a reply to: lostbook
Its not just water vapour that one needs to think about when considering the potential for lightning producing clouds to form in any given scenario.
Water vapour is only one material component. You also need impurities, tiny specks of this or that mineral or compound. As I am sure you are aware,
lightning is produced when static charges manifest in such a way as to create a situation where negative and positive ions are separated, until such
time as things reach a head, and one of these two becomes dominant enough to seek by natural attraction, the company of its counterparts, shall we
However, before that charge is built up, two things need to be present. The first is plenty of water vapour, and the second is impurities in that
cloud, particulates around which water ice can form. The process of water turning to ice, is much easier when impurities are present, because those
impurities create nucleation points, around which ice crystals form. Pure water alone is actually pretty resistant to becoming ice all on its own. In
fact, if you were to put a bottle of purified water in a freezer for two hours, and then carefully remove it, you would see that in fact the water had
not turned to ice. That is, until you slam the bottle down on a surface. It is impurities, and sudden impact forces, which create these nucleation
points with the greatest effect!
It is only when solid material, be it water ice with its attendant impurities, or indeed any significant volume of solid material, is forced to
collide and buffet its way around other particles capable of assembling a static charge by friction, that lightning is formed. You do not strictly
need water ice at all to produce lightning clouds. As some of you will be aware, the same thing happens if you just have a big cloud over a volcano!
The particles in the ash cloud, given the right circumstances, will create friction produced static charges just as readily, and depending on what the
composition of the ash cloud is, sometimes more readily!
Now, I am not saying that the video is wrong at all, but I am suggesting that the issue here is not a mere increase in water vapour, but an increase
in the presence of all the ingredients which lead to lightning.