Dust mass deposition fluxes to the tropical northeast Atlantic Ocean
نویسنده
چکیده
This discussion paper is/has been under review for the journal Atmospheric Chemistry and Physics (ACP). Please refer to the corresponding final paper in ACP if available. Abstract The aim of this study is to determine the mass deposition flux of mineral dust to the tropical northeast Atlantic Ocean at the Cape Verde Atmospheric Observatory (CVAO) on the island Sao Vicente for January 2009. Five different methods were applied to estimate the deposition flux, using different meteorological and microphysical measure-5 ments, remote sensing, and regional dust transport simulations. The set of observations comprises micrometeorological measurements with an ultra-sonic anemometer and profile measurements using 2-D anemometers at two different heights, and mi-crophysical measurements of the size-resolved mass concentrations of mineral dust. In addition, the total mass concentration of mineral dust was derived from absorption 10 photometer observations and passive sampling. The regional dust model COSMO-MUSCAT was used for simulations of dust emission and transport, including dry and wet deposition processes. The four observation-based methods yield a monthly average deposition flux of mineral dust of 12–29 ng m −2 s −1. The simulation results come close to the upper range of the measurements with an average value of 47 ng m −2 s −1. It is shown, that the mass deposition flux of mineral dust obtained by the combination of micrometeorological (ultra-sonic anemometer) and microphysical measurements (particle mass size distribution of mineral dust) is within 5 % to modeled mass deposition fluxes when the mineral dust is relatively homogenously distributed over the investigated area.
منابع مشابه
Mass deposition fluxes of Saharan mineral dust to the tropical northeast Atlantic Ocean: an intercomparison of methods
Mass deposition fluxes of mineral dust to the tropical northeast Atlantic Ocean were determined within this study. In the framework of SOPRAN (Surface Ocean Processes in the Anthropocene), the interaction between the atmosphere and the ocean in terms of material exchange were investigated at the Cape Verde atmospheric observatory (CVAO) on the island Sao Vicente for January 2009. Five different...
متن کاملAtmospheric and oceanic dust fluxes in the northeastern tropical Atlantic Ocean: how close a coupling?
Atmospheric inputs to the ocean of dust originating from Africa are compared with downward dust flux in the oceanic water column. Atmospheric fluxes were estimated using remote-sensing-derived dust optical thickness and parameters from a transport/deposition model (TM2z). Oceanic fluxes were measured directly over/in two regions of contrasting primary productivity of the northeastern tropical A...
متن کاملAerosol time-series measurements over the tropical Northeast Atlantic Ocean: Dust sources, elemental composition and mineralogy
متن کامل
Influence of atmospheric circulation patterns on dust transport during Harmattan Period in West Africa
This study has used TOMS AI as well as the reanalysis dataset of thirty-four years (1979-2012) to investigate the influence of atmospheric circulation on dust transport during the Harmattan period in West Africa, using Aerosol Index (AI) data, obtained from various satellite sensors. Changes in Inter-Tropical Discontinuity (ITD), Sea Surface Temperature (SST) over the Gulf of Guinea, and North ...
متن کاملBiological response to millennial variability of dust and nutrient supply in the Subantarctic South Atlantic Ocean.
Fluxes of lithogenic material and fluxes of three palaeo-productivity proxies (organic carbon, biogenic opal and alkenones) over the past 100,000 years were determined using the (230)Th-normalization method in three sediment cores from the Subantarctic South Atlantic Ocean. Features in the lithogenic flux record of each core correspond to similar features in the record of dust deposition in the...
متن کامل