By Sid Perkins
Frost flowers, the delicate crystals that sometimes grow atop fresh sea ice, can be a substantial source of ozone-destroying bromine in the lower atmosphere near the poles, researchers suggest.
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Over tropical and temperate seas, salt spray from breaking waves provides most of the low-altitude atmospheric bromine. The origin of bromine over ice-bound oceans has remained a mystery, but several lines of evidence now point to frost flowers as culprits. These arrangements of needlelike ice crystals often grow on the new ice that forms rapidly in frigid conditions.