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Lowering Carbon with Algae

Spawning algal blooms by fertilizing the Southern Ocean with iron could help sink atmospheric carbon to the deep ocean—and maybe slow the course of climate change.

By | July 18, 2012

image: Lowering Carbon with Algae An algal bloom in the Arabian Sea NASA

Great blooms of oceanic algae, called phytoplankton, take carbon out of the atmosphere during photosynthesis, much of which is then taken deep into ocean with them when they die. Scientists have theorized that this mechanism helped cool the earth during historic ice ages by removing carbon dioxide from the atmosphere and storing it at the ocean floor, where it cannot be recycled back into the atmosphere. Inducing algal blooms on a large scale could do the same today, reducing the impact of carbon dioxide on the greenhouse effect and slowing the impact of global climate change.

Indeed, as reported today (July 18) in Nature, scientists have seeded the ocean with iron and watched as the resulting bloom flourished, then died, sinking down to the deep ocean with a significant amount of carbon in tow.

"[The authors] were focused and quite successful at seeing if you added iron, what would be the biological response of the phytoplankton? What was the fate of the carbon and nutrients they sucked up?" said marine geochemist Ken Buesseler of the Woods Hole Oceanographic Institution, who was not involved in the study. "This is probably the best example of a group that stayed out long enough and looked deep enough to see if there were any effects below the surface."

During glacial periods, more dust rich in iron, an essential nutrient for algae, reaches the oceans. Iron is particularly limiting in the Southern Ocean, and previous studies have shown that adding iron to the surface waters does induce large blooms of algae. In 2004, Victor Smetacek of the Alfred Wegener Institute for Polar and Marine Research, Germany, and his colleagues decided to repeat these experiments and closely monitor what happened. They seeded a portion of the Southern Ocean and followed the progress of the resultant algal bloom for 37 days. The team took regular profiles of the nutrients and biomass down through a column of water to the sea floor, several thousand meters deep. From their data, they were able to see good correlation between what the algae were using up at the surface, and what was showing up again in the deep, as the phytoplankton died and sank.

The team chose to spread the iron over an eddy, an isolated spinning column of water, so they could minimize the exchange of water and nutrients with the open ocean, effectively using the eddy as a natural beaker. They were able to estimate that about half of the bloom biomass sank to depths of 1,000 meters or more, well below the upper mixed layer (the first 100 meters or so in this region) that allows open exchange with the atmosphere. Carbon sunk in this way can stay stored for centuries, until deep, slow ocean currents eventually bring it back to the surface.

Smetacek says that while longer experiments are still needed, as are samples from the sea floor sediment itself, rather than just deep water, to confirm what settles into the mud, preliminary estimations suggest that as much as one gigaton of carbon could be removed from the atmosphere in this way each year—a quarter of the carbon that is currently accumulating in the atmosphere as a result of human activities on an annual basis. Thus, iron fertilization could serve as an effective geoengineering strategy to help slow the harmful effects, such as climate change, that come with rising atmospheric carbon. However, both Smetacek and Buesseler warn of the potential drawbacks of large-scale fertilization.

"If you do this for a longer time scale, you could change the structure of the ecosystem,” said Smetacek. By increasing the phytoplankton population, the number of microscopic animals that feed on it could also explode, rapidly using up all the nutrients at the surface and creating "dead zones" where nothing can thrive, he explained. In addition, some algal blooms release harmful gases and toxins which could damage surrounding marine ecosystems.  No such consequences occurred in the present experiment, Smetacek said, but drawbacks of larger experiments "should be monitored by an independent group of scientists that are working in a non-profit manner."

The ocean's ability to sink carbon also depends on the many changes we are already making to the marine environment, including rising ocean temperatures and the decline of whale and krill populations in the Southern Ocean, which have previously played a large part in the cycling of nutrients harnessed by algal blooms. This experiment and its predecessors play important roles in understanding how the ocean, which naturally sinks about a third of our carbon emissions, plays in the global carbon cycle.

"The experiments themselves are not  of huge environmental consequence, [but] we can learn a lot from them," said Buesseler. "This was a successful way to study the ocean and climate."

V. Semtacek et al., "Deep carbon export from a Southern Ocean iron-fertilized diatom bloom," Nature, 487: 313–319, 2012.

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Avatar of: 1969_73

1969_73

Posts: 3

July 19, 2012

I previously suggested to NASA that they send a test sample of magnetic particles into the atmosphere to see if they could deflect the sun, and localize over the poles to delay icecap melting. I got no response, but to me, this idea was better than the Freakonomics authors' suggestion of sulfur dioxide, which would acidify the oceans.
This new report indicates that if iron particles fell into the ocean, there would be an added benefit of stimulating algal conversion of CO2. One question is how much energy would be needed to produce the iron?

