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Elucidating Ice Nucleation Mechanisms Relevant to the Atmosphere: Is deposition nucleation really immersion freezing in pores?

Applicant Kanji Zaminhussein
Number 156581
Funding scheme Project funding (Div. I-III)
Research institution Institut für Atmosphäre und Klima ETH Zürich
Institution of higher education ETH Zurich - ETHZ
Main discipline Inorganic Chemistry
Start/End 01.02.2015 - 31.03.2019
Approved amount 453'848.00
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All Disciplines (2)

Discipline
Inorganic Chemistry
Climatology. Atmospherical Chemistry, Aeronomy

Keywords (3)

Pore Immersion Freezing; Deposition nucleation; mesoporous Silica

Lay Summary (German)

Lead
Die Wolkenbildung ist ein wichtiger Prozess in der Atmosphäre, den man noch nicht sehr gut versteht. Man weiss, dass es Aerosolpartikel braucht, damit sich Wolkentröpfchen oder Eiskristalle in der Atmosphäre bilden. Eine offene Frage ist, wie Aerosolpartikel beschaffen sein müssen, damit sich an ihnen Eis bilden kann.
Lay summary
Wolken bestehen aus flüssigen Wassertröpfchen, Eiskristallen oder einer Mischung von Eis und Wassertröpfchen. Es gibt verschiedene Mechanismen, wie Eiskristalle in Wolken entstehen können. Zum einen kann sich Eis spontan in flüssigem Wasser bilden. Damit diese homogene Eisnukleation in Wolkentröpfchen stattfindet, müssen jedoch die Temperaturen sehr  tief sein.  Wenn Wolkentröpfchen feste Aerosolpartikel enthalten können diese bereits bei höheren Temperaturen zum Gefrieren der Tröpfchen führen. In diesem Fall spricht man von heterogener Eisnukleation. In der oberen Troposphäre bilden sich Eiskristalle auch direkt an Aerosolpartikeln. Das geschieht bei relativen Feuchten, die zu tief sind, damit sich flüssige Wassertröpfchen bilden könnten.  Bisher hat man immer angenommen, dass sich die Eisphase bildet, indem sich Wassedampf an den Partikeln abscheidet. Dieser Prozess wird Depositionsnukleation genannt. Viele feste Aerosolpartikel enthalten jedoch Poren, die Wasser aufnehmen auch wenn die relative Feuchte kleiner als 100 % ist. Je nach Dicke der Poren, kann das Wasser in den Poren gefrieren. In diesem Projekt soll jetzt untersucht werden, wie dick die Poren sein müssen, damit in ihnen Wasser gefriert und ob eine Abhängigkeit von der Beschaffenheit der Oberfläche der Poren besteht. Dazu sollen Partikel mit einheitlicher Porengrösse durch eine Eiskammer geleitet werden, in der sich die Temperatur und die relative Feuchte regulieren lassen. So kann man feststellen, unter welchen Bedingungen sich Eis in den Poren bildet. Wenn sich in der Kammer Eiskristalle gebildet haben,  können diese mit einem Detektor von den Aerosolpartikeln unterschieden werden. Falls sich bereits in schmalen Poren Eis bildet, hätte man einen zusätzlichen Nukleationsprozess, der wichtig sein könnte für die Bildung von Eiswolken.
Direct link to Lay Summary Last update: 07.01.2015

Responsible applicant and co-applicants

Employees

Project partner

Publications

Publication
Pore condensation and freezing is responsible for ice formation below water saturation for porous particles
David Robert O., Marcolli Claudia, Fahrni Jonas, Qiu Yuqing, Perez Sirkin Yamila A., Molinero Valeria, Mahrt Fabian, Brühwiler Dominik, Lohmann Ulrike, Kanji Zamin A. (2019), Pore condensation and freezing is responsible for ice formation below water saturation for porous particles, in Proceedings of the National Academy of Sciences, 201813647-201813647.
A laboratory investigation of the ice nucleation efficiency of three types of mineral and soil dust
Paramonov Mikhail, David Robert O., Kretzschmar Ruben, Kanji Zamin A. (2018), A laboratory investigation of the ice nucleation efficiency of three types of mineral and soil dust, in Atmospheric Chemistry and Physics, 18(22), 16515-16536.
Ice nucleation abilities of soot particles determined with the Horizontal Ice Nucleation Chamber
Mahrt Fabian, Marcolli Claudia, David Robert O., Grönquist Philippe, Barthazy Meier Eszter J., Lohmann Ulrike, Kanji Zamin A. (2018), Ice nucleation abilities of soot particles determined with the Horizontal Ice Nucleation Chamber, in Atmospheric Chemistry and Physics, 18(18), 13363-13392.
An Investigation of Ice Nucleation: From Pores to the Outdoors
DavidRobert (2018), An Investigation of Ice Nucleation: From Pores to the Outdoors, ETH , Zurich.
Uncertainty in counting ice nucleating particles with continuous flow diffusion chambers
Garimella Sarvesh, Rothenberg Daniel A., Wolf Martin J., David Robert O., Kanji Zamin A., Wang Chien, Rösch Michael, Cziczo Daniel J. (2017), Uncertainty in counting ice nucleating particles with continuous flow diffusion chambers, in Atmospheric Chemistry and Physics, 17(17), 10855-10864.

