HR: 1340h
AN: A13A-0878    [Abstracts]
TI: Does Ammonia Accelerate New Particle Formation in the Marine Sulfur Cycle?
AU: * Lucas, D D
EM: ddlucas@tamu.edu
AF: Texas A&M University, Department of Atmospheric Sciences, College Station, TX 77843,
AB: Gaseous ammonia (NH₃) enhances aerosol nucleation and is present in the remote marine atmosphere. These factors suggest that NH₃ may accelerate new particle formation in the marine sulfur cycle that connects dimethyl sulfide (DMS) to cloud condensation nuclei. Besides aerosol nucleation, NH₃ also couples to the marine sulfur cycle in other ways, some of which act to suppress new particle formation. Using an atmospheric transport model with coupled sulfur and ammonia chemistry, the role of NH₃ in modulating new particle production in the marine sulfur cycle is tested. The following three effects are investigated: (1) enhancements to aerosol nucleation by NH₃; (2) changes to cloudwater pH which reduce nucleation precursors; and (3) modifications to the sea air fluxes of DMS and NH₃ by a marine bacteria ( Nitrosomonas oceanus).
DE: 0305 Aerosols and particles (0345, 4801, 4906)
DE: 0469 Nitrogen cycling
DE: 0488 Sulfur cycling
DE: 4801 Aerosols (0305, 4906)
SC: Atmospheric Sciences [A]
MN: 2007 Fall Meeting