Bermuda chemical composition

Chemical composition data for CPM and FPM for a variety of locations are summarized in Table 5. These data illustrate several important points. First, the distributions of the PM q between CPM and FPM vary from about 0.4 to 0.7. Second, the ratio of PM q to TSP varies from 0.58 to 0.79. In general, both this ratio and the ratio of FPM to PM q tend to be higher at mral sites, but Bermuda, because of the large influence of sea salt in the CPM, is an exception. Sulfate (SO ), carbon (as organic carbon, OC, and elemental carbon, EC), and nitrate (NO3 ) compounds generally account for 70—80% of the FPM. In the eastern United States, compounds are the dominant species, although very Httie is emitted directiy into the atmosphere. Thus... 

Beers, J.R., Studies on the chemical composition of the major zooplankton groups in the Sargasso Sea off Bermuda, Limnol. Oceanogr., 11, 520, 1966. 

The use of the site on Bermuda to collect precipitation that is chemically representative of the marine environment assumes that Bermuda itself does not influence the amount or composition of the precipitation. Because the island is low and narrow, its configuration did not influence the amount (5.) although it could affect the composition. In analyses of precipitation from two sites on Bermuda, the sea-salt and excess Ca2+ components of precipitation were found to increase as a result of turbulence at the sea/land and air/land interfaces, respectively (Galloway, J. N. Tokos, J. J. Whelpdale, D. M Knap, A. H., University of Virginia, Charlottesville, unpublished data). Also for samples taken from precipitation-collection sites downwind of the island, concentrations of excess SO and H+ were slightly increased by local sources. However, the impact of the island on the total excess SO and H+ concentrations was small relative to the off-island sources. 

WATOX also used ships as platforms to collect precipitation for chemical analyses. To test the impact on the precipitation composition of the fossil fuels used by the ships for propulsion, Galloway, Knap, and Church (6) had precipitation samples collected on the windward and leeward bridge wings of two ships sailing between New York and Bermuda. They report that the samples from the windward bridge wings are unaffected by the ship and are thus representative of marine precipitation and appropriate for use in analyses of the major chemical constituents sought. 

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