[The Polymath]

cyclonebuster, on 13 May 2011 - 09:07 AM, said:

Just enough to make it come out of the tunnel about 5 mph. What do you get?

That is what he asked you. Haven't you worked it out ahead of time?

[cyclonebuster]

The Polymath, on 13 May 2011 - 09:43 AM, said:

That is what he asked you. Haven't you worked it out ahead of time?

Nah! I just tested a model I built of it and videoed it working and posted it on youtube. I'll work it out later.

[cyclonebuster]

Seems the good professor worked it out for me.

quote:
Yes, I have spoken with Patrick, and, yes, a scheme somewhat like the one he describes could weaken hurricanes threatening places like Miami that have strong western-margin currents just offshore. There are, however, numerous qualifications.

The scheme that we discussed involved an array of several rows devices across the Gulfstream. Each device would be a rectangular duct 140 m long and 10 by 14 m in cross section. Normally the devices would be moored horizontally at a depth of 100m with their long axes aligned with the current flow. They would be nearly neutrally buoyant. When a hurricane approached, ballast at the downstream end of the channel would be released, allowing the device to float up to a 45 deg angle. Cold water entering the upstream end would flow up to the surface and mix with the warmer water there. Since the mixture would be negatively buoyant, it would sink. But mixing due to several (3-10) lines of these devices could cool the surface waters of the Gulfstream by 1-2C, enough to weaken an Andrew-like hurricane from category 5 to category 3. A rough calculation indicates that a device every 100 m on each line of moorings (~1000 devices per ~100 km line) and 3-10 lines of moorings would be required. My guess is that it would cost $250K to fabricate and deploy a single device, but there might be economies of scale. One might also be able to optimize the size and spacing of the devices.

Let's say that careful calculation told us that 4 lines of 1000 devices each would do the trick. At $0.25M per device, the cost works out to 4*1000*($0.25M) = $1000M. The actual cost might range from a few hundred million to a small multiple of a (US = 1000M) billion. One would want to do a detailed simulation before defining the scope of the project, but the basic notion is conversion of some of the kinetic energy of the Gulfstream into gravitational potential energy of the mixed water column. Again, I've not done that detailed simulation, only back-of-the-envelope calculations.

Activation of the array would require accurate forecasting since it would take several days for the effect to make its way from south of the Dry Tortugas (optimum location for protecting the maximum amount of shoreline) to the landfall point.

South Florida gets hit by a category 4 or 5 hurricane at every few years, but the really damaging ones like Andrew tend to be once-a-generation events, or less frequent. The array would need to be deployed and maintained for a long time between activations that actually safeguard property, although false alarms would not be particularly costly. Annual maintenance could easily exceed 10% of initial deployment cost. Bear in mind that Key West to Jacksonville is the only stretch of US coastline where this strategy would work. The other vulnerable sites, Houston-Galveston and New Orleans, lack the necessary strong offshore currents. While Georgia and the Carolinas also experience many hurricane landfalls and have the Gulfstream offshore, most of these cyclones are already weakening because of vertical shear of the horizontal wind so that a second installation north of Jacksonville would be much less useful.

There has been a lot of talk about using wave and current energy to cool the ocean ahead of hurricanes. My general conclusion is that while these ideas might be made to work, the proponents underestimate the scope of the required effort, as well as the political will and recurring cost necessary to keep the project going in the long intervals between really damaging hurricanes. Skeptic that I am, I think that wiser land-use policy and more rigorous building standards are much more cost-effective and more politically feasible. A proof-of-concept that might entail deploying a half dozen devices has some appeal, but I think that there are more promising ways to spend disaster-prevention money.

Best regards,

Hugh Willoughby


http://www2.fiu.edu/.../willoughby.htm

[Moontanman]

Well he worked it out all except the environmental consequences, such a diversion would affect far more than just cyclones, weather in Europe, world wide sea water circulation, oxygen levels in the deep sea, sea life, and by affecting weather land life as well. Such a project would have far reaching consequences that would make hurricanes look trivial.

