Ice nucleation activity of agricultural soil dust aerosols from Mongolia, Argentina, and Germany

Soil dust particles emitted from agricultural areas contain considerable mass fractions of organic material. Also, soil dust particles may act as carriers for potentially ice-active biological particles. In this work, we present ice nucleation experiments conducted in the Aerosol Interaction and Dyn...

Full description

Saved in:
Bibliographic Details
Main Authors: Steinke, Isabelle (Author) , Leisner, Thomas (Author)
Format: Article (Journal)
Language:English
Published: 17 Nov 2016
In: Journal of geophysical research. Atmospheres
Year: 2016, Volume: 121, Issue: 22, Pages: 13559-13576
ISSN:2169-8996
DOI:10.1002/2016JD025160
Online Access:Verlag, kostenfrei, Volltext: http://dx.doi.org/10.1002/2016JD025160
Get full text
Author Notes:I. Steinke, R. Funk, J. Busse, A. Iturri, S. Kirchen, M. Leue, O. Möhler, T. Schwartz, M. Schnaiter, B. Sierau, E. Toprak, R. Ullrich, A. Ulrich, C. Hoose, and T. Leisner
Description
Summary:Soil dust particles emitted from agricultural areas contain considerable mass fractions of organic material. Also, soil dust particles may act as carriers for potentially ice-active biological particles. In this work, we present ice nucleation experiments conducted in the Aerosol Interaction and Dynamics in the Atmosphere (AIDA) cloud chamber. We investigated the ice nucleation efficiency of four types of soil dust from different regions of the world. The results are expressed as ice nucleation active surface site (INAS) densities and presented for the immersion freezing and the deposition nucleation mode. For immersion freezing occurring at 254 K, samples from Argentina, China, and Germany show ice nucleation efficiencies which are by a factor of 10 higher than desert dusts. On average, the difference in ice nucleation efficiencies between agricultural and desert dusts becomes significantly smaller at temperatures below 247 K. In the deposition mode the soil dusts showed higher ice nucleation activity than Arizona Test Dust over a temperature range between 232 and 248 K and humidities RHice up to 125%. INAS densities varied between 109 and 1011 m−2 for these thermodynamic conditions. For one soil dust sample (Argentinian Soil), the effect of treatments with heat was investigated. Heat treatments (383 K) did not affect the ice nucleation efficiency observed at 249 K. This finding presumably excludes proteinaceous ice-nucleating entities as the only source of the increased ice nucleation efficiency.
Item Description:Gesehen am 16.03.2017
Physical Description:Online Resource
ISSN:2169-8996
DOI:10.1002/2016JD025160