a large portion is converted into other chemical compounds.

Among the compounds that are formed are carbonate (CO3) and bicarbonate (HCO3). Many forms of sea life (labeled Aquatic Biomass) have the ability to modify bicarbonate by adding calcium (Ca), producing calcium carbonate (CaCO3). Calcium carbonate is used by these organisms to build shells and other body parts. The illustration below shows how carbon cycles through the oceans and sedimentary rock deposits.

The ocean gets a disproportionate share of the carbon dioxide available to the ocean-atmosphere system. For every molecule of CO2 in the atmosphere there are about 50 CO2 molecules in the ocean. Why is this so? The main reason is that carbon dioxide readily reacts with water to make soluble ions, rather than simply diffusing gas molecules among the water molecules. There are a number of physical and biological mechanisms that “pump” CO2 about the ocean-atmosphere system. One is the physical pump: cold water holds more carbon dioxide in solution than warm water and because cold water is denser than warm water, this cold, carbon dioxide-rich water is pumped down by vertical mixing to lower depths.

Other reasons for the ocean’s big share of carbon are its “biological pumps.” The biological pumps, based on the life-cycles of various marine creatures, remove carbon dioxide from the surface water of the ocean, changing it into living matter and carrying it to the deeper water layers. When the ocean shares carbon dioxide with the atmosphere, it does so by not only simply taking on carbon dioxide into solution but also by incorporating the carbon dioxide into living organisms.

Carbon is constantly cycling between the atmosphere, the oceans, and living matter. Thaliaceans, jellyfish and other gelatinous animals roll in this process has largely been ignored by researchers because their bodies were thought to consist mostly of water with relatively little carbon content. However, as Lebrato and Jones report in Limnology and Oceanography, their analysis of thaliacean tissues revealed that the creatures were one-third carbon by weight—much more than expected. Jellyfish, by comparison, are 10% carbon, and single-celled algae around 20%. The high carbon content explains why thaliaceans are so dense and why they sink so quickly after they die. The key question regarding the dead thaliaceans is, when they get to the bottom does their carbon stay there? If so, thaliaceans may form a previously unsuspected CO2 pump—a “jelly pump.”

One way carbon stays on the seabed is in the form of calcium carbonate, the main ingredient of most animal shells. Uncountable numbers of tiny diatoms, raining down on the ocean floor over millions of years have created the vast deposits of chalk and limestone found within Earth's strata. But thaliaceans have no shells and no one is sure what a deep bed of dead salps turns into. Some thaliaceans do get buried before they have completely decomposed, and researchers have found evidence that dead jellyfish can also accumulate in trenches without much decomposition.

Why all this fuss about mostly transparent sea creatures that seem rather insubstantial? Because they gather around the world in feeding swarms, billions strong, feasting on algae—meaning the amount of carbon thaliaceans are potentially taking to the bottom of the sea is by no means trivial. According to Lebrato, it is difficult to make accurate estimations because the research is still in its infancy. But he estimates that the “jelly pump” sinks almost twice as much carbon as algae do.

Even if the carbon is not permanently buried, the lack of mixing between deep and shallow water layers in the ocean means that it is likely to stay out of circulation for quite some time. Of course, some of the recent revelations about the deep ocean return flows may change that conclusion. Either way, these are new factors that will have to be added to the GCM computer models used to predict future climate changes. Just like the thermohaline circulation, the carbon cycle we thought we knew so well has just changed in some fundamental ways. As a consequence, Earth's climate system has become even more complicated and environmental models previously concocted are shown to be wanting.

That is the way science works, new discoveries are made every day and what we thought we knew yesterday doesn't look so certain today. Every generation of scientists has its own long held, but erroneous theories to correct: Ptolemy's model of the solar system, fixed continents, any number of theories regarding the nature of matter, all have been accepted dogma and eventually discarded. New research is constantly changing the ideas that buttressed anthropogenic global warming, eroding its foundations like the tide excavates sand around a piling. How much longer before we move on to a more correct view of Earth's climate system? Look around, the change is happening right now.

Be safe, enjoy the interglacial and stay skeptical.

Really? It's not like we've got a ticket to ride...

Science is always going to discover more, and continually evolve itself. Nothing is proven, it's just failed to be rejected. Everybody thought the earth was flat, it was never proven, but they didn't reject the idea until we could come up with a better idea.

The "jelly pump" and MCP are just more ways we're finding that keep the ocean from becoming saturated with CO2. Once it becomes saturated, it wont hold any more. In some of the diagrams, we're seeing a net draw down of CO2 in the oceans and on land. The point that's really not driven home here is that anthropogenic sources, yes, that means people, are contributing more to the atmosphere than the ocean, terrestrial biosphere, or lithosphere are taking out.

