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Re: Enginasters funded by Bill Gates

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

Re: Enginasters funded by Bill Gates

"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 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.

Re: Enginasters funded by Bill Gates

Thought this was already happening in Iceland !?

Re: Enginasters funded by Bill Gates

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.

Re: Enginasters funded by Bill Gates

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.

Re: Enginasters funded by Bill Gates

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.


Re: Enginasters funded by Bill Gates

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.

Re: Enginasters funded by Bill Gates

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.

Re: Enginasters funded by Bill Gates

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.

Re: Enginasters funded by Bill Gates

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.


Re: Enginasters funded by Bill Gates

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