purplesofa: well, the water canopy is about 150 years old i think and i doubt the person who proposed it really studied its effects. The thing is, that its the mass of the atmospheare that creates preassure. So if you add water to the atmosfeare, no matter how you do it, it increase its mass. That increase the preasure. If you add, say, 100 meters of water, it increase the preasure to that 100 meters below surface. normal air is toxic at that depth - if you have seen a program about deep sea diving you will know you got to put helium and all kinds of weird stuff into the air to make it breathable, and even then its not healthy.
About it raining - true. god has two options: change the physical characteristics of water without killing humans who rely on those characteristics. thats basically a continious miracle. so why would god do that, just to have the air filled with water? it makes no sence unless it was gods plan all along to kill all humans which raise new questions.
The other option (that will work!) is to increase the temparature. by increasing i dont mean 4 or 10 degrees celcius, but hundreds of degrees (it depends on the amount of water). Again people will die.
Thats why people suggest why the water in the canoby orbits the earth like sattelites. That has problems of its own - see my previous post a page or two back - but raise new problems - water in orbit contains a tremendeous amount of energy. that energy has to go somewhere. basically it would sterelize the atmospheare if a body of water like just the mediteranean see fell down, again see the post for the calculation, its just highschool stuff. (E = gmh, T = E /(c*m), m is mass, h is height above earth, E is energy, T is temperature (in kelvin), c is specific heat capacity, g is gravity acceleration on surface).
IF there is an astronomer here he may calculate what effect the tidal drag of the moon would have on a water canopy. it put a limit on how dense it can be, and properly rule out any kind of rigid structure (which can be ruled out to begin with because it will be destroyd pretty quickly by meteors anyway).
the water canopy is a perfect example of a explanation that raise far greater problems than the original problem, its sort of like explaining where your lost slipper is by inventing a slipper-hiding dwarf that lives under your bed. IT does, however, delute the argument, and gives proponents something to talk about, which some seem to confuse as proof....