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An excellent BOE analysis here on the cloud making equipment being supported by Bill "the root of all Evil" Gates.
Man! You beat me at it! I had the link ready for posting!!!
But not to worry, I don't think clouds can be rebooted as often, anyway.
Wonder how much energy is going to be spent, fossil fuel burned to reboot those vessels every time they crash.
(BTW, what does BOE stand for?)
I wouldn't really say it's an excellent back-of-an-envelope (BOE) analysis. The author of the post, Willis Eschenbach, doesn't seem to have bothered to read the technical literature on these cloud ships.
The 'technical literature' is effectively this free-to-view paper:
The WUWT post is using a figure for the spray flow rate of 10 tonnes per sec or 10,000 kg/sec. But the paper gives the spray flowrate as either 10 kg/sec or 20 kg/sec depending whether 'spray technology option' 1 or 2 is used. I would imagine the 10 tonnes per sec figure is an order of magnitude figure for the whole fleet of ships.
The WUWT post also estimates that the fleet of 1900 ships can only cover 0.5% of the earth's sea surface. But according to the paper "the area of the sea being treated is taken as 0.18 of the total global sea area", which would be 18%.
Another thing that you pick up from the paper is that one of the main design ideas for the cloud ships is that they are futuristic unmanned sailing ships, using some technology called 'Flettner rotors" (the funnel like objects in the artist's impression, which I've seen some wag liken to 'bong pipes'). The Flettner rotor idea was invented in the 1920s and it is one of those 1920s ideas that has never really caught on, a bit like airships, but I would think it has never been applied for this scale of ship before. The whole sailing ship idea seems to have completely by-passed the WUWT blogger, and he has assumed the spraying equipment would just be installed on normal ships, which I would agree is probably more realistic and certainly quicker to implement, but it isn't what the designers intend to do. The cost estimates in the WUWT post are based on using normal ships and is assuming a spray flowrate of 10 tonnes per sec per ship.
Apparently the people posting the article initially didn't copy their values very well. In that article 10 ships would cover 3800 sq miles and spew 10 tons/sec. He did make an effort to find the company, but didn't find the paper.
I still want to see the jet put this up 3000ft.
Didn't one of the Calypso ships use a sail like this?
"I still want to see the jet put this up 3000ft."
I don't think the spray jet gets up to 3000 ft. From reading the paper I'd say it's more like 65 feet above the top of the spray equipment, as it gives a figure of 20 m/sec for the 'top exit velocity', which I would assume is the velocity of the spray as it comes out. An object with a vertical velocity of 20 m/sec would climb to a vertical distance of 20 m or 65 ft. Then there's a bit in the summary of the paper that says "Micron-sized drops of salt water are ideal condensation nuclei. When they are sprayed into the marine boundary layer, turbulence will move some into the clouds". So it sounds like some of the spray drops at 65 ft are expected to be eventually wafted into the clouds.
"Didn't one of the Calypso ships use a sail like this?"
Jacques Cousteau had a ship called Alcyone which used something like a Flettner rotor, but he called it a turbo-sail. The ship is diesel powered but can switch to the turbo-sail for fuel economy.
Cousteau planned to build a new ship called Calypso II which uses the turbo-sail, but his organisation still hasn't raised the money to build it.
So, this is effectively 3 firehoses.
The original story was much more exciting. 3000ft, 10 tonnes/sec. 65ft and 10kg/sec may actually be less impressive than a fire hose.
I will still be on the picket lines saying "DON'T DO IT!" It is a form of insanity to engineer something to accomplish a task that we can't very accurately identify a need for or determine if we were successful.
Anyone catch this
"I will still be on the picket lines saying "DON'T DO IT!" It is a form of insanity to engineer something to accomplish a task that we can't very accurately identify a need for or determine if we were successful."
My view of geo-engineering is to be fairly neutral towards it. It serves as a useful distraction from the equally insane but far more expensive route of trying to reduce CO2 emissions by 80%. If you want something to serve mainly as a distraction, enginasters are the ideal people to have working on it. Last year Junkscience.com went as far as introducing a policy of promoting geo-engineering but I suspect they were nervous about the possibility of a successor to Kyoto being negotiated at the Copenhagen conference at the end of 2009.
I don't think this cloud whitening idea is going to work. Salter was pushing a very similar idea in a different context, rain-making machines, in the early 00s. He was going to use floating wind turbines to lift up sea spray to a height of 5 to 20 metres and then that was somehow going to form clouds and make rain, solving the world's drought problems. This New Scientist article gives more details:
That idea doesn't seem to have been taken up any of the many countries that might be expected to be interested in such machines, suggesting nobody really believed it.
