Re: [geo] Carbon budget/removal in NYTimes interactive

[Greg Rau]

Christoph et al.,While the ocean does contain a lot of untapped energy and CO2 
removal potential, I share your concerns about the difficulties of tapping into 
photosynthetic energy to do this for the reasons you state. That's not to say 
that there couldn't be clever ways of harnessing marine macro/micro flora, but 
it would require careful management of N, P, Fe, Si, O2 etc to effect the 
desired CO2 management while not disrupting existing surface ocean 
ecosystems/biogeochemistry.
As for putting the deep ocean to use, in addition to a nutrient and CO2 
source/sink it is also a very large heat sink. When coupled via OTEC to the 
(growing) surface ocean heat source you've got something like 10TW of 
continuous, potential, deliverable electrical power even considering a 3% OTEC 
energy conversion efficiency. Ways of performing such OTEC that vertically move 
only heat (not seawater) in a closed cycle have been proposed.  When coupled 
with a CO2-consuming method of generating H2, you've got a global scale 
negative emissions energy delivery system whose CDR potential could be 50Gt 
CO2/yr while delivering CO2-free fuel equivalent to >3X annual global gasoline 
consumption. It also directly and beneficially cools and alkalizes the surface 
ocean - https://agu.confex.com/agu/fm16/meetingapp.cgi/Paper/121574 ;  I can 
provide further details if interested. Nor are we restricted to OTEC since any 
source of non-fossil electricity can make C-negative H2.

Anyway, the NYT's CDR model restriction of 12 Gt CO2/yr by 2100 would indeed 
seem unduly pessimistic, esp if we allow ourselves to think beyond land-based 
and biology-based methods of saving the planet. Now would seem a good time to 
expand the search and find out what if any viable options we actually have, 
considering the scale and urgency of the problem.
Greg


  From: Christoph Voelker 
 To: Robert Tulip ; "geoengineering@googlegroups.com" 
 
 Sent: Friday, September 8, 2017 12:14 AM
 Subject: Re: [geo] Carbon budget/removal in NYTimes interactive
   
 Dear Robert, I am a physicist, not an engineer, so I can't really judge how 
feasible it is to pump half a percent of the total volume of the ocean (this is 
what I got from my nutrient calculations, and I think they are correct) from a 
depth of 1000m or more up to the surface every year by tidal pumping, but I 
have to admit that I am sceptical. 
 I also cannot fully follow your argument about the concentration of nutrients, 
but I think your numbers are not correct. The average concentration of nitrate 
in the deep ocean is around 30 micromol/L (not 3 ppm, which is neither correct 
in mol/mol, nor in volume/volume); and that of phosphate is not the same, but 
around 15 times less, i.e. around 2 micromol/L. Anyway, there is a much more 
fundamental problem with the approach that you are suggesting that is 
independent of its scale: When you pump up deep ocean water to get at the 
nutrients therein, you also pump up water that contains more dissolved 
inorganic carbon than surface ocean water. On average deep ocean water contains 
as much more dissolved carbon as you can fix with the nitrogen/phosphorus 
contained in it (again assuming a constant Redfield C:N:P ratio); this is 
because the higher carbon content in the deep ocean has been brought there 
mostly by the sinking and subsequent remineralisation of organic matter. Of 
course, with the nutrients that you bring up, most of that carbon will again be 
fixed in your algal biomass and can then be disposed of (whereever, maybe as 
biochar). But: That then leaves almost no room for using the algae to fix 
additional carbon from power plants, as you suggest. 
  So in effect what you do with that approach is: You pump up the carbon that 
has been stored in the deep ocean by the natural biological pump, which without 
anything else would increase CO2 in the surface. Then you fix this carbon in 
biomass and store it on land. In the end you have only shifted carbon from the 
deep ocean to the storage on land, and have achieved very little, if anything 
at all in terms of fixing the fossil-fuel-generated carbon. The only way out of 
this that I see is to use algae with an elevated C:N and C:P ratio compared to 
the Redfield ratio, because then you can fix more carbon than you bring up. 
  But then again, I would be sceptical about the possible scale that you 
mention, from my back-of-the-envelope calculation of the nutrient requirements 
from my last email. 
  Best regards, Christoph
  
 On 08.09.17 01:15, Robert Tulip wrote:
  
 
 Thanks Cristoph. Deep Ocean Water, with volume about a billion cubic 
kilometres below the thermocline, has about three ppm nitrate and phosphate, 
about 3000 cubic kilometres of each, as I understand the numbers. Tidal pumping 
arrays along the world's continental shelves could raise enough DOW to the 
surface, mimicking natural algae 

