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Could nutrients from the deep could help remove carbon dioxide from the air?
Could mighty pumps be installed in the ocean to mix up the waters and cool the planet? At least some scientists and businessmen believe so — but the idea is controversial.
Posted by Nicola Jones on September 26, 2007
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I'm afraid that messing with this very longterm water circulation can be very dangerous. Within a few weeks you may change the gobal water circulation for ever. Just think what would happen to europe if the gulfstream weakens or vanishes. Don't mess with nature!
Posted by: Stefan Breuer from Passivhaus-konkret | September 26, 2007 06:55 PM
Regardless of the way it is published or adressed every word that comes from Nature has a strong impact all over the world. If they have names such as Lovelock the impact is obviously even greater. Such controversial proposals require at least some in-depth studies that support such assumptions. To simply state that this is just a proposal and has NO scientific validation is awkward and absurd especially when it comes from highly reputed science personalities. This letter simply should not have been submitted and should not have been published. It does not contribute to finding solutions to climate change problems and supports tecnocratic senseless behaviour that has led us to the present state.
Posted by: João Cleto | September 27, 2007 11:37 AM
What about the eutrophication that might be caused by the algal blooms which can pose potential threat to the ocean fauna. Other problem could be that algal bloom may cause sunlight penetrating in to the ocean depths which could again disturb the life under sea. Please DON'T TRY TO ALTER mother nature. We need to change our attitudes, life styles. The external things cannot be changed. Its nature. We can change ourselves and try to reduce further global warming.
Posted by: Midhun Korrapati | September 27, 2007 01:41 PM
Even before the proposed algal fixation of CO2 takes place, a microbial degradation of the organic nutrients is likely to happen under the aerobic conditions at the oceans surface. As a consequence, CO2 may rather be released due to the highly increased microbial assimilation than fixed by the algae. Therefore, every single gram of nutrient brought up from the deep sea may directly be converted to CO2.
Posted by: Thomas K | September 27, 2007 02:03 PM
Carbon tends to follow nutrients in the ocean. So the nutrient-rich deep waters that they are proposing to bring to the surface will also be rich in carbon. And that carbon could be transferred back into the atmosphere.
It looks like Lovelock has been toking on a different kind of pipe here - and Rapley has been inhaling the secondary smoke.
Posted by: Alex Duggan | September 28, 2007 08:18 AM
Rapley hasn't first-authored a research paper since 1984. Lovelock has been living off a strained metaphor for decades. They are not climate researchers on the cutting edge. Their scheme has not been peer-reviewed, is fundamentally flawed as others point out and does not deserve this publicity.
It's like Linus Pauling and Vitamin C all over again.
Posted by: Jim Cross | September 28, 2007 11:47 AM
I have a solution to world hunger, too! We could all eat Moon cheese. Of course, we don't actually know for certain whether or not there is any cheese on the Moon. But hey, I have a PhD in a vaguely related subject area so my idea must be valid.
Oh, I'm sorry, that should have been "vapid", just like this scheme...
Posted by: Bob Jones | September 28, 2007 01:31 PM
thanks for the information.
Posted by: Wellnesshotel Bayern | September 28, 2007 10:36 PM
To say that we must not try to alter Mother Nature is ignorant, as that is what has got us into this mess. It is the understanding of the Earth's physical processes and our impact on them that will allow us to better tackle climate change. A nice thought to hope that if we just reduce our emissions the problem will go away; what about the damage already done.
The processes that control our climate have already been affected. Long term cycles have accelerated and we have experienced the results. Perhaps solutions can be found by looking at what has happened in the past and the mechanisms the Earth has used to 'heal' itself. If we are to mitigate some of the human impact of climate change, we cannot wait for these natural remedies to kick in.
After all, global warming will not remain forever. What about another ice age?
Posted by: Darren Cahill | September 29, 2007 11:31 AM
Energy Differentials
You are trying to do the wrong thing---or the right thing for the wrong reasons.
What the oceans have in abundance, is layers of water at significantly different temperatures, which change suddenly with depth. This is the "stratification of the thermoclines". A pump that circulates these waters should be able to generate energy though heat-exchangers at the surface--more than enough to compensate for the pumping and the minimal friction.
This is really the next big energy resource, after fossil fuels dry up. Carbon sinking or reduced emissions will be at best a by-product.
Posted by: Dr. Saadya Sternberg | September 30, 2007 08:16 AM
Adding to the CO2 gas release adverse effect of such a messing-up with the ocean’s water one can consider a chemocline (where oxygenated water meets
water permeated with hydrogen sulfide (H2S) generated by bottom-dwelling anaerobic
bacteria) breaching problem which may occur if such a pumping deep waters up activity would take place.
What if the chemocline separating the H2S-rich deepwater from
oxygenated surface water could have floated up to the top
abruptly. The horrific result would be great bubbles of toxic
H2S gas erupting into the atmosphere.
