Do Microbes Make Snow?

Scientists discover microbes in snows sampled from different parts of the world--and show how

MICROBIAL SNOW: Pseudomonas syringae cellsencased within
an ice lattice show how microbes can make
snow--and potentially hitch a ride.

(SciAm.com) -- Microbes may be responsible for snow—and rain for that matter. They are certainly involved in much of the man-made snow that ski resorts use to cover for Mother Nature's winter lapses. Microorganisms, particularly bacteria, produce proteins in their cell walls that bind water—even if they are dead. In fact, they bind water in such an orderly fashion that water droplets freezing around a microbe almost mirror the natural lattice formation of ice. As a result, bacteria can help snow form at warmer temperatures than would otherwise be the case, which explains why some ski resorts add dead microbes to the mix in their snowmaking machines. And now scientists have discovered such biological precipitation catalysts in natural snows—in such far-flung locations as Montana and Antarctica. full story