"MET" napisal w wiadomosci
...
So estimate the "water content of the atmosphere" and post your answer.

Sorry, it's only now that I checked here again for an answer to my
initial question. (Since my question didn't get a reply for a while, I
actually lost hope to receive some help through this forum.)

@Szczepan: That's interesting. Unfortunately such measurements are not
(yet?) done or at least the results not yet published from the
different meteorological stations.

" Electric forces are responsible for whole liquid water content in clouds,
...." This is from: http://www.springerlink.com/content/e1846k71563j8527/

It is a new approach but the only to have good estimation.
Without electric factors such estimation is impossible.
S*
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