Please use this identifier to cite or link to this item:
Files in This Item:
File SizeFormat 
j.1600-0889.2011.00550.pdf3.7 MBAdobe PDFView/Open
Title: Electron microscopy of particles collected at Praia, Cape Verde, during the Saharan Mineral Dust Experiment: Particle chemistry, shape, mixing state and complex refractive index
Authors: Kandler, K.Lieke, K.Benker, N.Emmel, C.Küpper, M.Müller-Ebert, D.Ebert, M.Scheuvens, D.Schladitz, A.Schütz, L.Weinbruch, S.
Publishers Version:
Issue Date: 2017
Published in: Tellus B: Chemical and Physical Meteorology , Volume 63, Issue 4, Page 475-496
Publisher: Milton Park : Taylor & Francis
Abstract: A large field experiment of the Saharan Mineral Dust Experiment (SAMUM) was performed in Praia, Cape Verde, in January and February 2008. The aerosol at Praia is a superposition of mineral dust, sea-salt, sulphates and soot. Particles smaller than 500 nm are mainly mineral dust, mineral dust–sulphate mixtures, sulphates and soot–sulphate mixtures. Particles larger then 2.5μm consist of mineral dust, sea-salt and few mineral dust–sulphate mixtures. A transition range exists in between. The major internal mixtures are mineral dust–sulphate and soot–sulphate. Mineral dust–sea-salt mixtures occur occasionally, mineral dust–soot mixtures were not observed. The aspect ratio was 1.3–1.4 for dry particles smaller than 500 nm and 1.6–1.7 for larger ones. Parameterizations are given for dry and humid state. Although the real part of the refractive index showed low variation (1.55–1.58 at 532 nm), a multi-modal imaginary part was detected as function of particle size, reflecting the complex composition. Soot mainly influences the absorption for wavelengths longer than the haematite absorption edge, whereas for shorter wavelengths dust is dominating. The refractive index of the aerosol depends on the source region of the mineral dust and on the presence/absence of a marine component.
Keywords: aerosol; chemical composition; dust; electron microscopy; experimental study; mixing; particle size; refractive index; sea saltsoot
DDC: 550
License: CC BY 4.0 Unported
Link to License:
Appears in Collections:Geowissenschaften

This item is licensed under a Creative Commons License Creative Commons