Facts for Those with Heads in the Clouds
Sunday
Clouds are made of water evaporated from the Earth’s surface suspended in the air as droplets or tiny ice crystals, since the water has condensed (or also frozen) at higher altitudes where it is cooler. These droplets form by water first adhering to a particle such as dust, dirt, smoke, pollen, or sea salt, which are known as “nuclei.”
Monday
These nuclei can be put in the sky artificially to encourage precipitation by a process called “cloud seeding.” Silver iodide, which has a structure similar to ice, is typically used, and tiny ice crystals tend to form around this seeding particle. According to several studies, this has increased snowpack in mountainous areas by 10-15%.
Tuesday
Fog is really just a cloud that’s very near the ground and, by definition, reduces visibility to one kilometer or less.
Wednesday
There are four main types of clouds, and in addition to being different shapes, they’re typically found at different heights. They are cirrus (thin and wispy), cumulus (puffy), stratus (layered like a blanket), and nimbus (rain clouds).
Thursday
Fluffy floating clouds seem nearly weightless, but they are not, since water is heavy. A modest-sized cumulus cloud measuring one km on each side, for example, weighs about 551 tons, or about the weight of 42 school buses.
Friday
Other planets have clouds, but they’re scary. These clouds can be made of, among other things, ammonia, sand, and metal.
Saturday
Concert organizers once paid $55,000 to make the rain clouds go away before a 2004 Paul McCartney concert in St. Petersburg Palace Square. Three jets sprayed the heavy clouds with frozen carbon dioxide, which theoretically should make the clouds disperse, though this is difficult to prove. In any event, the clouds disappeared, and Sir Paul played “Good Day Sunshine” under a clear sky.