Alex Hutchinson on stopping hurricanes

I read an article this weekend in the globe and mail by Alex Hutchinson who reported on several radical strategies for taming hurricanes. Most can be dismissed out of hand, although I am been perhaps a little unfair. On the other hand, we are really not that desperate to try most of them.

In any event, there has been a recent enthusiasm for linking global warming to a projected sharp increase in hurricane numbers. Of course the past two years gax been making nonsense out of that scheme.

What caught my eye though was his description of a deep water pump. This was an area that I had investigated a couple of decades ago with some interest. It had caught my imagination. The important statement however to me was that the transport pipe needed to be only 150 meters in length in order to have an effect on temperature.

The principal concept is to lift cold deeper water to the surface and using that to slightly lower the ambient temperature of the surface water. A very modest drop in surface temperature, around the equatorial waters of West Africa would kill the formation of hurricanes, which we all agree is a good thing.

There is one other major benefit not described. If the pipe goes deep enough, the water lifted will be mineral rich and will stimulate a a massive bloom of sea life down current. The mere fact of lifting enough cold water to create the appropriate temperature will in itself produce a massive fishery in what becomes the Gulf Stream.

Also not appreciated is that the problem of lifting the water is actually not a problem. Thanks to the difference in salinity there is a hydrostatic pressure difference between deep water and the surface that is positive. Certain enthusiasts even wanted to tap this as a source of power. The point is that if one can suspend a stiff walled pipe in the vertical position so that the inlet is a mile below the surface, it is fairly easy to give it a kick and start and maintain a strong flow to the surface. In fact it will come out as a strong jet at the surface.

The engineering problem then resolves to the problem of building long vertical straws that do not collapse and maintain neutral buoyancy. A large cross section is preferred to avoid very much friction. So our engineers need to make a make a long fat pipe, but perhaps not nearly so long as I anticipated twenty years ago. It would be tilted in the current and anchored to the sea bed with the top or outlet positioned a hundred feet below the ocean surface. Can we make it any simpler? When I was thinking about it I was trying to contemplate having a turbine taking energy out of the exit jet of a deep tube.

Instead, with much shorter tubes, we can tolerate a vastly lower exit velocity and no sub sea engineering. It is only a tube! We gain a control mechanism for the hurricane breeding grounds and a huge fishery linked directly to every tube emplacement that will surely pay for maintenance at least.

The question remaining is how to make the tubes themselves. There are many obvious and expensive methods available that could be used. Perhaps initially we will build a thin concrete shell on land with flotation chambers and then float it out to the anchorage. That may be good enough.

We do have one more tool in our bag of tricks. It is that it is feasible to grow calcium carbonate and manganese sulphate on a metal mesh by the application of a low direct current. This is exactly what shellfish do. Thus we can envisage continuously building a metal tube frame out of even low quality rebar and chicken wire and lowering it into the sea as fabricated with the direct current turned on. A mile long tube is no longer an impossibility if it is desired. It takes several months to fill in and it will become thicker and stronger as it matures. Of course flotation will have to be actively managed, but that will be true for any system.

A simple trick, a monster tropical fishery and no hurricanes or typhoons to wipe out our cities. Maybe it can actually work.

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