Research article 26 Feb 2019
Research article | 26 Feb 2019
Revisiting the differential freezing nucleus spectra derived from drop-freezing experiments: methods of calculation, applications, and confidence limits
Gabor Vali
Related authors
Gabor Vali
Atmos. Chem. Phys., 21, 2551–2568, https://doi.org/10.5194/acp-21-2551-2021, https://doi.org/10.5194/acp-21-2551-2021, 2021
Short summary
Short summary
The freezing of water drops in clouds is a prime example for the role of ice-nucleating particles (INPs). Mercuric iodide particles and a few other substances can be conditioned to become very effective INPs after previous ice formation and moderate heating to melt temperatures, opening a new pathway to ice formation in the atmosphere and in other systems like tissue preservation, artificial snow making, and more.
G. Vali, P. J. DeMott, O. Möhler, and T. F. Whale
Atmos. Chem. Phys., 15, 10263–10270, https://doi.org/10.5194/acp-15-10263-2015, https://doi.org/10.5194/acp-15-10263-2015, 2015
Short summary
Short summary
Clarification is needed in the terminology used to discuss ice nucleation in the literature. Conflicting interpretations coupled with uncertainties about the details of the processes have led to difficulties in the clear communication of results and ideas. This paper contains a proposal for future usage. This proposed terminology was arrived at as a result of a year-long exchange of suggestions by a number of scientists.
G. Vali and J. R. Snider
Atmos. Chem. Phys., 15, 2071–2079, https://doi.org/10.5194/acp-15-2071-2015, https://doi.org/10.5194/acp-15-2071-2015, 2015
G. Vali
Atmos. Chem. Phys., 14, 5271–5294, https://doi.org/10.5194/acp-14-5271-2014, https://doi.org/10.5194/acp-14-5271-2014, 2014
Gabor Vali
Atmos. Chem. Phys., 21, 2551–2568, https://doi.org/10.5194/acp-21-2551-2021, https://doi.org/10.5194/acp-21-2551-2021, 2021
Short summary
Short summary
The freezing of water drops in clouds is a prime example for the role of ice-nucleating particles (INPs). Mercuric iodide particles and a few other substances can be conditioned to become very effective INPs after previous ice formation and moderate heating to melt temperatures, opening a new pathway to ice formation in the atmosphere and in other systems like tissue preservation, artificial snow making, and more.
G. Vali, P. J. DeMott, O. Möhler, and T. F. Whale
Atmos. Chem. Phys., 15, 10263–10270, https://doi.org/10.5194/acp-15-10263-2015, https://doi.org/10.5194/acp-15-10263-2015, 2015
Short summary
Short summary
Clarification is needed in the terminology used to discuss ice nucleation in the literature. Conflicting interpretations coupled with uncertainties about the details of the processes have led to difficulties in the clear communication of results and ideas. This paper contains a proposal for future usage. This proposed terminology was arrived at as a result of a year-long exchange of suggestions by a number of scientists.
G. Vali and J. R. Snider
Atmos. Chem. Phys., 15, 2071–2079, https://doi.org/10.5194/acp-15-2071-2015, https://doi.org/10.5194/acp-15-2071-2015, 2015
G. Vali
Atmos. Chem. Phys., 14, 5271–5294, https://doi.org/10.5194/acp-14-5271-2014, https://doi.org/10.5194/acp-14-5271-2014, 2014
Related subject area
Subject: Aerosols | Technique: Laboratory Measurement | Topic: Data Processing and Information Retrieval
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Short summary
The abundance of freezing nuclei in water samples is routinely determined by experiments involving the cooling of sample drops and observing the temperatures at which the drops freeze. This is used for characterizing the nucleating abilities of materials in laboratory preparations or to determine the numbers of nucleating particles in rain, snow, river water or other natural waters. The evaluation of drop-freezing experiments in terms of differential nucleus spectra is advocated in the paper.
The abundance of freezing nuclei in water samples is routinely determined by experiments...