Marine aerosol composition

Volpe C, Wahlen M, Spivack AJ (1998) Chlorine isotopic composition of marine aerosols Implications for the release of reactive chlorine and HCl cycling rates. Geophys Res Lett 25(20) 3831-3834 Volpe CM (1998) Stable Chlorine Isotope Variations in the Atmosphere. PhD Dissertation, University of California, San Diego, San Diego, California... 

Approximate times of polluted (P), continental (C), and marine (M) air masses are indicated based on synoptic weather maps and consistent with aerosol composition measurements. Times of impactor samples, taken in duplicate concurrently with the streaker, are indicated at the top as midpoints of alternating 10- and 12-h sampling periods. 

Howell, S. G., and B. J. Huebert, Determining Marine Aerosol Scattering Characteristics at Ambient Humidity from Size-Resolved Chemical Composition, J. Geophys. Res., 103, 1391-1404 (1998). 

Figure 1. Example of compositionally resolved bimodal and monomodal distributions of aerosols. The ordinate gives the percent of the species found in the given size fraction of the impactor. The mode near 0.3 xm is the accumulation mode , and that above 8 xm is the coarse mode The minimum of mass between 1 and 2 xm is typical the chlorine distribution is anomalous. Chlorine is in fact a coarse-mode marine aerosol that has lost its larger particles during transport from the ocean to Davis, California, a distance of roughly 100 km. (Reproduced with permission from reference 15. Copyright 1988.)...

The measurements will be extended for one year and we hope they will enhance the global data set of the chemical composition of the marine aerosol which is crucial for a complete understanding of his climatic relevance. 

In this study we have employed the simultaneous collection of atmospheric particles and gases followed by multielement analysis as an approach for the determination of source-receptor relationships. A number of particulate tracer elements have previously been linked to sources (e.g., V to identify oil-fired power plant emissions, Na for marine aerosols, and Pb for motor vehicle contribution). Receptor methods commonly used to assess the interregional impact of such emissions include chemical mass balances (CMBs) and factor analysis (FA), the latter often including wind trajectories. With CMBs, source-strengths are determined (1) from the relative concentrations of marker elements measured at emission sources. When enough sample analyses are available, correlation calculations from FA and knowledge of source-emission compositions may identify groups of species from a common source type and identify potential marker elements. The source composition patterns are not necessary as the elemental concentrations in each sample are normalized to the mean value of the element. Recently a hybrid receptor model was proposed by Lewis and Stevens (2) in which the dispersion, deposition, and conversion characteristics of sulfur species in power-plant emissions... 

Pierce, R.H., Henry, M.S., Blum, DC., Hamel, S.L., Kirkpatrick, B., Cheng, Y.S., Zhou, Y, Irvin, C.M., Naar, I, Weidner, A., Fleming, L.E., Backer, L.C., Baden, D.G. 2005. Brevetoxin composition in water and marine aerosol along a Florida beach Assessing potential human exposure to marine biotoxins. Harmful Algae 4, 965-972. 

The organic component is also present in marine aerosol. It is also characterized by a complicated chemical composition. Over remote oceanic regions the concentration of organic matter in the rough-disperse aerosol fraction can reach 2-4 mg/m [41], but in other cases it does not exceed 0.15-0.47 mg/m [18]. 

Volpe et al. (1998) analyzed the isotopic composition of chlorine in marine aerosol and found enrichment of Cl, i.e., the heavier chlorine isotope, in chlorine depleted aerosol, as expected, thereby providing further evidence for acid displacement in mid-size sea salt aerosols (mean aerodynamic diameter up to 2 p.m). In larger sea salt aerosol (mean aerodynamic diameter between... 

In the following discussion we shall use Table 7-13 as a reference in delineating the origins of the various inorganic components of continental and marine aerosols. In this discussion one must keep in mind that the aerosol represents a mixture of substances from several sources, and that any specific component may have more than one origin. The major sources in the natural atmosphere are sea salt, continental soils, and gas-to-particle conversion. To these must be added the various anthropogenic contributions. Comparison of aerosol and source compositions provides important clues with regard to the individual contributions. Below, we discuss first the anions and ammonium, then soluble and insoluble elements. 

Marty, J.C., Saliot, A., Buat-Menard, P., Chesselet, R. and Hunter, K.A., 1979. Relationship between the lipid compositions of marine aerosols, the sea-surface microlayer and subsurface water. J. Geophys. Res., 84 5707—5716. 

Sources contributing to the composition of inorganic aerosols near the ocearir-atmosphere interface are the oceans themselves, continental dust, volcanic ash, atmospheric production of particulates, and, to lesser extents, human activity and extraterrestrial inputs. Characteristic elements and elemental ratios can be used to determine some of these sources and detect ion fractionation at the sea-air interface. Rain water chemistry is not always simply related to that of the marine aerosol. 

Composition of Marine Aerosols tuith Respect to Geographic Area... 

Relative Chemical Composition of Marine Aerosol Salt... 

Several workers (39, 49, 50) have shown that the atmospheric concentration of salt derived from the ocean surface decreases rapidly to small values at an altitude of about 2 km. Are there also changes in chemical composition in the salt fraction of the marine aerosol with... 

The figure also includes land breeze data from two different altitudes, 90 and 1800 meters, which were obtained within 2 hours of each other from a circling aircraft. Again we see deviations from sea water ratios with increasing altitude for Cl/Na. The absolute values of the ratios containing F also show this change, but are different from marine aerosol ratios. In this case, however, the wind was from the land and the samples were collected about 150 miles from the U. S. east coast. The influence of a continental aerosol component did appear in the fluoride concentration (12). Similarly, changes in the relative chemical composition of marine aerosols with altitude have been reported by others for SO4/CI (2, 51) and Cl, Br, and I (44). 

In many instances the chemical composition of oceanic rain has been used to draw conclusions concerning the chemical composition of marine aerosols (3, 52, S3, 54). The first two entries in Table V emphasize the trends with respect to altitude for our data on rain samples collected in Hawaii. The 100-meter sample was collected near the coast, and the 1000-meter sample was obtained several miles inland in the Hawaiian mountains. The results for F/Cl, Cl/Na, and Na/F in the 100-meter sample agree with the results found for marine aerosol salt fractions given in Table II, and differ only slightly from those of sea water. 

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