Salter has an interesting history. He worked on wave power devices and invented a machine called Salter's Duck in the 1970s. Renewable energy got its first big wave of funding in the 70s due to the Oil Crisis, but when the crisis was obviously over in the 80s the funding dried up, only to be revived again about 1990 (and continuing to the present day) by AGW. When he lost his funding in the 80s, Salter convinced himself that he was a victim of a conspiracy by the nuclear industry, because a firm connected with the nuclear industry had been involved in reviewing his reports. His anti-nuclear stance made him popular with the Green lobby and environmental journalists hyped him up into being some sort of Green equivalent of George Stephenson. But as far as I'm aware wave power devices still haven't generated any significant amounts of electricity after decades of development.
Thought this was already happening in Iceland !?
The amount of molecules of H2O vapor that can be entrained in air is limited by the temperature of the air. It takes the addition of heat to convert liquid state H2O into vapor state H2O, and higher air temperature for the air to entrain more H2O vapor state molecules. 539 BTUs per pound of H2O converted would have to be added.
So where is the additional heat that is needed to come from? What is the mechanism that will increase the temperature of the air?
Hint: Try running an evaporative cooler on a day with high humidity. Evaporation of the water will be minor, and the higher the relative humidity, the less the evaporation rate will be.
They can spray all the liquid state H2O particles into the air they want to, but without the required heat needed, those particles of liquid H2O will remain particles of H2O in the liquid state.
The very rich have long indulged a taste for squirting water into the air. They used to call the necessary structures 'fountains' and decorate them with all sorts of mythical trappings. Nothing has fundamentally changed.
Fountains are partly a matter of fashion, partly a matter of powerful people wanting to demonstrate their dominance over the environment and partly perhaps a Freudian reference to the act of ejaculation.
Erm hasn't anyone notices that this is essentially the main earth temperature stabilisation loop. Clouds are pretty darn reflective, maybe up to 70 or 80 % depending on thickness but real hard data is remarkably difficult to find. When temperature rises more water evaporates which rises and forms clouds reducing the overall insolation so with less energy input temperature falls reducing the amount of water evaporated so fewer clouds form leading to more insolation so temperature rises and back round the loop. I hardly think that a few itty bitty ships will make much difference compared to the thousands of square miles of water surface.
Its pretty easy to get a respectable estimate of surface temperature variation for given cloud cover and to calculate the cloud cover / temperature relationship. A HP 67 calculator ran a sufficiently accurate model just fine when I was professionally involved with IR system performance prediction.
No Brit can doubt the reflectivity of clouds after experiencing the common grey autumn / winter / spring days when cloud cover is so heavy that ambient light is severely reduced yet things still feel quite warm. Due of course to reflected thermal radiation from the earths surface. We all know that a clear night means a cold morning 'cos more heat escapes. Except the anti CO2 greenies who really should get out more.
Spot on, Clive. I just wish people would look more at the satellite photos of Earth, which almost invariably show about a third covered with cloud. Given the piddling areas which could be affected by any conceivable number of ships the effects of even a very small natural variation in cloud cover will be dramatically evident in surface temperatures almost immediately.
Clouds represent a positive feedback because the earth doesn't cool as much, but a negative feedback because not as much sun can get through. Some nut might suggests that there is a function involved in the relationship. They might also suggest that the relationship isn't linear and might vary based on a variety of things like: axial tilt, latitude, longitude, time of day, and maybe even altitude.
Surely, Brad, but we must also remember that clouds are not just static objects in the atmosphere blocking and reflecting light but the visible manifestation of major air movements. Over at WUWT someone has been banging on for some time about the fact that, contrary to warmists' belief in a radiative forcing, much to the surface heat energy on Earth gets radiated to space from the top of the atmosphere having been convected there. There appear to be more things under heaven and earth than are dreamed of in their philosophy.
Actually positive / negative feedback is a very unhelpful way of looking at the situation. Its a classic energy balance emergent system. Overall input energy has to equal output energy and for any input energy level a simple vector can be derived to track the cloud cover variation needed to achieve this. Only needs a grey body source model at both ends. The problem is of course that locally its not a pure radiative source / sink situation so for accurate results you need to track the energy vectors of everything else that's going on. Like wind which transports energy horizontally. However in principle its possible to generate a vector array as large as you want and as accurate as you want.
Of course being an emergent system you can't calculate the thing and pin it down on a map. Only way to get the answers is to run it and see. This is a job for analogue computers, or the functional equivalent, not conventional digital machines. Computing section where I worked had a combined analogue and digital machine which was very impressive on the right jobs, easily outrunning a triplet of PDP 11(?). A modern, all digital, development would be ideal here.
Nice thing about emergent systems is that, for small changes at least, exceedingly crude models can generate a sufficiently accurate vector to track enough change for the job. My HP67 was good enough to figure out 0.1 °K target temperature changes when predicting IR imager performance! Its a trivial matter to demonstrate that the cloud feed back loop has ample stability margin to kill off any possible CO2 induced changes however calculated. An irrelevance in practice given that the CO2 band transmission length is at best, about half the height of the troposphere so CO2 changes can't have any effects anyway.
the "here" link does not work there is a v in the http.
why is bill the root of all evil? just curious why you give him so much credit?
Number Watch yeah yeah