Avatar of: Severn72

Severn72

Posts: 2

July 19, 2012

Isn't this the same process, algae blooms that sink to the bottom, that causes dead zones?

Avatar of: AlanBradbury

AlanBradbury

Posts: 7

July 19, 2012

This is self evident and I didn't see anything - at least in the article - that added to existing evidence or knowledge. The reality is that we have HUGE evidence all around us, in enornous abundance, that nature has sequestered CO2 via algea blooms over many millions of years - the evidence is COAL, OIL and GAS. Since abiotic mechanisms are widely discounted these deposits have only one source - uptake via photosynthesis. Now, the factor that has been ignored is that of dead zones - incredibly, the authors above suggest dead zone 'might' happen as a result of large scale ocean photosynthetic stimulation via iron. This is an incredible statement,  since a) the deep or middle ocean areas ARE dead zones in the sense of hardly any biomass supported due to lack of minerals to support biomass, and secondly, we rarely find dead zones in well mineralised areas (such as upwellings in polar regions) but instead find ocean biomass and diversity blooms. Its simply and self evidently a case of emulating the same mineral densities, so there is no need whatsoever to 'prove' that fertilisation can be done in a way that is beneficial to ocean food chains and ecology. It happens already throughout interstital and shoreline environments, the continental shelf and the polar regions. Now, in the deep or mid oceans, the advantage is that at greater depth different chemistry can be manifested at depth via the fall of sediment (carbohydrate and other hydrocarbons) to the ocean depth from the stimulated photosynthetic layer, including phytoplanktonic and marine fecal deposits. The only way to store this carbon permanently is to overwhelm the ocean depths with hydrocarbon sources so that they cannot be oxidised back into CO2 and H20, ie by using up local O2 at the sediment layer, helped by the sealing effect of new sediment accumulating above. This causes hydrocarbons to be degraded slowly yielding H2O and a bit of methane - which is 'hydrostatically' locked into position at depth, and carbon rich deposits, locking away carbon. This *requires* a "dead zone" otherwise you re-oxidise the carbon back to CO2. For ocean sequestration to work you manifestly, self evidently REQUIRE low oxygen. One condition that might have helped that in the past, asside from rate of sedimentation, was H2S - hydrogen sulfide causes O2 breathing oxygenic life (animals like worms) to shut down metabolism so that H2C (hydrocarbons) accumulate at depth or in shallow waters. If you 'dump' a lot of hydrocarbons (biomass) in deep water, you will overwhelm local oxygen supply in deep circulating waters. Historical increases in H2S are caused not just by geological (hydrothermal) release of H2S but also by other factors like availability or consumption at depth (or in sediment) of O2, if O2 is available, a number of animal life forms, that break up the sediment layer and allow O2 containing waters into it, cannot cope with H2S. They can only cope with H2S when they can 'oxidise' it with dissolved O2.  Too much sediment, and that can be overwhelmed. Its not a bad thing, this is a key part of how CO2 was taken out of the atmosphere throughout the geological record and is vital for the planet - and hydrocarbon deposition. This is what we want at depth by increasing surface biomass and its 'fallout'. Ocean circulation changes also will impact on these processes. Previous research showed that ocean algea blooms resulted in increased marine 'snow' falling to the ocean floor but it being reoxidised by deep and mid water life. This was actually - althought they failed to realise it - a result of short term, local effects. If there is large areas seeded with additional growth, you get de-oxygenation of deep waters circulating at the boundary between seafloor and ocean - which yields permanent removal (not reoxidised) carbon, yielding hydrocarbon deposition. There is no need to prove that this happens, its an extension of first principles and seen in the enormity of the  geological record!!  It is not dangerous either, as the supposedly vulnerable and delicate marine ecosystems are actually the oldest - therefore they HAVE to be very robust. Increasing surface photosynthesis in the mid ocean will have little effect on these ecosystems near to shore, and in fact may help them by taking out poisonous elements in the water. Now, the big issue with ocean fertilisation is SURFACE HEATING  and stratification. This actually COOLS the ocean reducing sea level rises - I predicted this, again from common-sense first-principles, and last year a physicist proved the idea using a computer simulation for the first time. Surface photosynthesis simply obviously causes the surface water to heat up due to increased solar absorbtion per cm of depth, which automatically raises the rate of evaporation and heat loss back out from the ocean (the external losses). This will cause, unless intelligently and topographically stimulated, increased hurricanes and rain fall, but this can be used for good as well as bad. I have to say I find it EMBARRASSING that I understand the system far better and effectively than paid ocean 'researchers' and can tell them what to do, when I am sitting at home using basic science and physics principles. Its proof you DONT need a degree, a great deal of maths or a doctorate or funding to make scientific progress, and it is proof we are getting bad value for money from those privilidged to spend their lives researching. I have gone beyond them IN MY SPARE TIME. I think it is time I got a grant, and I know where savings can be made in the current grant allocation.

