Spatial and Temporal Variability of Iodine in Aerosol

In this work, we describe the compilation and homogenization of an extensive data set aerosol iodine field observations in period between 1963 2018 discuss its spatial temporal dependences by comparison with CAM-Chem model simulations. A close to linear relationship soluble total is found (?80% soluble), which enables converting a large subset measurements into iodine. The resulting shows distinct latitudinal dependence, enhancement toward Northern Hemisphere (NH) tropics lower values poles. This behavior, has been predicted atmospheric models depend on global distribution main oceanic source (which turn depends reaction ozone aqueous iodide sea water-air interface, generating gas-phase I2 HOI), confirmed here for first time. Longitudinally, there some indication wave-one profile tropics, peaks Atlantic minimum Pacific. New from Antarctica show that south polar seasonal variation mirrors observed previously Arctic, two equinoctial maxima dominant maximum occurring spring. While no clear variability NH middle latitudes, different cycles tropical Long-term trends cannot be unambiguously established as result inhomogeneous time coverage analytical methods.