The Influence of Chemical and Mineral Compositions on the Parameterization of Immersion Freezing by Volcanic Ash Particles

Abstract

Volcanic ash (VA) from explosive eruptions contributes to aerosol loadings in the atmosphere. Aside from the negative impact of VA on air quality and aviation, these particles can alter the optical and microphysical properties of clouds by triggering ice formation, thereby influencing precipitation and climate. Depending on the volcano and eruption style, VA displays a wide range of different physical, chemical, and mineralogical properties. Here, we present a unique data set on the ice nucleation activity of 15 VA samples obtained from different volcanoes worldwide. The ice nucleation activities of these samples were studied in the Aerosol Interaction and Dynamics in the Atmosphere (AIDA) cloud simulation chamber as well as with the Ice Nucleation Spectrometer of the Karlsruhe Institute of Technology (INSEKT). All VA particles nucleated ice in the immersion freezing mode from 263 to 238K with ice nucleation active site (INAS) densities ranging from ∼105 to 1011 m−2, respectively. The variabilities observed among the VA samples, at any given temperature, range over 3.5 orders of magnitude. The ice‐nucleating abilities of VA samples correlate to varying degrees with their bulk pyroxene and plagioclase contents as a function of temperature. We combined our new data set with existing literature data to develop an improved ice nucleation parameterization for natural VA in the immersion freezing mode. This should be useful for modeling the impact of VA on clouds.

Ice‐Nucleating Particles That Impact Clouds and Climate: Observational and Modeling Research Needs

“…The choice of gas used for adsorption may represent a source of uncertainty in this approach as gases may differ in their interactions with particle surfaces. Ice nucleation studies have used nitrogen, water vapor and argon gas to quantify the specific surface area (Hiranuma et al, 2015;Umo et al, 2021). While Hiranuma et al (2015) found only minor differences between the specific surface areas of illite samples measured using nitrogen and water vapor, other aerosol types may exhibit different behavior due to differences in physicochemical surface properties and morphology.…”

“…The choice of gas used for adsorption may represent a source of uncertainty in this approach as gases may differ in their interactions with particle surfaces. Ice nucleation studies have used nitrogen, water vapor and argon gas to quantify the specific surface area (Hiranuma et al., 2015; Umo et al., 2021). While Hiranuma et al.…”

Ice Nucleation of Pharmaceutical and Synthetic Organic Emerging Contaminants: The Impact of Selected Environmental Conditions

“…Various inorganic and (bio)­organic materials in the environment may act as ice nucleating entities. , For instance, biological substances (e.g., Pseudomonas syringae) are highly efficient (∼ −2 to −4 °C), while nonbiological substances (e.g., Gypsum) tend to exhibit less efficient ice-nucleating capabilities (−16 to −21 °C). Volcanic ash particles have been shown to nucleate via the immersion freezing mode within a temperature range of −10 to −35 °C, and the ice nucleation active site densities range from 10 5 to 10 11 m –2 , respectively. , The soil dust achieves this ice activity at about −10 °C, because the ice nucleation efficiency (INE) starts to decrease at temperatures greater than −10 °C. Hill et al have reported that, at temperatures greater than −10 °C, most soils in arable lands achieve 10 6 per gram.…”

“…Volcanic ash particles have been shown to nucleate via the immersion freezing mode within a temperature range of −10 to −35 °C, and the ice nucleation active site densities range from 10 5 to 10 11 m −2 , respectively. 9,10 The soil dust achieves this ice activity at about −10 °C, because the ice nucleation efficiency (INE) starts to decrease at temperatures greater than −10 °C. Hill et al 11 have reported that, at temperatures greater than −10 °C, most soils in arable lands achieve 10 6 per gram.…”

Dispersion and Aging of Volcanic Aerosols After the La Soufrière Eruption in April 2021

“…The physicochemical properties and atmospheric lifetime of these aerosols modulate their interactions with clouds and radiation. For example, aged ash (coated with sulfate) differs from fresh ash (noncoated) not only in the optical properties (Muser et al., 2020) but also by affecting the ice and cloud nucleation (Maters et al., 2020; Umo et al., 2021). To improve our understanding of the impact volcanic eruptions can have on local and global weather, it is essential to constrain the processes that affect the properties and lifetime of volcanic aerosols (e.g., von Savigny et al., 2020).…”