if all the alleged atmospheric pollutants that are flying in the air today caused by coal and oil usage is replaced by water vapor, I have a nagging feeling that we just might be opening a pandoras box.
Overall, I can't see how artificially charging our atmosphere with water vapor could be advantageous to the planet. Look what happens to your bathroom walls, ceiling and mirror when you take a shower with the door closed........
What do you think rain is? Condensed water vapor. Some parts of the world would benefit from more rain. Oceans cover most of the globe and their evaporation in sunlight contributes more vapor to the atmosphere than man ever could. The atmosphere can absorb only so much moisture. When the air reaches saturation point, then the rest will condense and fall as rain.