Complex refractive index and single scattering albedo of Icelandic dust in the shortwave part of the spectrum

Abstract m = n - i k) of Icelandic dust from five major emission hotspots were retrieved between 370–950 nm using online measurements of size distribution and spectral absorption (β abs β sca SSA (λ) estimated from the measured β abs β sca nm to 0.94–0.96 at 950 nm in Icelandic dust from the different hotspots, which falls within the range of mineral dust from northern Africa and eastern Asia. The spectral complex refractive index was retrieved by minimizing the differences between the measured β abs β sca n (λ)) was found to be 1.60–1.61 in the different samples and be independent of wavelength. The imaginary part (k (λ)) was almost constant with wavelength and was found to be around 0.004 at 370 nm and 0.002–0.003 at 950 nm. The estimated complex refractive index was close to the initial estimates based on the mineralogical composition, also suggesting that the high magnetite content observed in Icelandic dust may contribute to its high absorption capacity in the shortwave part of the spectrum. The k (λ)  values retrieved for Icelandic dust are at the upper end of the reported range for low-latitude dust (e.g., from the Sahel). Furthermore, Icelandic dust tends to be more absorbing towards the near-infrared. In Icelandic dust, k (λ) between 660–950 nm was 2–8 times higher than most of the dust samples sourced in northern Africa and eastern Asia. This suggests that Icelandic dust may have a stronger positive direct radiative forcing on climate that has not been accounted for in climate predictions.

Angaben zum Objekt

• Standort: Deutsche Nationalbibliothek Frankfurt am Main
• Umfang: Online-Ressource
• Sprache: Englisch

Verweise und Beziehungen

• Erschienen in: Complex refractive index and single scattering albedo of Icelandic dust in the shortwave part of the spectrum ; volume:23 ; number:14 ; year:2023 ; pages:7975-8000 ; extent:26 ; Atmospheric chemistry and physics ; 23, Heft 14 (2023), 7975-8000 (gesamt 26)

Beteiligte, Orts- und Zeitangaben

• Urheber: Baldo, Clarissa ; Formenti, Paola ; Di Biagio, Claudia ; Lu, Gongda ; Song, Congbo ; Cazaunau, Mathieu ; Pangui, Edouard ; Doussin, Jean-Francois ; Dagsson-Waldhauserova, Pavla ; Arnalds, Olafur ; Beddows, David ; MacKenzie, A. Robert ; Shi, Zongbo

Weitere Informationen

• DOI: 10.5194/acp-23-7975-2023
• URN: urn:nbn:de:101:1-2023072004183984174741
• Rechteinformation: Open Access; Der Zugriff auf das Objekt ist unbeschränkt möglich.
• Letzte Aktualisierung: 14.08.2025, 11:00 MESZ