Avatar of: AlanBradbury

AlanBradbury

Posts: 7

July 19, 2012

 

This is self evident and I didn't see anything - at least in
the article - that added to existing evidence or knowledge. The reality is that
we have HUGE evidence all around us, in enornous abundance, that nature has
sequestered CO2 via algea blooms over many millions of years - the evidence is
COAL, OIL and GAS. Since abiotic mechanisms are widely discounted these
deposits have only one source - uptake via photosynthesis. Now, the factor that
has been ignored is that of dead zones - incredibly, the authors above suggest
dead zone 'might' happen as a result of large scale ocean photosynthetic
stimulation via iron. This is an incredible statement,  since a) the deep
or middle ocean areas ARE dead zones in the sense of hardly any biomass
supported due to lack of minerals to support biomass, and secondly, we rarely
find dead zones in well mineralised areas (such as upwellings in polar regions)
but instead find ocean biomass and diversity blooms. Its simply and self
evidently a case of emulating the same mineral densities, so there is no need
whatsoever to 'prove' that fertilisation can be done in a way that is
beneficial to ocean food chains and ecology. It happens already throughout
interstital and shoreline environments, the continental shelf and the polar regions.
Now, in the deep or mid oceans, the advantage is that at greater depth
different chemistry can be manifested at depth via the fall of sediment
(carbohydrate and other hydrocarbons) to the ocean depth from the stimulated
photosynthetic layer, including phytoplanktonic and marine fecal deposits. The
only way to store this carbon permanently is to overwhelm the ocean depths with
hydrocarbon sources so that they cannot be oxidised back into CO2 and H20, ie
by using up local O2 at the sediment layer, helped by the sealing effect of new
sediment accumulating above. This causes hydrocarbons to be degraded slowly
yielding H2O and a bit of methane - which is 'hydrostatically' locked into
position at depth, and carbon rich deposits, locking away carbon. This *requires*
a "dead zone" otherwise you re-oxidise the carbon back to CO2. For
ocean sequestration to work you manifestly, self evidently REQUIRE low oxygen.
One condition that might have helped that in the past, asside from rate of
sedimentation, was H2S - hydrogen sulfide causes O2 breathing oxygenic life
(animals like worms) to shut down metabolism so that H2C (hydrocarbons)
accumulate at depth or in shallow waters. If you 'dump' a lot of hydrocarbons
(biomass) in deep water, you will overwhelm local oxygen supply in deep
circulating waters. Historical increases in H2S are caused not just by
geological (hydrothermal) release of H2S but also by other factors like
availability or consumption at depth (or in sediment) of O2, if O2 is
available, a number of animal life forms, that break up the sediment layer and
allow O2 containing waters into it, cannot cope with H2S. They can only cope
with H2S when they can 'oxidise' it with dissolved O2.  Too much sediment,
and that can be overwhelmed. Its not a bad thing, this is a key part of how CO2
was taken out of the atmosphere throughout the geological record and is vital
for the planet - and hydrocarbon deposition. This is what we want at depth by
increasing surface biomass and its 'fallout'. Ocean circulation changes also
will impact on these processes. Previous research showed that ocean algea
blooms resulted in increased marine 'snow' falling to the ocean floor but it
being reoxidised by deep and mid water life. This was actually - althought they
failed to realise it - a result of short term, local effects. If there is large
areas seeded with additional growth, you get de-oxygenation of deep waters
circulating at the boundary between seafloor and ocean - which yields permanent
removal (not reoxidised) carbon, yielding hydrocarbon deposition. There is no
need to prove that this happens, its an extension of first principles and seen
in the enormity of the  geological record!!  It is not dangerous
either, as the supposedly vulnerable and delicate marine ecosystems are actually
the oldest - therefore they HAVE to be very robust. Increasing surface
photosynthesis in the mid ocean will have little effect on these ecosystems
near to shore, and in fact may help them by taking out poisonous elements in
the water. Now, the big issue with ocean fertilisation is SURFACE HEATING 
and stratification. This actually COOLS the ocean reducing sea level rises - I
predicted this, again from common-sense first-principles, and last year a
physicist proved the idea using a computer simulation for the first time.
Surface photosynthesis simply obviously causes the surface water to heat up due
to increased solar absorption per cm of depth, which automatically raises the
rate of evaporation and heat loss back out from the ocean (the external losses),
although I have simplified a lot here and can explain a number of mechanisms,
already known from EXISTING research. This will cause, unless intelligently and
topographically stimulated, increased hurricanes/storms and rain fall, but this
can be used for good as well as bad. I have to say I find it EMBARRASSING that
I understand the system far better and effectively than paid ocean
'researchers' and can tell them what to do, when I am sitting at home using
basic science and physics principles. Its proof you DONT need a degree, a great
deal of maths or a doctorate or funding to make scientific progress, and it is
proof we are getting bad value for money from those privileged to spend their
lives researching. I have gone beyond them IN MY SPARE TIME. I think it is time
I got a grant, and I know where savings can be made in the current grant
allocation.

