An Investigation of the North Atlantic Boundary Layer as Impacted by Air Pollution Originating from Eastern North America

Concentrations of methanesulfonate (MSA), nitrate (NO3-) and non-sea-salt sulfate (nssSO4-) were compared for five different air mass categories encountered during a 1993 NOAA cruise in the North Atlantic. NO3- and nssSO4- concentrations were highest during air masses originating from Europe and the...

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Bibliographic Details
Main Author: Zetwo, Michelle Patricia
Format: Other/Unknown Material
Language:unknown
Published: NSUWorks 1995
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Online Access:https://nsuworks.nova.edu/occ_stuetd/339
https://nsuworks.nova.edu/cgi/viewcontent.cgi?article=1056&context=occ_stuetd
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Summary:Concentrations of methanesulfonate (MSA), nitrate (NO3-) and non-sea-salt sulfate (nssSO4-) were compared for five different air mass categories encountered during a 1993 NOAA cruise in the North Atlantic. NO3- and nssSO4- concentrations were highest during air masses originating from Europe and the United States. MSA concentrations increased with increasing latitude. Dry deposition fluxes for the three analytes were compared with respect to particle size and air mass category. MSA had a mixed distribution with particle size, nssSO4- was found primarily on smaller particles (<1.1 μm radius), and NO3- was found primarily on larger particles (≥ 1. 1 μm radius). With respect to air mass category, the highest dry deposition flux for the three analytes was found during sampled air with European continental influence. Total dry deposition fluxes (all particle sizes) were compared with previous studies in the North Atlantic with respect to air mass category. The NO3- and nssSO4- fluxes in this study are lower than those reported in the mid 1980's in both clean marine air and air masses originating from the United States. These differences are probably due to interannual variation. Atmospheric nitrogen deposition from air masses originating in the U.S., found during this study, was considerably lower than the minimum nitrogen requirement for new primary production expressed in previous studies.