Single Particle Mass Spectrometry of Soil and Dust Particles—Linking their Chemical Composition to Ice-Nucleation Activity
The in-situ identification of these particles by chemical characterization is the goal of the current work. Both, field and laboratory data from dusts and soil dusts of diverse global origin will be presented, linking their chemical composition and ice nucleation behavior. Emphasis is put on their identification in the atmosphere using “chemical fingerprints” from single particle mass spectrometry, and their ice-nucleation activity in the deposition and immersion mode.
Most of the presented data stem from in-situ measurements of Saharan dust and collected airborne particles that were subsequently re-dispersed for laboratory measurements. The measurements were performed (and the dust collected) during the CALIMA (Cloud Affecting particLes In Mineral dust from the sAhara) campaign which aimed at quantifying IN concentrations and onset conditions of ice nucleation in the Saharan Air Layer (SAL) close to the source. CALIMA was conducted at the Izaña Atmospheric Observatory, located west of the African shore on Tenerife, Canary Islands at 2400m a.s.l. for four weeks in August 2013 with a follow-up campaign in August 2014. The mass spectrometry results from CALIMA will be contrasted with those from soil dusts collected in Germany, Argentina, Mongolia, and Arizona Test Dust. For the CALIMA periods, the DREAM8 dust model extended with mineral fractions carried by dust was run to simulate meteorological and dust aerosol conditions for ice nucleation.
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