Chemical Analysis of Aerosol Particles and of Gas Traces on the Island of Hawaii

Abstract

Aerosols of two different size ranges with radii between 0.08 < r < 0.8 μ (large particles) and 0.8 < r < 8 μ (giant particles) were analyzed for NH4+, Cl−, SO4− and NO3− Parallel with this, the concentration of corresponding gas traces, that is of NH3, chlorine components, SO2 and nitrogen dioxide was measured.
 The results show that the giant particles consisted almost entirely of sea spray. Their content of NO3− was small compared to the data from the East Coast of the United States (Round Hill, Massachusetts and Homestead, Florida).
 The Cl− content of the large particles was less than 1.5 % of that of the giant particles, confirming previous data which showed that the sea spray is almost completely restricted to particles larger than 0.8 μ radius. The large particles contained NH4 in amounts comparable with the other components, indicating the presence of other than sea spray nuclei in this size range. The NH4 is probably present in the form of (NH4)2SO4.
 Both particle sizes were completely missing in the raining orographic clouds.
 All gas components were found to be present and the concentrations did not fluctuate very much. They were washed out, to a small degree, if at all, by rain.