HR: 1330h
AN: A42A-0739    [PDF]
TI: Partitioning of Nitric Acid to Nitrate by NaCl and CaCO$_{3}$ and Its Effect on Nitrogen Deposition
AU: * Evans, M C
EM: meevans@hsc.usf.edu
AF: University of South Florida, 13201 Bruce B. Downs Blvd. MDC 56, Tampa, FL 33612 United States
AU: Campbell, S W
EM: campbell@eng.usf.edu
AF: University of South Florida, 4202 E. Fowler Ave. ENB 118, Tampa, FL 33620 United States
AU: Poor, N D
EM: npoor@hsc.usf.edu
AF: University of South Florida, 13201 Bruce B. Downs Blvd. MDC 56, Tampa, FL 33612 United States
AB: Nitrogen oxides produced by combustion in automobile engines, power plant boilers, and industrial processes are transformed to nitric acid in the atmosphere. This nitric acid then deposits to land or water and may be a significant nitrogen input to sensitive coastal estuaries. The sodium chloride from sea salt spray and calcium carbonate from mineral dust react in the atmosphere with nitric acid to form sodium nitrate or calcium nitrate, respectively. The nitrate particle deposition velocity can be substantially lower than that of nitric acid, which may lower the atmospheric nitrogen deposition rate near the urban sources of nitrogen oxides but raise the deposition rate over the open water. The relative effects of different ambient air concentrations of sodium chloride and calcium carbonate on nitrogen atmospheric deposition rates were examined by using the EQUISOLVII model to estimate the partitioning of nitric acid to nitrate combined with the NOAA buoy model and Williams model to calculate the gas and aerosol deposition velocities.
DE: 0305 Aerosols and particles (0345, 4801)
DE: 0335 Ion chemistry of the atmosphere (2419, 2427)
DE: 0345 Pollution--urban and regional (0305)
SC: Atmospheric Sciences [A]
MN: 2003 Fall Meeting