[geo] AW: Possible paper of interest

[Michele, Jürgen]

Dear Mike!
The idea is not to waste energy, but to use the existing surface energy in 
front of a hurricane.
Very little energy is needed to start an updraft if conditions “are right”.
K. Emanuel termed our publication a ”nutty idea”, but also said, that one 
should give Michauds “energy generation tower” - 
http://vortexengine.ca/index.shtml  a try.
To me there are not basic differences between dust devils, fog devils, hay 
devils, fire devils, water spouts, tornadoes and hurricanes. The differences 
lie in the supply intensity – high surface temperature and more important high 
moisture. These days Katia is a special case where the hurricane is more or 
less a local event, which started from a local instability.
The idea is calling for a wall less chimney. Condensation creates a vacuum and 
will suck in air from the ground. Any free jet is an expanding one cell vortex. 
The condensate will be centrifuged out making the center less dense. This air 
will rise to an equilibrium level which can be as high as the level of 
tornadoes or hurricanes. A higher momentum is needed to bring air masses well 
above that equilibrium level, to penetrate the inversion layer and to create an 
outflow as a hurricane does. The rotation of the jet may be created to be 
cyclonic or anticyclonic. In the meantime I learned that most tornadoes are 
cyclonic – only about 10% are anticyclonic.
Again this will cool the surface waters and an approaching hurricane may be 
reduced in intensity or directed not to hit land.
By the way we were pretty successful using a free jet to fight cyanobacteria in 
a reasonably large lake. With only 6kW we realized total destratification and a 
reduction of phosphorus by 5.4t. The method showed up to be sustainable.
Regards Juergen Michele

PS: 
I had only a glance at the paper you attached. I checked it for the word 
“condensation”. It is not in that article – at least the search engine could 
not find it.
… Ike was even 1000km …

Prof. Dr.-Ing. Juergen Michele
Jade Hochschule
Wilhelmshaven

Tel.: 0049 4461 83043
E-Mail:juergen.mich...@jade-hs.de
Homepage: http://michele.staff.jade-hs.de/
https://www.researchgate.net/profile/Juergen_Michele/contributions

Privat:
Soestestr. 3
26419 Schortens


Von: Michael MacCracken [mmacc...@comcast.net]
Gesendet: Donnerstag, 7. September 2017 18:01
An: Michele, Jürgen
Cc: Stephen Salter
Betreff: Possible paper of interest

Dear Juergen--Regarding your note about how to potentially modify a
hurricane, I thought you might be interested in the attached paper from
60 years ago in Science as it does some analyses of the energetics of
trying to alter natural systems on local to regional scales.

To get a sense of the amount of energy a large hurricane is processing,
consider a diameter of maybe 600 km and an average rainfall rate over
this area of 20 cm/day of rain, multiply by the heat release of
condensation/evaporation, and, when I did this 50 years ago or so, it
comes out, as I recall, to a very large number (roughly equivalent to
several megaton explosions per minute). So, this is not the rate of
energy that is lost (which is likely several per cent of this rate), but
the rate of conversion from latent to kinetic and potential energy,
etc.--a very large number. Estimating the rough energetics of proposals
like modifying hurricanes can give a real sense of the challenge
involved (e.g., that exploding a megaton size nuclear bomb likely would
not do very much to a system like currently being experienced).

Regards, Mike MacCracken


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[geo] Early warning

[Stephen Salter]

Hi All

I would like some help with a question which I hope will be of interest 
to some of you who can get access to historical meteorological records.


We want to know how far in advance of a hurricane starting can we make a 
reasonably accurate prediction that this will happen.


The obvious indicator is sea surface temperature anomaly.  But the 
vertical temperature gradient, the magnitude and direction of wind and 
current may also give cues. There may also be Boolean combinations of 
information from other regions, El Niño, jet stream patterns, Arctic 
ice, bird migration even phytoplankton density.


The output might be graphs with a horizontal axis of weeks or months and 
the vertical one being the prediction usefulness of any indicators 
giving a total prediction score.   This would allow people in control of 
flotillas of spray vessels to have them in the right place.


Next would be using climate models to predict what would happen if we 
sprayed in response to a false prediction.


Thank you for three corrections, so far, to the estimate of vessel 
numbers.  More would be welcome.