(Scientific American - 2006 - volume 295 - number 04 – October)
Posted by: Sergei Morse | October 1, 2007 01:30 AM
The idea of pipes in the ocean to moderate climate was proposed for somewhat different reasons many years ago. At that time, the concern was the end of our present interglacial climate. The author (my memory fails me but I think it was a well known astronomer with a flair for speculation) proposed circulating warm surface waters to the deep. This was to build up a storehouse of heat and so moderate future cooling.
Some comments posted have suggested a doomsday scenario of messing around with ocean circulation. Some of these are no less outlandish than the proposal itself.
In terms of our present concerns with climate change, longer term solutions with costs and benefits are well known. Throttling down our profiligate consumption of fossil fuels, and improving our agricultural and land use practices will produce a more sustainable technological society.
Posted by: Daniel Conrad | October 1, 2007 02:27 PM
To mess around with a natural system that is already the planet's major carbon sink is downright scary!
It stretches credibility to imagine that it is feasible to increase the rate of carbon absorption by the oceans without causing adverse effects such as accelerated sea level rise. Apart from anything else, this is a fix rather than a cure and provides no incentive to mankind to clean-up its act.
Posted by: Nigel Jennings | October 1, 2007 06:32 PM
To enhance the effectiveness by 3 to 10 times, we need to add small amounts of iron to the nutrient rich water. Iron is usually the one ingredient missing. Iron alone causes algae blooms. This also is the bottom rung of the food change. Over time, as the food chain builds, with some assistance, we can also create new areas for fishing. Perhaps fishing associations may be willing to help fund this effort, since we have depleted 80%+ of our global fish stock.
Posted by: Phil | October 1, 2007 07:24 PM
And some people say that scientists have no sense of humour...
PS: Just got a letter from my Girlfriend, it has no Scientific Validation, should I submit it just in case?
Posted by: Amuneke Chipenda | October 3, 2007 03:09 PM
If wave power could power such a nutrient pump capable of sustaining ocean life in the tropics, each pump could become the engine for a fish farm. If this became widely implemented, it could also mitigate hurricane activity. See, I can speculate with the best :)
Posted by: Daniel Kellis | October 3, 2007 03:56 PM
One thing is common to most comments, people have no idea what the ocean is like. If the situation is dramatic indeed, some new ideas how to combat greenhouse gases are welcome. Lovelock and Rapley's idea is untested, but that doesn't mean it couldn't work. Another possibility could be to speed up chemical weathering, because that is the most powerful natural mechanism by which nature removes CO2 from the atmosphere. It can be done by spreading fine-grained olivine, and let nature take care of the CO2 removal.
Posted by: Schuiling, R.D. | October 4, 2007 01:26 PM
Ocean pipes could help the Earth cure itself – a flawed concept?
(This is an extended version of a response submitted to Nature’s Correspondence. It was not published as Nature had already received a number of substantive responses). Lovelock and Rapley (Nature, 449,403, 2007) put forward the idea that by pumping up nutrient rich deep oceanic water, the subsequent stimulation of planktonic photosynthetic production would give rise to a very significant drawdown atmospheric CO2. The concept is flawed scientifically on two accounts. Planktonic photosynthesis results in the assimilation of inorganic nitrogen and CO2 in a ratio which has a modal value in the region of 6.6 – the so-called Redfield ratio. A fraction of the organic particles that arise as a consequence of photosynthetic production, sink into the deeper parts of the ocean. The C/N ratio of these particles is somewhat higher than the Redfield ratio (C/N ratios of 10 or greater) as there is some fast decomposition of the nitrogen (and phosphorus) rich organic components before the particles reach deep water. The particles are eventually decomposed in the deeps, with the production in inorganic nutrients, along with CO2. If this water, now enriched in inorganic nitrogen (and phosphorus), were brought to the surface, it would indeed stimulate planktonic photosynthesis and result in the assimilation of CO2. However, the upwelled water is not only enriched in inorganic nitrogen but also CO2 produced at the same time, the latter being slightly in excess of the Redfield requirement due to the elevated C/N ratio of the settling particles. Thus, rather than drawing down atmospheric CO2 from the atmosphere, there would be export of CO2. The situation in fact would be worse than this. The cold deep water when it was formed would have been in equilibrium with atmospheric CO2, if brought to the surface the upwelled water must warm up, otherwise it would simply sink back again; this would reduce the solubility of CO2, resulting in further export of oceanic CO2 into the atmosphere. .
Further, from the engineering point of view the concept is infeasible – to lift up a 10m diameter column of dense (cold) 50m (the sort of lift that would be needed) means a net lift of about 10 tonne and would almost certainly collapse a flexible tube, if pumped from the top, or balloon it out if pumped from the bottom.. A ribbed tube would simply concertina
Even if the engineering problems could be solved and the system made cost effective, both of which seem very doubtful, the proposal would have the reverse effect of that claimed.
Peter J. le B. Williams
School of Ocean Sciences,
University of Wales, Bangor,
UK
Posted by: Peter Williams | October 10, 2007 08:32 PM