[cyclonebuster]

Moontanman, on 16 August 2011 - 02:52 PM, said:

Well he worked it out all except the environmental consequences, such a diversion would affect far more than just cyclones, weather in Europe, world wide sea water circulation, oxygen levels in the deep sea, sea life, and by affecting weather land life as well. Such a project would have far reaching consequences that would make hurricanes look trivial.

Weather in Europe would return to what it was prior to the industrial revolution. World wide sea water circulation will stay the same. Oxygen levels would stay the same but Co2 levels will lower and that is good for the calcium shelled organisms because carbonic acid won't dissolve their shells anymore.Sea life would flourish because they are too hot now since global ocean temps have risen 1.5 degrees C in the past 110 years. This idea restores those temperatures because they have the unique ability to regulate SSTs to what we determine will be the best for sea life and the coral reefs that suffer from coral bleaching because of the oppressive heat. They have to try and eek out an existence in waters that are to warm now. The heat we are making now is making hurricanes look trivial especially with what is going on at the North Arctic Ice cap. This idea has the opposite effect of what you may think!

[CraigD]

cyclonebuster, on 15 August 2011 - 11:36 AM, said:

Seems the good professor worked it out for me.
...
The scheme that we discussed involved an array of several rows devices across the Gulfstream. Each device would be a rectangular duct 140 m long and 10 by 14 m in cross section. Normally the devices would be moored horizontally at a depth of 100m with their long axes aligned with the current flow. They would be nearly neutrally buoyant. When a hurricane approached, ballast at the downstream end of the channel would be released, allowing the device to float up to a 45 deg angle. Cold water entering the upstream end would flow up to the surface and mix with the warmer water there. ...

Best regards,
Hugh Willoughby

Another interesting scheme I read about some years ago involves spreading a thin layer of insulation (in the form of an oil slick, or more exotic, of the super-absorbent material used in disposable diapers) over a large area of ocean in a hurricane’s path. Like Willoughby’s water mixing scheme, this cuts the hurricane off from its supply of power from the warm ocean surface. Such a scheme has an advantage over Willoughby’s roughly 4000 140x14x10 m submerged ducts, in that it could cost much less than the ducts’ roughly US$ 1 billion, though the ducts might prove less expensive in the long run, as once installed they should need only modest maintenance. Their only moving parts are those of the ballast systems that tilt them to 45° when a hurricane is approaching.

If attention by successful business people is an indication, Willoughby’s scheme (or I should say, the scheme he describes, as I don’t think he’s its inventor) should be taken seriously: according to this article, Bill Gates of Microsoft fame, along with a group of other investor applied for patents on the technology in 2008-2009.

Moontanman, on 16 August 2011 - 02:52 PM, said:

Well he worked it out all except the environmental consequences, such a diversion would affect far more than just cyclones, weather in Europe, world wide sea water circulation, oxygen levels in the deep sea, sea life, and by affecting weather land life as well. Such a project would have far reaching consequences that would make hurricanes look trivial.

The hurricane weakening scheme Willoughby describes would only be activated when a hurricane was approaching a coast protected by the array of submerged devices, and remain active only until the weather system’s cyclonic energy had dissipated to a safe level – days, or at most, weeks.

Such a brief ocean water mixing would, I think, have only a slight environmental impact, less than that of a hurricane close approach or landfall. Hurricane landfalls on populated and/or industrial coasts can do severe environmental damage from debris, spilled oil and sewage, etc. So I’d say that, along with saving lives and (maybe – this is the real deal-maker/breaker question) money, Willoughby’s scheme would protect the environment.

cyclonebuster, on 16 August 2011 - 04:07 PM, said:

Weather in Europe would return to what it was prior to the industrial revolution. World wide sea water circulation will stay the same. Oxygen levels would stay the same but Co2 levels will lower and that is good for the calcium shelled organisms because carbonic acid won't dissolve their shells anymore.

