weather

Peter Lowenstein captured this rare rainbow pileus cloud, which was later picked up by NASA's Astronomy Picture of the Day.

Weather experts are gathering at the World Meteorological Organisation later this month to discuss ultra-short lasers as a promising tool for weather modulation and climate studies. Launching these lasers into the atmosphere could potentially control lightning and also assist in cloud production and rainfall. Researchers have begun testing the equipment outside, by firing short pulses of laser light at the sky.

Masked in the chaos, however, was an enormous plume of dust that the Russian meteor left behind in Earth's atmosphere. This cloud, which had hundreds of tons of material in it, was still lingering three months after the Feb. 15 explosion, a new study has found. Scientists created a video of the Russian meteor explosion's dust cloud to illustrate the phenomenon.

Via Laughing Squid:

Last Thursday, December 11, 2014, the Grand Canyon was filled with a sea of fog in a stunningly beautiful and rare weather event. The fog was trapped in the canyon by warm air above in what is known as a total cloud inversion.

Cool air offshore was very nearly at the saturation point, with a temperature near 20ºC and a dew point of about 19.5ºC. The air at this temperature can only hold a certain amount of water vapor, and how much it can hold depends heavily on the temperature. If you add more water into the air, a cloud will form, but you can also get a cloud to form by cooling the air. Drop the temperature, and it can no long hold as much water vapor, so some of it will condense out and a cloud will form."