Mexican agricultural soil dust as a source of ice nucleating particles
-
Published:2022-05-19
Issue:10
Volume:22
Page:6435-6447
-
ISSN:1680-7324
-
Container-title:Atmospheric Chemistry and Physics
-
language:en
-
Short-container-title:Atmos. Chem. Phys.
Author:
Pereira Diana L., Gavilán Irma, Letechipía Consuelo, Raga Graciela B.ORCID, Puig Teresa Pi, Mugica-Álvarez Violeta, Alvarez-Ospina HarryORCID, Rosas Irma, Martinez Leticia, Salinas Eva, Quintana Erika T., Rosas Daniel, Ladino Luis A.ORCID
Abstract
Abstract. Agricultural soil erosion, both mechanical and eolic, may impact
cloud processes, as some aerosol particles are able to facilitate ice crystal formation. Given the large agricultural sector in Mexico, this study investigates the ice nucleating abilities of agricultural dust collected at different sites and generated in the laboratory. The immersion freezing mechanism of ice nucleation was simulated in the laboratory via the Universidad Nacional Autónoma de México (UNAM) microorifice
uniform deposit impactor (MOUDI) droplet freezing technique (DFT), i.e.,
UNAM-MOUDI-DFT. The results show that agricultural dust from the Mexican
territory promote ice formation in the temperature range from
−11.8 to −34.5 ∘C, with ice nucleating particle (INP) concentrations between 0.11 and 41.8 L−1. Furthermore, aerosol samples generated in the laboratory are more efficient than those collected in the field, with T50 values (i.e., the temperature at which 50 % of the droplets freeze) higher by more than 2.9 ∘C. Mineralogical analysis indicated a high concentration of feldspars, i.e., K-feldspar and plagioclase (>40 %), in most of the aerosol and soil samples, with K-feldspar significantly correlated with the T50 of particles with aerodynamic diameters between 1.8 and 3.2 µm. Similarly, the organic carbon (OC) was correlated with the ice nucleation efficiency of aerosol samples from 3.2 to 5.6 and from 1.0 to 1.8 µm. Finally, a decrease in INP efficiency after heating the samples at 300 ∘C for 2 h indicates that the organic matter from agricultural soils plays a predominant role in the ice nucleating abilities of this type of aerosol sample.
Funder
Consejo Nacional de Ciencia y Tecnología
Publisher
Copernicus GmbH
Subject
Atmospheric Science
Reference76 articles.
1. Alcaldía Milpa Alta: Milpa Alta en la actualidad,
https://www.milpa-alta.cdmx.gob.mx/ (last access: 26 August 2021), 2019 (in Spanish). 2. Atkinson, J. D., Murray, B. J., Woodhouse, M. T., Whale, T. F., Baustian, K.
J., Carslaw, K. S., Dobbie, S., O'Sullivan, D., and Malkin, T. L.: The
importance of feldspar for ice nucleation by mineral dust in mixed-phase
clouds, Nature, 498, 355–358, https://doi.org/10.1038/nature12278, 2013. 3. Ayuntamiento de Totolapan: TOTOLAPAN,
http://www.inafed.gob.mx/work/enciclopedia/EMM17morelos/municipios/17027a.html (last access: 26 August 2021), 2018 (in Spanish). 4. Baustian, K. J., Cziczo, D. J., Wise, M. E., Pratt, K. A., Kulkarni, G.,
Hallar, A. G., and Tolbert, M. A.: Importance of aerosol composition, mixing
state, and morphology for heterogeneous ice nucleation: A combined field and
laboratory approach, J. Geophys. Res., 117, D06217,
https://doi.org/10.1029/2011JD016784, 2012. 5. Birch, M. E. and Cary, R. A.: Elemental carbon-based method for monitoring
occupational exposures to particulate diesel exhaust, Aerosol Sci. Tech.,
25, 221–241, https://doi.org/10.1080/02786829608965393, 1996.
|
|