Avatar of: Rob-in-Hood

Rob-in-Hood

Posts: 1457

July 21, 2012

I got a great idea, get the heck off oil and burning fossil fuels and find alternatives. The idea that people are coming up with may or may not work to slow climate change but the problem isn't being addressed, and to mess around with the laws of the planet and how it works isn't the way to go. Earth wasn't suppose to tolerate this much CO2, the retarded human race and it's arrogance thinks that he can tame nature and do what he wants to it well sorry to disappoint but that isn't going to work out well for the human race. It needs to think about the planet first and everything else second, but instead it thinks $$$$$ first it is the reason it will fail. At 7 billion people, 4 billion over what the planet can sustain and we still increase the population that doesn't make sense. With all the information that is out there letting people know about our situation is and if we continue what will happen, and little has happened to change we continue to build oil pipelines and promote oil use. We truly are a very stupid race perhaps our extinction is best since we cannot learn from the past.

Avatar of: Ed Rybicki

Ed Rybicki

Posts: 82

August 17, 2012

Has anyone considered the possible role of viruses in subverting this process? It is now (or should be!) well known that the single most abundant type of organism in seawater is viruses - and that they play a VERY important role in short-circuiting carbon flows by providing a "viral shunt", which means dissolved organic carbon (DOC) gets back into circulation a LOT quicker than people thought - or might like.

Basically, any study that seeks to bury carbon on the ocean floor had better look at the effects on, and of, viruses that infect the bloom organisms. Fertilising algal blooms means fertilising the viruses that kill them, which means LIBERATING large amounts of fixed carbon as soluble nutrients for other organisms. Or making carbon dioxide or methane....

Avatar of: Edward R. Mikol

Edward R. Mikol

Posts: 1457

August 17, 2012

The climate does nothing but change.

Interfering with a process we don't fully comprehend is typical human hubris.

Look out for the Law of Unintended Consequences smacking us back harder for meddling with something that we presumptuously assume we can "control".

Caution with "solutions" makes more sense.

Kudzu was introduced to control erosion.

How'd that work out?

Avatar of: Bebe Johnson

Bebe Johnson

Posts: 1457

August 17, 2012

There has to be a way to control the carbon dioxide in the atmosphere on a large scale without adversely affecting the surrounding ecosystems. I hate to say use a machine that will produce pollution but use a machine or bioengineer safer phytoplancton or algal blooms that have controlled and safe products! If the atmospheric carbon dioxide contiues to grow at an unsafe pace use hasty measures (the natural algal blooms) and as we buy time using this method we should be devising and constructing a better system with more favorable outcomes.

