_version_ 1867167663564783616
author Stuut, Jan-Berend W
Zabel, Matthias
Ratmeyer, Volker
Helmke, Peer
Schefuß, Enno
Lavik, Gaute
Schneider, Ralph R
author_facet Stuut, Jan-Berend W
Zabel, Matthias
Ratmeyer, Volker
Helmke, Peer
Schefuß, Enno
Lavik, Gaute
Schneider, Ralph R
collection Datos científicos de ciencias marinas y ambientales
contents Atmospheric dust samples collected along a transect off the West African coast have been investigated for their physical (grain-size distribution), mineralogical, and chemical (major elements) composition. On the basis of these data the samples were grouped into sets of samples that most likely originated from the same source area. In addition, shipboard-collected atmospheric meteorological data, modeled 4-day back trajectories for each sampling day and location, and Total Ozone Mapping Spectrometer aerosol index data for the time period of dust collection (February-March 1998) were combined and used to reconstruct the sources of the groups of dust samples. On the basis of these data we were able to determine the provenance of the various dust samples. It appears that the bulk of the wind-blown sediments that are deposited in the proximal equatorial Atlantic Ocean are transported in the lower level (>~900 hPa) NE trade wind layer, which is a very dominant feature north of the Intertropical Convergence Zone (ITCZ). However, south of the surface expression of the ITCZ, down to 5°S, where surface winds are southwesterly, we still collected sediments that originated from the north and east, carried there by the NE trade wind layer, as well as by easterly winds from higher altitudes. The fact that the size of the wind-blown dust depends not only on the wind strength of the transporting agent but also on the distance to the source hampers a direct comparison of the dust's size distributions and measured wind strengths. However, a comparison between eolian dust and terrigenous sediments collected in three submarine sediment traps off the west coast of NW Africa shows that knowledge of the composition of eolian dust is a prerequisite for the interpretation of paleorecords obtained from sediment cores in the equatorial Atlantic.
format Dataset Open Access
id pangaea_https___doi_org_10_1594_PANGAEA_739147
institution PANGAEA
language en
publishDate 2005
publisher PANGAEA
record_format pangaea
spellingShingle Grain size distribution and bulk chemistry of eolian dust
Stuut, Jan-Berend W
Zabel, Matthias
Ratmeyer, Volker
Helmke, Peer
Schefuß, Enno
Lavik, Gaute
Schneider, Ralph R
AEOLD; Aeolian dust sample; Center for Marine Environmental Sciences; D1; D10; D11; D12; D13; D14; D15; D16; D17; D18; D19; D20; D21; D22; D23; D24; D25; D3; D4; D5; D6; D7; D8; D9; GeoB; Geosciences, University of Bremen; M41/1; M41/1_D1; M41/1_D10; M41/1_D11; M41/1_D12; M41/1_D13; M41/1_D14; M41/1_D15; M41/1_D16; M41/1_D17; M41/1_D18; M41/1_D19; M41/1_D2; M41/1_D20; M41/1_D21; M41/1_D22; M41/1_D23; M41/1_D24; M41/1_D25; M41/1_D3; M41/1_D4; M41/1_D5; M41/1_D6; M41/1_D7; M41/1_D8; M41/1_D9; MARUM; Meteor (1986)
Atmospheric dust samples collected along a transect off the West African coast have been investigated for their physical (grain-size distribution), mineralogical, and chemical (major elements) composition. On the basis of these data the samples were grouped into sets of samples that most likely originated from the same source area. In addition, shipboard-collected atmospheric meteorological data, modeled 4-day back trajectories for each sampling day and location, and Total Ozone Mapping Spectrometer aerosol index data for the time period of dust collection (February-March 1998) were combined and used to reconstruct the sources of the groups of dust samples. On the basis of these data we were able to determine the provenance of the various dust samples. It appears that the bulk of the wind-blown sediments that are deposited in the proximal equatorial Atlantic Ocean are transported in the lower level (>~900 hPa) NE trade wind layer, which is a very dominant feature north of the Intertropical Convergence Zone (ITCZ). However, south of the surface expression of the ITCZ, down to 5°S, where surface winds are southwesterly, we still collected sediments that originated from the north and east, carried there by the NE trade wind layer, as well as by easterly winds from higher altitudes. The fact that the size of the wind-blown dust depends not only on the wind strength of the transporting agent but also on the distance to the source hampers a direct comparison of the dust's size distributions and measured wind strengths. However, a comparison between eolian dust and terrigenous sediments collected in three submarine sediment traps off the west coast of NW Africa shows that knowledge of the composition of eolian dust is a prerequisite for the interpretation of paleorecords obtained from sediment cores in the equatorial Atlantic.
title Grain size distribution and bulk chemistry of eolian dust
topic AEOLD; Aeolian dust sample; Center for Marine Environmental Sciences; D1; D10; D11; D12; D13; D14; D15; D16; D17; D18; D19; D20; D21; D22; D23; D24; D25; D3; D4; D5; D6; D7; D8; D9; GeoB; Geosciences, University of Bremen; M41/1; M41/1_D1; M41/1_D10; M41/1_D11; M41/1_D12; M41/1_D13; M41/1_D14; M41/1_D15; M41/1_D16; M41/1_D17; M41/1_D18; M41/1_D19; M41/1_D2; M41/1_D20; M41/1_D21; M41/1_D22; M41/1_D23; M41/1_D24; M41/1_D25; M41/1_D3; M41/1_D4; M41/1_D5; M41/1_D6; M41/1_D7; M41/1_D8; M41/1_D9; MARUM; Meteor (1986)
url https://doi.org/10.1594/PANGAEA.739147