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On the usage of classical nucleation theory in quantification of the impact of bacterial INP on weather and climate

Sahyoun, Maher LU ; Wex, Heike ; Gosewinkel, Ulrich ; Šantl-Temkiv, Tina ; Nielsen, Niels W. ; Finster, Kai ; Sørensen, Jens H. ; Stratmann, Frank and Korsholm, Ulrik S. (2016) In Atmospheric Environment 139. p.230-240
Abstract

Bacterial ice-nucleating particles (INP) are present in the atmosphere and efficient in heterogeneous ice-nucleation at temperatures up to -2 °C in mixed-phase clouds. However, due to their low emission rates, their climatic impact was considered insignificant in previous modeling studies. In view of uncertainties about the actual atmospheric emission rates and concentrations of bacterial INP, it is important to re-investigate the threshold fraction of cloud droplets containing bacterial INP for a pronounced effect on ice-nucleation, by using a suitable parameterization that describes the ice-nucleation process by bacterial INP properly. Therefore, we compared two heterogeneous ice-nucleation rate parameterizations, denoted CH08 and... (More)

Bacterial ice-nucleating particles (INP) are present in the atmosphere and efficient in heterogeneous ice-nucleation at temperatures up to -2 °C in mixed-phase clouds. However, due to their low emission rates, their climatic impact was considered insignificant in previous modeling studies. In view of uncertainties about the actual atmospheric emission rates and concentrations of bacterial INP, it is important to re-investigate the threshold fraction of cloud droplets containing bacterial INP for a pronounced effect on ice-nucleation, by using a suitable parameterization that describes the ice-nucleation process by bacterial INP properly. Therefore, we compared two heterogeneous ice-nucleation rate parameterizations, denoted CH08 and HOO10 herein, both of which are based on classical-nucleation-theory and measurements, and use similar equations, but different parameters, to an empirical parameterization, denoted HAR13 herein, which considers implicitly the number of bacterial INP. All parameterizations were used to calculate the ice-nucleation probability offline. HAR13 and HOO10 were implemented and tested in a one-dimensional version of a weather-forecast-model in two meteorological cases. Ice-nucleation-probabilities based on HAR13 and CH08 were similar, in spite of their different derivation, and were higher than those based on HOO10. This study shows the importance of the method of parameterization and of the input variable, number of bacterial INP, for accurately assessing their role in meteorological and climatic processes.

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author
publishing date
type
Contribution to journal
publication status
published
subject
keywords
Bacterial INP, Classical nucleation theory, Ice nucleation, Ice nucleation active proteins, Ice nucleation rate
in
Atmospheric Environment
volume
139
pages
11 pages
publisher
Elsevier
external identifiers
  • scopus:84971222345
ISSN
1352-2310
DOI
10.1016/j.atmosenv.2016.05.034
language
English
LU publication?
no
id
2ef7a660-04c8-47b9-a0d0-d962f21101d8
date added to LUP
2019-12-17 12:10:47
date last changed
2020-06-03 05:14:56
@article{2ef7a660-04c8-47b9-a0d0-d962f21101d8,
  abstract     = {<p>Bacterial ice-nucleating particles (INP) are present in the atmosphere and efficient in heterogeneous ice-nucleation at temperatures up to -2 °C in mixed-phase clouds. However, due to their low emission rates, their climatic impact was considered insignificant in previous modeling studies. In view of uncertainties about the actual atmospheric emission rates and concentrations of bacterial INP, it is important to re-investigate the threshold fraction of cloud droplets containing bacterial INP for a pronounced effect on ice-nucleation, by using a suitable parameterization that describes the ice-nucleation process by bacterial INP properly. Therefore, we compared two heterogeneous ice-nucleation rate parameterizations, denoted CH08 and HOO10 herein, both of which are based on classical-nucleation-theory and measurements, and use similar equations, but different parameters, to an empirical parameterization, denoted HAR13 herein, which considers implicitly the number of bacterial INP. All parameterizations were used to calculate the ice-nucleation probability offline. HAR13 and HOO10 were implemented and tested in a one-dimensional version of a weather-forecast-model in two meteorological cases. Ice-nucleation-probabilities based on HAR13 and CH08 were similar, in spite of their different derivation, and were higher than those based on HOO10. This study shows the importance of the method of parameterization and of the input variable, number of bacterial INP, for accurately assessing their role in meteorological and climatic processes.</p>},
  author       = {Sahyoun, Maher and Wex, Heike and Gosewinkel, Ulrich and Šantl-Temkiv, Tina and Nielsen, Niels W. and Finster, Kai and Sørensen, Jens H. and Stratmann, Frank and Korsholm, Ulrik S.},
  issn         = {1352-2310},
  language     = {eng},
  month        = {08},
  pages        = {230--240},
  publisher    = {Elsevier},
  series       = {Atmospheric Environment},
  title        = {On the usage of classical nucleation theory in quantification of the impact of bacterial INP on weather and climate},
  url          = {http://dx.doi.org/10.1016/j.atmosenv.2016.05.034},
  doi          = {10.1016/j.atmosenv.2016.05.034},
  volume       = {139},
  year         = {2016},
}