Re: what is the mass of an average cumulus cloud, say , one cubic kilometer?

Mike, Average cumulus clouds contain around 0.5 grams of liquid water per cubic meter. Thus, the mass of the water in an average cumulus cloud is: M = 0.5 gm/m3 x 1000m x 1000m x 1000m = 500,000,000 gm = 500,000 kg which is around 1.1 million pounds, or 550 tons. A fully loaded 747 jet weighs in around 416 tons. Keeping all this water in the sky illustrates the power of convective elements in the atmosphere. (Of course, the total mass is distributed over a much larger area than that of the jet!) This calculation was done by Peggy Malone, a researcher at the National Center for Atmospheric Research. It was printed in USA TODAY's The Weather Book by Jack Williams.