Avatar of: Henry K. Barton

Henry K. Barton

Posts: 1457

August 17, 2012

I believe oceans are already saturated of so many human destructive interferences. It is needed to invest in environmentally less invasive and more effective solutions to reduce the carbon emissions to atmosphere such as aneutronic fusion. http://youtu.be/ro5-QYqqxzM

Avatar of: Euclid

Euclid

Posts: 1

August 17, 2012

Does anyone know that a single carbon element requires so many variables to happen in a time sequence is astronomical. Yet carbon is one of the most common elements found in the universe. See below:

Formation of the carbon atomic nucleus requires a nearly simultaneous triple collision of alpha particles (helium nuclei) within the core of a giant or supergiant star which is known as the triple-alpha process, as the products of further nuclear fusion reactions of helium with hydrogen or another helium nucleus produce lithium-5 and beryllium-8 respectively, both of which are highly unstable and decay almost instantly back into smaller nuclei.[54]
This happens in conditions of temperatures over 100 megakelvin and
helium concentration that the rapid expansion and cooling of the early
universe prohibited, and therefore no significant carbon was created
during the Big Bang. Instead, the interiors of stars in the horizontal branch transform three helium nuclei into carbon by means of this triple-alpha process.[55] In order to be available for formation of life as we know it, this carbon must then later be scattered into space as dust, in supernova
explosions, as part of the material which later forms second,
third-generation star systems which have planets accreted from such
dust.[56] The Solar System is one such third-generation star system. Another of the fusion mechanisms powering stars is the CNO cycle, in which carbon acts as a catalyst to allow the reaction to proceed.

Rotational transitions of various isotopic forms of carbon monoxide (for example, 12CO, 13CO, and C18O) are detectable in the submillimeter wavelength range, and are used in the study of newly forming stars in molecular clouds.[57]
What in the wide world of chance coincidences forms so much of these events ever happening by accident.

Avatar of: agelbert

agelbert

Posts: 50

August 18, 2012

The problem with this algae solution is the fact that algae is killed easily by low pH and UVB. Go to the NASA web site Ozone Hole Watch. The ozone hole IS NOT shrinking (see 1979 to 2011 video there) and the bands around the DU (Dobson units of < o r=220) hole edges are thinning all over the globe. No matter what you do to increase photosynthesis in algae or other phytoplankton, it will not work unless you plug that ozone hole up and the reverse is happening. Add to that the fact that the Northwest Passage just opened (the eariest EVER) and the added heating from low ocean albedo of 2 to to 10% in arctic areas that were up to 80% with previous ice cover and the greenhouse is just accelerating. Switching totally to renewable is our only hope.
Please read this article and pass it on with or without attribution. I just want the information out there for the sake of science:
Hope for a Viable Biosphere of Renewables
Off the keyboard of A.G. Gelbert
Google: hope-for-a-viable-biosphere-of-renewables/
Originally published here: DOOMSTEAD DINER

Avatar of: agelbert

agelbert

Posts: 50

August 18, 2012

The problem with this algae solution is the fact that algae is killed easily by low pH and UVB. Go to the NASA web site Ozone Hole Watch. The ozone hole IS NOT shrinking (see 1979 to 2011 video there) and the bands around the DU (Dobson units of < o r=220) hole edges are thinning all over the globe. No matter what you do to increase photosynthesis in algae or other phytoplankton, it will not work unless you plug that ozone hole up and the reverse is happening. Add to that the fact that the Northwest Passage just opened (the eariest EVER) and the added heating from low ocean albedo of 2 to to 10% in arctic areas that were up to 80% with previous ice cover and the greenhouse is just accelerating. Switching totally to renewable is our only hope.
Please read this article and pass it on with or without attribution. I just want the information out there for the sake of science:
Hope for a Viable Biosphere of Renewables
Off the keyboard of A.G. Gelbert
Google: hope-for-a-viable-biosphere-of-renewables/
Originally published here: DOOMSTEAD DINER

Avatar of: agelbert

agelbert

Posts: 50

August 18, 2012

Exactly right!
The problem with this algae solution is the fact that algae is killed easily by low pH and UVB. Go to the NASA web site Ozone Hole Watch. The ozone hole IS NOT shrinking (see 1979 to 2011 video there) and the bands around the DU (Dobson units of < o r=220) hole edges are thinning all over the globe. No matter what you do to increase photosynthesis in algae or other phytoplankton, it will not work unless you plug that ozone hole up and the reverse is happening. Add to that the fact that the Northwest Passage just opened (the eariest EVER) and the added heating from low ocean albedo of 2 to to 10% in arctic areas that were up to 80% with previous ice cover and the greenhouse is just accelerating. Switching totally to renewable is our only hope.
Please read this article and pass it on with or without attribution. I just want the information out there for the sake of science:
Hope for a Viable Biosphere of Renewables
Off the keyboard of A.G. Gelbert
Google: hope-for-a-viable-biosphere-of-renewables/
Originally published here: DOOMSTEAD DINER

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