# posted by Anonymous : Wednesday, 12 October, 2005
CKR, I agree that there needs to be specific ideas in mind in order to address it properly. Without thinking about it, the energies are phenomenal to cause a typical sort of geophysical catastrophe. We cannot yet compete with Nature in most cases. For example, the energy involved in a Category 5 hurricane is something like the equivalent of our entire nuclear arsenal (~10,000 warheads). This is also the energy estimate of the explosion that would result from a medium-sized asteroid equivalent to the one that hit in Yucatan (the ol' supposed dinosaur killer). I suppose we could create some pretty decent avalanches/rockslides, but beyond that I don't know what else would be possible/feasible.
Hi Mark, I too would be interested in where you are going with this. Without going into deep calculations, I heard the tsunami wave was 3-foot high and was moving at 500-miles-per-hr. Instead of using the area of a wave, I used the area of a circle 1000 miles long. This produced roughly 7.2 x 10^9 ft-lb of energy. While this sounds huge, if you use E=mc^2 it become way under a lb, visually speaking, of mass. A nuclear device would convert it’s energy to the seawater by moving the earth under it. The speed of the wave would be dependent on the time it takes to convert the energy. I have seen how fast an explosive charge can build a mountain. A nuclear charge would be real fast. Of course I just did this on a calculator, so my figures could be way off. While it sounds like to me this would be possible, the drilling and placing of a charge would be quite noticeable. It would also depend on how efficient the nuclear device was. I suppose that China has a pretty efficient bomb by now. I say China simply because they were the ones that showed up at the tsunami for a photo-op not us. It also might be in China’s interest to clear a shipping channel of people that are like-minded of the people in the Middle East. As you say it all sounds a little aluminum foil-ly to me.
Hi Mark If the question is: can we produce a tsunami or earthquake, then there is a big problem. While a hurricane has great energy, most of the energy is stored energy. The energy that is released (kinetic) is determined approximately by ½ the diameter of the hurricane times the height, times 1 foot, times the weight of the mass crossing that foot. While 160 mile-an-hour wind causes a lot of acceleration, acceleration times mass would be weight of storm, the amount of lb-foot that is released in the storm can’t be unattainable. I would suppose most of the damage to the buildings and such is caused by the potential energy deference between the storm and the structures. High-speed wind is a low-pressure air. Air inside the structure would be high pressure. Construction practices allow for high load forces to the structure, but when the forces move the other direction failure can occur. This would be the equivalent of pulling nails, much easier than trying to push nails through a structure. While hurricanes cause a high pressure to move in, the velocity of the winds themselves produces a low-pressure area. Getting back to tsunamis and earthquakes, the great things about them are: there is no stored energy. This is what a wave does. It releases energy to travel a distance. The water that came on shore and caused so much damage was not the same water that the earth released its energy into. The only thing that moved was the energy of that portion of the earth that moved. That energy is called kinetic energy. Therefore, all you have to produce is the amount of energy needed to destroy a village and produce a wave at the same time. It doesn’t have to contain the power of a hurricane. Simply the energy contained in the bombing raids over Germany during World War II and the knowledge of how to produce a wave.
"Getting back to tsunamis and earthquakes, the great things about them are: there is no stored energy. This is what a wave does. It releases energy to travel a distance. The water that came on shore and caused so much damage was not the same water that the earth released its energy into. The only thing that moved was the energy of that portion of the earth that moved. That energy is called kinetic energy. Therefore, all you have to produce is the amount of energy needed to destroy a village and produce a wave at the same time"
A very important point. Thank you !
Follow up question that you just made me think of:
Would a tsunami be the best physical world analog effect to the behavior of the kinetic energy itself ? ( which I imagine radiates out in - well - a wave)
Hey Mark, “Would a tsunami be the best physical world analog effect to the behavior of the kinetic energy itself ? ( which I imagine radiates out in - well - a wave)” Actually it is just the opposite. A tsunami is the best physical world digital effect to the behavior of potential energy. It acts like a lightwave or electron. I was trying to show how energy moves without mass. The energy that is moving simply uses the mass of the water to transfer its energy outward. It does this by giving the wave an area of pressure, which is the force between the molecules of the water itself. This pressure is simply transferred to the next area of water in the cycle until it reaches land. I was wrong when I said the wave was 3 foot high. The area containing pressure of the wave started at the bottom of the ocean. The amount of energy needed to produce the wave would then be impossible for me to determine because I am not sure how waves actually form under those conditions. However, the energy is probably stored in the complete depth of the ocean, from top to bottom. That is why water moved out to sea before the huge wave came on shore. Because the same amount of energy has to pass through shallower water, the energy wave has to increase its height accordingly. To do this it needs more water so it is ‘borrowed” from the water ahead of the potential energy wave.