Datasets

Pore condensation and freezing is responsible for ice formation below water saturation for porous particles

Author David, Robert; Marcolli, Claudia; Fahrni, Jonas; Qiu, Yuqinq; Perez Sirkin, Yamila; Molinero, Valeria; Fabian, Mahrt; Brühwiler, Dominik; Lohmann, Ulrike; Kanji, Zamin
Publication date 05.04.2019
Persistent Identifier (PID) https://doi.org/10.3929/ethz-b-000333046
Repository ETH Research Collection
Abstract
Data set produced over the course of the project

A laboratory investigation of the ice nucleation efficiency of three types of mineral and soil dust

Author Paramonov, Mikhail; David, Robert O.; Kretzschmar, Ruben; Kanji, Zamin A
Publication date 25.04.2019
Persistent Identifier (PID) https://doi.org/10.3929/ethz-b-000303568
Repository ETH Research Collection


Ice nucleation abilities of soot particles determined with the Horizontal Ice Nucleation Chamber

Author Mahrt, Fabian; Marcolli, Claudia; David, Robert O.; Grönquist, Philippe; Barthazy Meier, Eszter J.; Lohmann, Ulrike; Kanji, Zamin A
Publication date 14.06.2018
Persistent Identifier (PID) https://doi.org/10.3929/ethz-b-000286409
Repository ETH Research Collection


Collaboration

Group / person Country
Types of collaboration
Claudia Marcolli Switzerland (Europe)
- in-depth/constructive exchanges on approaches, methods or results
- Publication

Scientific events

Active participation

Title Type of contribution Title of article or contribution Date Place Persons involved
European Geophysical Union Poster Does Ice Formation Terminology need to be revised? 07.04.2019 Vienna, Austria David Robert. O.; Kanji Zaminhussein; Rösch Carolin;
Colloquium, Institiute of Atmospheric an Environmental Sciences, Goethe University Individual talk Aerosol Particles as Ice Crystal Seeds in the Troposphere: From nano-pores to ice clouds 24.01.2019 Frankfurt, Germany Kanji Zaminhussein;
Colloquium, Institute for Meteorology and Climate Research (Invited Talk), Karlsruhe Institute of Technology Individual talk Aerosol Particles as Ice Crystal Seeds in the Troposphere: From nano-pores to ice clouds 18.12.2018 Karlsruhe, Karlsruhe Institute of Technology , Germany Kanji Zaminhussein;
16th Swiss Geosciences Meeting Talk given at a conference The Role of Pores on Ice Nucleation 30.11.2018 Bern, Switzerland David Robert. O.; Fahrni Jonas; Brühwiler Dominik; Kanji Zaminhussein;
Geological Sciences Colloquium (Invited Talk), University of Basel Individual talk Aerosol Particles as Ice Crystal Seeds in the Troposphere: From nano-pores to clouds 10.10.2018 Basel , Switzerland Kanji Zaminhussein;
Tellured Aerosol-Cloud-Interaction Meeting, Invited Contributions only Talk given at a conference Aerosol particles as ice crystal seeds in the troposphere: From nano-pores to ice clouds. Aerosols and Cloud 29.07.2018 Telluride, CO, United States of America David Robert. O.; Kanji Zaminhussein;
Conference on Cloud Physics and Atmospheric Radiation, American Meteorological Society Talk given at a conference Redefining deposition nucleation as pore condensation and freezing 09.07.2018 Vancouver, Canada David Robert. O.; Fahrni Jonas; Kanji Zaminhussein; Brühwiler Dominik;
Seminar Invited Talk Individual talk Deposition Nucleation or Pore Condensartion and Freezing? Understanding Ice Nucleation below Water Saturation 07.05.2018 Oberpfaffenhofen, Germany David Robert. O.;
2nd Atmospheric Ice Nucleation Conference Talk given at a conference Using functionalized mesoporous silica to investigate pore condensation and freezing 26.02.2018 Grasellenbach, Germany Fahrni Jonas; Kanji Zaminhussein; David Robert. O.; Brühwiler Dominik;
14th International Conference on the Physics and Chemistry of Ice Talk given at a conference Deposition nucleation or pore condensation freezing? The role of pores on ice nucleation 07.01.2018 Zurich , Switzerland Kanji Zaminhussein; Brühwiler Dominik; David Robert. O.; Fahrni Jonas;
American Geophyiscal Union, Invited Talk Talk given at a conference Ice Nucleation of Soot Particles in the Cirrus Regime: Is Pore Condensation and Freezing Relevant for Soot? 11.12.2017 New Orleans, United States of America Fahrni Jonas; Brühwiler Dominik; Kanji Zaminhussein; David Robert. O.;
Current Overview of Atmospheric Sciences Meeting, Invited Talk Talk given at a conference Aerosol particles as ice crystal seeds in the troposphere: From nano-pores to clouds 21.08.2017 Mexico City, Centre for Atmospheric Sciences, UNAM, Mexico Kanji Zaminhussein;
European Geophysical Union Poster Deposition Nucleation or Pore Condensation and Freezing? 09.04.2017 Vienna, Austria David Robert. O.; Brühwiler Dominik; Fahrni Jonas; Kanji Zaminhussein;
Fifth workshop- Microphysics of ice clouds Talk given at a conference Invesrigating pore condensation and freezing: the dependence on contact angle 08.04.2017 Vienna, Austria Kanji Zaminhussein; Fahrni Jonas; Brühwiler Dominik; David Robert. O.;
Aerosol Society focus meeting on Atmospheric ice nucleation Talk given at a conference . Pore dependent freezing: Is Deposition Nucleation real? 16.01.2017 Leeds, Great Britain and Northern Ireland Fahrni Jonas; Brühwiler Dominik; Kanji Zaminhussein; David Robert. O.;


