So, in another thread, it was shown how nuclear bombs do not have the oomph to deter hurricanes.
But what about tropical depressions in their early stages and nuclear missiles. Since nuclear missiles are capable of heating up a lot of air and can stay air borne for long durations, Is it possible to direct the heated exhaust (and hence dryer air) to the tropical depression for say hours/days until the structure of the depression is dissipated ? (assume the nuclear missile is doing circles inside the depression)
There has never been an actual missile that could do this. The USA considered it in the 1950s and decided it was too dangerous and stupid to build, and Russia is currently developing one and finding out the hard way that it is too dangerous and stupid to build.
I may be talking out of my left elbow, but I think that heating the air in the anticyclone enough to affect the pressure noticeably would necessitate very rapid heating. The air isn’t in a closed box, so raising T raises the PV product, not only P (some of the raise of PV will simply be expansion up; there will be expansion “sideways” once the pressure in a spot gets higher than in neighboring ones).
PV=nRT , yeah?
In a system with rigid walls: V is fixed. n and R are fixed. So, rising T raises P.
In a system without rigid walls: V is not fixed. n and R are fixed. Rising T will lead to PV rising, not just to a straight P rising.
Given the huge n and V we’re talking about, that missile wouldn’t just need a nuclear reactor in its back end, it would need something out of Star Trek. The idea would make sense at small scale and in a closed box, not at the scales we’re talking here and with no walls or ceiling.
When I read about climate change, one of the aspects that is repeatedly mentioned is that the increased temperature of tropical seas will enable them to impart more energy to tropical air masses, resulting in more frequent and larger tropical depressions/storms/hurricanes.
The takeaway from all of that is this: storms exist because they have energy. Storms get worse when you give them more energy. How is the addition of more energy, via nuclear energy or any other means, expected to dissipate a storm, even one in its incipient stages?
This of course ignores the basic problem of scale, i.e. that a nuke (whether a nuclear-powered missile or a nuclear bomb) in a tropical storm system is comparable in scale to a mouse fart in stadium.
In casual parlance, a “nuclear missile” is indeed a missile that uses a conventional rocket or jet motor for thrust to deliver a nuclear bomb.
However, OP is referring to a nuclear-powered missile, i.e. one that uses a nuclear reactor as a power source for an air-breathing jet engine to produce propulsive thrust (such a missile could carry a nuclear or conventional payload). There were some research projects in the 1950s and 1960s, and a few nuclear-powered jet engines that produced thrust on the ground, but AFAIK there has never been a vehicle that flew using a nuclear-powered jet engine. Russia is reportedly working on a nuclear-powered cruise missile, and there are claims that it was involved in some sort of explosion and radiation incident earlier this month, but nobody is quite sure.
Let me make sure I understand this. The idea is that, in order to affect the consequences of a particularly dangerous pattern of atmospheric pressure variations, winds at varying altitudes and rainfall, it helps to use a nuclear missile in the heart of it?
Yeah, I’m not seeing how this is supposed to work.
The issue is warm, moist air. Heating the air makes it warmer. If anything, the extra heat causes extra moisture to be sucked up into the air from the ocean.
That’s how hand dryers work - some of the water on your hands is blown off (but still present in the room). Some gets absorbed by the skin. Some water evaporates into the air.
The end result is the opposite of drier air.
In this proposal, where exactly is the water in the air supposed to go? It doesn’t magically disappear from being heated.
Not sure where you are going with this but I have good thermodynamics background for modeling systems like this. The n is not constant since water vapor is being added from the water below and you have to use psychrometric charts. If you can give some more details, perhaps I can do the calcs.
I guess you maybe correct but would appreciate an order of magnitude calculations. How much energy in terms of MJ or MMBBTU are we talking about ?
Agreed. But we know that such a missile is technically feasible although the risks need to be worked out. For this thread, since it is a feasibility level evaluation, lets assume such a missile is available.
Well, I was merely using the most basic PVT relationship (mind you, one which too often gives results as good as those of more complicated methods) as a way to show the issue conceptually.
If you want exact calculations you need to begin by defining your terms.
Agreed and humankind has always been fighting weather / climate. The first line of defense is to cut CO2 emissions but we need to find other methods too.
I would change “storms exist because they have energy.” to “storms exist because they have organized energy.” The organization of the energy is important . The storm starts from tropical depression and keeps organizing the energy till it becomes a hurricane. Of course once it hits land, the organization is disrupted - the idea is to not let it organize at its inception.
The PVT relationship is not applicable to systems when you add water and evaporation to the system. Since you brought these equations into this thread, I believe there is somewhere we were going with this.
Look at this statement - "We are gonna compress explosive mixtures of gases and have a human with his family sit behind it while the system moves - What possibly could go wrong ?
Well that’s essentially what a CAR is !!
Before you get all defensive, I am seeking an answer at the feasibility level and fully understand that proper and extensive risk studies and mitigations need to be performed. I deal with millions of gallons of crude oil and billions of cubic feet of natural gas on a daily basis and am well aware of the risks involved.
The two proposals I’ve seen for hurricane mitigation involve denying them their source of energy: warm tropical seawater.
One scheme proposes an array of passive devices (Salter sinks). Each one is a large tube extending down from the warm surface of the ocean to its cooler depths. The tube is supported by a flotation ring that incorporates a ramp. Warm waves from the open ocean splash over the ramp to the area contained within the perimeter of the tube, pushing the warm water in the tube down to the depths. IOW, the waves make it skim warm water from the surface and drive it down to the depths, letting colder water well up to the surface in other areas, reducing the overall surface temps.
The other scheme proposes an array of active devices. Each one is a wind-turbine-powered pump that brings cold water from the depths to the surface, achieving basically the same result.
Given the scale required to achieve any meaningful results, the cost of something like this seems like it would probably be enormous. That is, until you consider the annual cost of hurricane-related damage.
The idea is to disrupt the organization of the storm. Warm air laden with moisture (water vapor is lighter than air) rises up and air from surrounding spaces rushes in to fill the void (lower pressure). This keeps on building like a feedback loop and becomes a tropical depression and subsequently a storm / hurricane.
Note that it needs a perfect set of conditions to setup this feedback loop. You can just also have normal clouds form.
The idea (as pointed out earlier) is to disrupt this feedback loop. I am not sure if the nuclear powered missile could provide enough energy to do that and hence the question. Looking only for order of magnitude calcs.