I think you misunderstand Dr. Willoughby, CB.

Hurricane protection systems like Willoughby and others describe aren’t intended to change global or local environments, just change the short-term weather, that is, reduce the effects of hurricanes.

I think there’s a basic heat mechanical flaw with using this scheme to affect global air temperature. Mixing warm and cold water doesn’t remove heat from it. Warm surface water forced to a lower depth will rise downstream of the array of ducts, so the effect of air temperature is not to reduce it globally, but to move heat slightly. This is just what’s needed to weaken a hurricane, but not to reduce global warming.

We had a lot more discussion of this subject in your 2007 thread Underwater Suspension Tunnels Prevent Global Warming.

[cyclonebuster]

CraigD, on 20 August 2011 - 01:55 AM, said:

Another interesting scheme I read about some years ago involves spreading a thin layer of insulation (in the form of an oil slick, or more exotic, of the super-absorbent material used in disposable diapers) over a large area of ocean in a hurricane’s path. Like Willoughby’s water mixing scheme, this cuts the hurricane off from its supply of power from the warm ocean surface. Such a scheme has an advantage over Willoughby’s roughly 4000 140x14x10 m submerged ducts, in that it could cost much less than the ducts’ roughly US$ 1 billion, though the ducts might prove less expensive in the long run, as once installed they should need only modest maintenance. Their only moving parts are those of the ballast systems that tilt them to 45° when a hurricane is approaching.

If attention by successful business people is an indication, Willoughby’s scheme (or I should say, the scheme he describes, as I don’t think he’s its inventor) should be taken seriously: according to this article, Bill Gates of Microsoft fame, along with a group of other investor applied for patents on the technology in 2008-2009.


The hurricane weakening scheme Willoughby describes would only be activated when a hurricane was approaching a coast protected by the array of submerged devices, and remain active only until the weather system’s cyclonic energy had dissipated to a safe level – days, or at most, weeks.

Such a brief ocean water mixing would, I think, have only a slight environmental impact, less than that of a hurricane close approach or landfall. Hurricane landfalls on populated and/or industrial coasts can do severe environmental damage from debris, spilled oil and sewage, etc. So I’d say that, along with saving lives and (maybe – this is the real deal-maker/breaker question) money, Willoughby’s scheme would protect the environment.


I think you misunderstand Dr. Willoughby, CB.

Hurricane protection systems like Willoughby and others describe aren’t intended to change global or local environments, just change the short-term weather, that is, reduce the effects of hurricanes.

I think there’s a basic heat mechanical flaw with using this scheme to affect global air temperature. Mixing warm and cold water doesn’t remove heat from it. Warm surface water forced to a lower depth will rise downstream of the array of ducts, so the effect of air temperature is not to reduce it globally, but to move heat slightly. This is just what’s needed to weaken a hurricane, but not to reduce global warming.

We had a lot more discussion of this subject in your 2007 thread Underwater Suspension Tunnels Prevent Global Warming.

It allows the heat to be removed from the planet to space since less water vapor will be formed in the atmosphere thus allowing the planet to cool more.They also remove fossil fuel GHG's which will also allow more heat to escape to space.

[CraigD]

cyclonebuster, on 20 August 2011 - 05:32 AM, said:

It [cooling the surface of a section of the ocean by mixing surface and deep water] allows the heat to be removed from the planet to space since less water vapor will be formed in the atmosphere thus allowing the planet to cool more.They also remove fossil fuel GHG's which will also allow more heat to escape to space.

Can you back this up with a link or reference, cyclonebuster

[cyclonebuster]

CraigD, on 21 August 2011 - 09:31 PM, said:

Can you back this up with a link or reference, cyclonebuster

Sure once you understand this then you it will come to you!

http://kitekinto.hu/...833%22%22%22%22