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E ffects of Climate change on atmospheric transport and deposition on mercury . Huanxin Zhang Ph.D Student in Environmental Engineering Michigan Technological University Advisor: Dr . Shiliang Wu Nov 14, 2013. Motivation. Mercury chemistry Wet deposition Air –sea exchange of mercury
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Effects of Climate change on atmospheric transport and deposition on mercury Huanxin Zhang Ph.D Student in Environmental Engineering Michigan Technological University Advisor: Dr . Shiliang Wu Nov 14, 2013
Motivation • Mercury chemistry • Wet deposition • Air –sea exchange of mercury • Land reemission(terrestrial system) (http://www.geo-tasks.org/geoss_portfolio/health_gmos.php)
How will climate change and climate driven changes in the chemical environment of the atmosphere affect these processes?
Methodology(sensitivity analysis) OH/O3 (2000) + meteorology (2000) OH/O3 (2000) + meteorology (2050) OH/O3 (2050) + meteorology (2000) OH/O3 (2050) + meteorology (2050) • GEOS-Chem Model: GISS GCM meteorology data fields for present day and future (GCAP) • OH/O3 data fields: archived from GCAP for year 2000 and 2005 as present day and future
Model Description Emission: Deposition: Anthropogenic emission: Hg(0), Hg(II), Hg(p) Ocean emission: air-sea exchange of Hg(0) Terrestrial system: land reemission, soil volatilization, evapotranspiration Biomass burning: Hg(0) Geogenic emission: Hg(0) Wet Deposition: Hg(II) & Hg(p) Dry Deposition: Hg(0), Hg(II) and Hg(p) Chemistry Hg(0): oxidation by OH (k=9x10-14 cm3 s-1) and O3 (k=3x10-20 cm3 s-1 ) Hg(II): aqueous phase photo-reduction ( Selin et al., 2008)
(Present OH/O3(2000)) Anthropogenic emission 3402 249 935 Hg(0) 3396 (2711) Hg(II) 294 (182) Hg(P) 80 (7) 892 497 628 1829 49 Dry Deposition Dry Deposition 260 Geogenic 614 4028 Dry Deposition Volatilization 734 300 Dry Deposition Land Reemission Evapotranspiration Wet Deposition 1637 Wet Deposition Biomass burning Ocean emission (All inventories are in Mg and rates are in Mg yr-1. Tropospheric inventories are given in parentheses)
(Present OH/O3(2050)) Anthropogenic emission 3402 249 935 Hg(0) 3415 (2714) Hg(II) 280 (179) Hg(P) 75 (7) 895 497 641 1847 49 Dry Deposition Dry Deposition 256 Geogenic 619 3965 Dry Deposition Volatilization 716 224 Dry Deposition Land Reemission Evapotranspiration Wet Deposition 1647 Wet Deposition Biomass burning Ocean emission (All inventories are in Mg and rates are in Mg yr-1. Tropospheric inventories are given in parentheses)
(Future OH/O3(2000)) Anthropogenic emission 3402 249 935 Hg(0) 3467 (2757) Hg(II) 294 (184) Hg(P) 80 (7) 915 497 628 1790 49 Dry Deposition Dry Deposition 256 Geogenic 614 4030 Dry Deposition Volatilization 723 300 Dry Deposition Land Reemission Evapotranspiration Wet Deposition 1624 Wet Deposition Biomass burning Ocean emission (All inventories are in Mg and rates are in Mg yr-1. Tropospheric inventories are given in parentheses)
(Future OH/O3(2050)) Anthropogenic emission 3402 249 935 Hg(0) 3467 (2757) Hg(II) 294 (184) Hg(P) 80 (7) 917 497 641 1806 49 Dry Deposition Dry Deposition 256 Geogenic 619 3962 Dry Deposition Volatilization 709 224 Dry Deposition Land Reemission Evapotranspiration Wet Deposition 1636 Wet Deposition Biomass burning Ocean emission (All inventories are in Mg and rates are in Mg yr-1. Tropospheric inventories are given in parentheses)
Future Work • Fix the imbalance between global mercury emission and deposition • Add conversion between Hg(0) and Hg(II) in the atmosphere • Diagnose the deposition to the land and ocean respectively
Change in surface Hg(0) concentration due to climate change in OH field Change in surface Hg(0) concentration due to climate change
Change in surface Hg(II) wet deposition due to change in OH/O3 Change in surface Hg(II) wet deposition due to climate change