Stephen


--
Emeritus Professor of Engineering Design. School of Engineering, 
University of Edinburgh, Mayfield Road, Edinburgh EH9 3DW, Scotland 
s.sal...@ed.ac.uk, Tel +44 (0)131 650 5704, Cell 07795 203 195, 
WWW.homepages.ed.ac.uk/shs, YouTube Jamie Taylor Power for Change


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Re: [geo] Carbon budget/removal in NYTimes interactive

[Christoph Voelker]

Dear Robert,

I am a physicist, not an engineer, so I can't really judge how feasible 
it is to pump half a percent of the total volume of the ocean (this is 
what I got from my nutrient calculations, and I think they are correct) 
from a depth of 1000m or more up to the surface every year by tidal 
pumping, but I have to admit that I am sceptical.
I also cannot fully follow your argument about the concentration of 
nutrients, but I think your numbers are not correct. The average 
concentration of nitrate in the deep ocean is around 30 micromol/L (not 
3 ppm, which is neither correct in mol/mol, nor in volume/volume); and 
that of phosphate is not the same, but around 15 times less, i.e. around 
2 micromol/L.


Anyway, there is a much more fundamental problem with the approach that 
you are suggesting that is independent of its scale: When you pump up 
deep ocean water to get at the nutrients therein, you also pump up water 
that contains more dissolved inorganic carbon than surface ocean water. 
On average deep ocean water contains as much more dissolved carbon as 
you can fix with the nitrogen/phosphorus contained in it (again assuming 
a constant Redfield C:N:P ratio); this is because the higher carbon 
content in the deep ocean has been brought there mostly by the sinking 
and subsequent remineralisation of organic matter. Of course, with the 
nutrients that you bring up, most of that carbon will again be fixed in 
your algal biomass and can then be disposed of (whereever, maybe as 
biochar). But: That then leaves almost no room for using the algae to 
fix additional carbon from power plants, as you suggest.


So in effect what you do with that approach is: You pump up the carbon 
that has been stored in the deep ocean by the natural biological pump, 
which without anything else would increase CO2 in the surface. Then you 
fix this carbon in biomass and store it on land. In the end you have 
only shifted carbon from the deep ocean to the storage on land, and have 
achieved very little, if anything at all in terms of fixing the 
fossil-fuel-generated carbon. The only way out of this that I see is to 
use algae with an elevated C:N and C:P ratio compared to the Redfield 
ratio, because then you can fix more carbon than you bring up.


But then again, I would be sceptical about the possible scale that you 
mention, from my back-of-the-envelope calculation of the nutrient 
requirements from my last email.


Best regards, Christoph


On 08.09.17 01:15, Robert Tulip wrote:

Thanks Cristoph.
Deep Ocean Water, with volume about a billion cubic kilometres below 
the thermocline, has about three ppm nitrate and phosphate, about 3000 
cubic kilometres of each, as I understand the numbers. Tidal pumping 
arrays along the world's continental shelves could raise enough DOW to 
the surface, mimicking natural algae blooms, to fuel controlled algae 
production at the scale required for seven million square kilometres 
of factories.  Piping CO2 from power plants etc out to ocean algae 
farms could clean up all the polluted air of the world.

Robert Tulip



*From:* Christoph Voelker 
*To:* geoengineering@googlegroups.com
*Sent:* Friday, 8 September 2017, 8:43
*Subject:* Re: [geo] Carbon budget/removal in NYTimes interactive

I must admit that I am getting skeptical when I hear numbers in that 
order of magnitude:
The total net primary production in the oceans presently is about 50 
Gt carbon, and 80% of that is converted back into inorganic carbon 
(and nutrients) by heterotrophs before it gets a chance to sink out 
from the sunlit upper layer of the ocean. The roughly 10 Gt carbon 
(some newer works even estimate just 6 Gt carbon) that sink out have 
to be balanced by the upward mixing of nutrients (and a little bit by 
atmospheric deposition of bioavailable nitrogen and phosphorus) in the 
Redfield ratio of about 106:16:1 of C:N:P.
So, if you want to remove 20 Gt carbon per year from the atmosphere, 
you'd have to increase the nutrient supply to the total surface ocean 
by a factor of three, maybe four. Maybe I am a bit too pessimistic 
here, because there are species like Sargassum which have a higher 
C:N:P ratio than the average phytoplankton, so you get somewhat more 
carbon per nitrogen/phosphorus. But even if it is just doubling, I 
can't imagine that you can sustain such a nutrient consumption by 
fertilizing from outside the ocean (especially since phosphorus is 
scarce already now), you'd have to tap into the inorganic nutrients 
stored in the deep ocean. How long can you do that?
If we assume that we harvest all the 20 Gt carbon in algae from these 
factories and do something durable with them (to minimize lossed 
through heterotrophy and problems with creating oxygen minimum zones), 
we effectively remove nitrogen/phosphorus from the ocean. How much is 
that per year?
Let us for simplicity assume Redfield