Anthropogenic influence on the distribution of tropospheric sulphate aerosol

摘要: HUMAN activities have increased global emissions of sulphur gases by about a factor three during the past century, leading to sulphate aerosol concentrations, mainly in Northern Hemisphere. Sulphate aerosols can affect climate directly, increasing backscattering solar radiation cloud-free air, and indirectly, providing additional cloud condensation nuclei1–4. Here we use transport–chemistry model estimate changes distribution tropospheric deposition non-seasalt that occurred since pre-industrial times. The increase concentration is small over Southern Hemisphere oceans, but reaches 100 northern Europe winter. Our calculations indicate, however, at most 6% anthropogenic available for formation new particles. This because one-half dioxide deposited on Earth's surface, remainder oxidized droplets so becomes associated with pre-existing Even so, rate particles may doubled