HR: 1340h
AN: B13B-0223    [Abstracts]
TI: Atmospheric Dust Deposition as a Source of Nutrients and Trace Metals to the Northern Gulf of Aqaba
AU: * Street, J H
EM: jstreet@stanford.edu
AF: Stanford University, Department of Geological & Environmental Sciences, Stanford, Ca 94305 United States
AU: Paytan, A
EM: apaytan@pangea.stanford.edu
AF: Stanford University, Department of Geological & Environmental Sciences, Stanford, Ca 94305 United States
AU: Labiosa, R G
EM: jahajey@pangea.stanford.edu
AF: Stanford University, Department of Geophysics, Stanford, CA 94305 United States
AU: Golan, D
EM: doritgolan@hotmail.com
AF: Hebrew University, Interuniversity Institute of Marine Sciences, Eilat, 88103 Israel
AU: Post, A
EM: anton.post@huji.ac.il
AF: Hebrew University, Interuniversity Institute of Marine Sciences, Eilat, 88103 Israel
AU: Resing, J
EM: joseph.resing@noaa.gov
AF: NOAA Pacific Marine Environmental Laboratory, 7600 Sand Point Way N.E., Seattle, WA 98115 United States
AB: The deposition of atmospheric dust is a significant but poorly characterized component of nutrient and trace metal input to the euphotic zone of the ocean. Dust deposition is thought to be of particular importance in oligotrophic areas such as the Gulf of Aqaba where other nutrient and trace metal sources are scarce. Our goal is to characterize the magnitude and temporal variability of dust deposition, to evaluate the contribution of this source to the nutrient pool, and to determine the effect of this source on the pelagic ecosystem structure of the Gulf of Aqaba. We collected a multi-season time series of aerosol samples from a coastal station located at the Interuniversity Institute of Marine Sciences in Eilat, Israel, on the northwestern coast of the Gulf. Replicate samples of up to 70 m3 of air (24-hour integrated samples) were collected on 47-mm polycarbonate filters. We will present the results of this time series, including analyses of aerosol concentration and composition, and estimates of the deposition fluxes of N, P, Si, Fe and other trace elements. These data will be related to nutrient and trace metal distributions in the water column and to changes in productivity and ecosystem structure. The effect of aerosols on the growth of the dominant phytoplankton species in the Gulf will also be shown. Finally, a preliminary comparison between dust flux estimates using satellite data and the flux calculated from the aerosol filters will be presented.
DE: 4805 Biogeochemical cycles (1615)
DE: 4845 Nutrients and nutrient cycling
DE: 4243 Marginal and semienclosed seas
DE: 4801 Aerosols (0305)
DE: 0312 Air/sea constituent fluxes (3339, 4504)
SC: Biogeosciences [B]
MN: 2004 AGU Fall Meeting