On the role of iodine in ozone depletion

Ozone depletions in the lower stratosphere outside of polar regions are difficult to explain using only local chlorine and bromine chemistry. We speculate that iodine chemistry in combination with trends in anthropogenic chlorine and bromine may also be a factor in determining the widespread current depletion of lower stratospheric ozone. We also speculate on a related role for iodine in the sudden springtime surface ozone loss observed in the Arctic.