Communication with the public

Communication Title Media Place Year
Media relations: print media, online media New understanding of how ice forms in cirrus clouds Department of Environmental System Science Websute International German-speaking Switzerland 2019
Media relations: print media, online media We've been thinking of how ice forms in cirrus clouds all wrong EurekAlert and AAAS International 2019

Awards

Title Year
Best Oral Presentation, Aerosol Society 2017

Associated projects

Number Title Start Funding scheme
150169 Laboratory studies on the ice nucleation properties of fresh and aged mineral dust aerosols 01.11.2013 Project funding (Div. I-III)
175824 Exploiting orographic clouds for constraining the sources of ice crystals 01.10.2017 Project funding (Div. I-III)

Abstract

Ice formation in the atmosphere is an important process that is relatively poorly understood given how important it is for accurately estimating climate parameters and atmospheric composition. Quantifying the atmosphere’s water vapour, trace gas and radiation budget all require accurate prediction of the ice phase and thus atmospheric ice formation. Ice particles can form via homogeneous and heterogeneous ice nucleation. For the latter, insoluble particles called ice nuclei aid the ice nucleation process by providing a surface for ice germ formation. Despite the past three decades representing major advances in developing parameterizations for atmospheric ice formation based on laboratory and field studies, the molecular level understanding of how the surface of an atmospheric particle influences ice formation in the atmosphere is still poorly understood. As such, parameterizations developed based on empirical evidence do not provide a physical basis to determine the particle properties that promote ice nucleation. It is unclear if bulk thermodynamic conditions that we measure and control accurately are sufficient to predict the ice nucleation mechanism occurring under the prescribed conditions at the molecular level on the particle surface. From the four heterogeneous ice nucleation mechanisms, deposition nucleation is the only one that should not involve a liquid phase but occur by direct vapour deposition. Recently, this view has been challenged by the hypothesis, that ice nucleation below water saturation occurs by pore condensation and freezing. Motivated by this we hypothesize that deposition nucleation and condensation freezing are just special cases of immersion freezing. Here in, we propose to synthesise mesoporous silica particles with defined pore sizes and surface or pore chemical functional (alkyl or hydroxyl) groups to test the hypothesis with ice nucleation experiments. The specific research questions to be addressed in this proposal are: 1)What pore size is required to crystallise water at relative humidity below water saturation? (task 1)2)Does the surface or the pores of the particle influence ice nucleation? (task 2)3)Do small pores trap condensed water and freeze at conditions relevant for deposition mode ice formation (task 3)? 4)Does the magnitude of immersion and condensation freezing on a particle differ from each other given that ice forms from the liquid phase for both mechanisms? (task 4) The research results generated from this work will have a large impact on our understanding of the types and number of ice nucleation mechanisms that are relevant for atmospheric ice cloud formation.
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