Elemental composition and time series analysis of concentrations of aerosols collected on Hawaii above and below the inversion layer in spring and summer 1979 have provided insight into the sources, transport processes, and chemistry of different aerosol components present in this marine atmosphere. Aerosols were sampled by 3.7-hour time resolution streakers (Nuclepore filter strip and sliding suction orifice) and analyzed by particle-induced X ray emission (PIXE) for elements heavier than Mg. At Mauna Loa Observatory (3.4 km altitude) April 23 to May 6, 1979, during a haze period caused by east Asian desert dust storms, a continental dust component of up to 20 (mu)g m('-3) or more and an aerosol sulfate component, sometimes in excess of 8 (mu)g m('-3), were measured. High coherency at long periodicities between the two components suggests pollution from China and Japan as the sulfur source. Since a 21-hour, not 24-hour, variation was prominent, an initially diurnal periodicity in upward transport foreshortened during transport across the Pacific, e.g. by wind speed convergence, is suggested. Continental dust was also found to be abundant, at 1-2 (mu)g m('-3) median concentration, in spring 1979 at 1.2 km (Hawaiian Volcano Observatory), but was essentially absent in the summer. Over both seasons, the local basaltic aerosol biweekly medians varied 100-fold, 0.2-18 (mu)g m('-3), a variation associated with rainfall. Compositional differences between the continental dust at HVO and MLO may indicate the presence of two distinct desert dust plumes over Hawaii. An additional component of volcanic emissions from Kilauea, containing aerosol P, Cl, and S, was also observed at HVO. The presence of all three elements was sporadic, especially for P, and all were found with concentrations of up to 1 (mu)g m('-3). However, P and Cl were almost never detected simultaneously, suggesting a volatility release of HCl from aerosol particles by reaction with strong acid associated with P. If such strong acid is due to H(,2)SO(,4), it is not well predicted by S, which may include other sulfates or sulfur. / Source: Dissertation Abstracts International, Volume: 43-03, Section: B, page: 0663. / Thesis (Ph.D.)--The Florida State University, 1982.
Identifer | oai:union.ndltd.org:fsu.edu/oai:fsu.digital.flvc.org:fsu_74801 |
Creators | Darzi, Michael |
Source Sets | Florida State University |
Language | English, English |
Detected Language | English |
Type | Text |
Format | 204 p. |
Rights | On campus use only. |
Relation | Dissertation Abstracts International |
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