FY 1989

Long-range transport of giant mineral aerosol particles

Betzer, P.R., K.L. Carder, R.A. Duce, J.T. Merrill, N.W. Tindale, M. Uematsu, D.K. Costello, R.W. Young, R.A. Feely, J.A. Breland, R.E. Bernstein, and A.M. Greco

Nature, 336(6199), doi: 10.1038/336568a0, 568–571 (1988)

Several recent studies have shown that large quantities of mineral dust from eastern Asia are transported through the atmosphere to the North Pacific each spring. The paucity of information on mineral fluxes during individual dust events prompted a coordinated effort, Asian Dust Input to the Oceanic System (ADIOS), which simultaneously measured mineral fluxes in the atmosphere and upper water column during such an event. In March 1986 a major dust outbreak in China moved over the North Pacific Ocean and was detected downstream using changes in particle number, size and composition. Most striking was the presence of "giant" (>75-µm) silica minerals found in atmospheric as well as water-column samples at the ADIOS sampling site (26°N, 155°W). Their appearance more than 10,000 km from their source cannot be explained using currently acknowledged atmospheric transport mechanisms. Furthermore, the large wind-blown minerals that dominated our samples are extremely rare in the long-term sedimentary record in the North Pacific.