Rethinking Rain

摘要

See that pristine, puffy cloud floating on the horizon? It's full of bacteria that might contribute to the formation of rain and snow, according to research by Brent Christner, a microbiologist and ice-core specialist at Louisiana State University. Not only could his work compel meteorologists to reconsider the science of precipitation, it could even give people the power to make it storm on demand.rnChristner began his research four years ago, while investigating how Pseudomonas syringae, a bacterium that helps make frost form on plants, moves around the globe. The leading theory was that the critters traveled on windblown seeds. But when Christner analyzed snow samples from 19 different sites, including subzero regions of Antarctica and Canada where seeds don't blow around.