A "paltry 4000" gigatons of fossil fuel reserves doesnt mean much when it's underground. Natural seeps and tectonics don't produce much, this is true. When we dig it up and crank it into the atmosphere it does matter. Where do you think it all came from? Ancient biomass, carbon that became locked up after something living used it to create cellular structure and energy. Labile carbon that was active in the cycle gets locked up and hidden away for eons, and now it's back.

The amount of CO2 in the atmosphere pales in comparison to that which lies in reserves, locked up in forms that are more or less inert. Whether it be at the bottom of the sea, or interred in a coal deposit, or even in solution in the ocean, it's stable. It's the change in sequestration that matters.

I won't say whether that waterworld is coming or that soylent green is around the corner because the ocean is dying, what I am saying is that we're pumping more CO2 into the atmosphere faster than any other natural source is taking it back out, so don't ignore that.

Nature will run its course, and homeostasis will balance most everything into relative stability, but we don't really need to be doing doughnuts on the lawn with an attitude of "oh yeah, it'll grow back".

"Gaia is a lot easier to say than a biological cybernetic system with homeostatic tendencies" James E. Lovelock

-Concerned Scientist

as for the dolt who thinks that refractory carbon at the bottom of the ocean is going to feed ocean plants-please don't have children.

"your comment"

Yes I agree with you mostly however in the last paragraph do you not think it was a bit too harsh?

You are going to ride anyway

The point of the article is that there are mechanisms—powerful mechanisms—in the Earth system that have yet to be discovered or incorporated into the warm-mongers' models. Is the planet warming? Yes, it has been for some time now. Do humans affect climate? Yes, as do termites, plankton and terrestrial plants. Is the end neigh? No. Man's emissions are just a temporary aberration that nature will take in stride. You are along for the ride whether you wish to be or not.

I had no idea that the Carbon

I had no idea that the Carbon cycle took so long.....the diagrams really helps me take this information in a lot better..:) and 100,000,000 billion metric tons of carbon is a lot to think about.

Grate article

Thank you very much for such a great article. I like to use the pictures in the school to educate my class. We are also reading you in germany in the nice village Kevelaer


this is a really interesting read. thank you
feel like i have just been sat back in a class room!

jen x

Forests and Trees

I have been saying for a long time to any who will listen that the fact that we have not had a runaway greenhouse in previous eras when CO2 levels and temperatures were higher argues that there exists dominant stabilizing negative feedback which necessarily prevents our recent contributions from having too great an impact.

I have been admonished repeatedly that we know all the feedbacks, and have been dutifully informed of them in ad ignorantium fashion. I have responded "keep looking", because when you discern the forest (the stability of the global climate system to date) from the trees (the known feedback mechanisms), you must conclude that our models are inadequate.

This is the fundamental question regarding the AGW hypothesis. In order to forecast dire consequences, the models have to assume that positive feedback is dominant. But that is impossible, because positive feedback does not need a deterministric trigger to assert and sustain itself, nor does it retreat in the absence or diminishment of external drivers.

Earth's Experiments

Prezakly! We need to acknowledge:

The postulate of positive feedback in the system (i.e., that water vapor multiplies the effect of CO2, which raises air and ocean temperatures driving even more CO2 and H2O into the atmosphere, and so on) has been disproven soundly in thorough experimentation ... by Planet Earth. The geological record shows that every combination of low and high CO2 (slightly lower than present up to 20X current numbers) and high and low temperature (from tropical poles to ice sheets nearly to the equator) has been tried, at great length, and no "runaway" has occurred. The minute range of values we're now experiencing and playing with thus has no more chance of causing runaway than spitting in the ocean has of causing a tsunami.

Something New Everyday

One of the main points we tried to illustrate in The Resilient Earth is how fundamentally incomplete our knowledge of Earth's climate system is. Over the past several months I have been posting articles based on newly published journal articles, each reporting the discovery of some previously unknown facet of our environment. One of the reasons I chose to become a scientist was the opportunity to discover something new everyday.

Those who have told you we know all the feedbacks, all the factors, are only fooling themselves. Sadly, the current example is not without ample historical precedent: "we know everything" is the motto of fools, in the past, in the present and in the future.


CO2 is a fertilizer for land based plants. Could it do the same for ocean plants?

CO2 is part of the process to build shells. Does that mean that more ocean CO2 creates bigger/thicker shells?

.... more ocean CO2 creates bigger/thicker shells?

Or more faster growing shellfish?
Less expensive steamed clams and lobster sauteed in garlic butter!

More Lobster?

I think I am gong to try infussing more carbon into my fish tank and see what happens over time with the shell fish. I have several tanks in the home and i am willing do take two of them and try this little experiment out. Will update with results (give me a few months to see how it turns out).

Your 'speriment

OK, it's been about 7 months. How did it go? Report! Immediately!!