caa a22 4500 475823257 CHVBK 20180406123824.0 cr unu---uuuuu 170329e20000701xx s 000 0 eng 10.1023/A:1006391626069 doi (NATIONALLICENCE)springer-10.1023/A:1006391626069 Numerical Investigation of the Influence of Mineral Dust on the Tropospheric Chemistry of East Asia [Elektronische Daten] [Mahesh Phadnis, Gregory Carmichael] An investigation of the influence of mineral dust ontrace gas cycles in the troposphere is carried out inthis study. A 3D regional scale atmospheric chemistrymodel (STEM-III) which includes aerosol processes isused for the numerical simulations for May 1987.Heterogeneous interactions between gaseous species(SO2, N2O5, HNO3, HO2andH2O2) and the dust particles are considered.Emissions of dust behind convective cold fronts aremodeled. The transport and distribution of mineraldust predicted from the model is compared withsatellite measurements (aerosol index from TOMS). Themodel is shown to capture the synoptic variability inthe observed aerosol index. Calculations show twomajor dust events in May 1987, during which thedust levels close to the source reach more than500 μg/m3. The transport of dust is mostlyrestricted towards the north, with the net continentaloutflow of ∼6 Tg for the entire month. Results showthat the presence of mineral aerosol can greatlyimpact sulfate and nitrate distributions. Averagedover the month of May, the presence of dust isestimated to increase particulate sulfate and nitratelevels in east Asia by ∼40%. Furthermore, the sulfateand nitrate on the dust particles are predicted to beassociated with the coarse mode (3-5 μm particlediameter), consistent with observations over Japan.The influence of mineral dust on the photochemicaloxidant cycle is also investigated. For the entiremonth, a5-10% decrease in boundary layer ozone ispredicted by the model closer to regions of higherdust levels. The ratio of nitric acid to NOx overmarine regions is reduced by a factor between 1 and 2in the boundary layer to more than 2 in the freetroposphere as a result of aerosol processes. Kluwer Academic Publishers, 2000 mineral dust nationallicence tropospheric chemistry nationallicence heterogeneous chemistry nationallicence East Asia nationallicence Phadnis Mahesh Center for Global and Regional Environmental Research and Department of Chemical and Biochemical Engineering, The University of Iowa, 52242, Iowa City, IA, U.S.A. aut Carmichael Gregory Center for Global and Regional Environmental Research and Department of Chemical and Biochemical Engineering, The University of Iowa, 52242, Iowa City, IA, U.S.A. aut Journal of Atmospheric Chemistry Kluwer Academic Publishers 36/3(2000-07-01), 285-323 0167-7764 36:3<285 2000 36 10874 https://doi.org/10.1023/A:1006391626069 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1023/A:1006391626069 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Phadnis Mahesh Center for Global and Regional Environmental Research and Department of Chemical and Biochemical Engineering, The University of Iowa, 52242, Iowa City, IA, U.S.A aut NATIONALLICENCE 700 1- Carmichael Gregory Center for Global and Regional Environmental Research and Department of Chemical and Biochemical Engineering, The University of Iowa, 52242, Iowa City, IA, U.S.A aut NATIONALLICENCE 773 0- Journal of Atmospheric Chemistry Kluwer Academic Publishers 36/3(2000-07-01), 285-323 0167-7764 36:3<285 2000 36 10874 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer