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.
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.
When winds are calm and the humidity just above the fresh ice is high, a dense crop of frost flowers sprouts. The fragile str