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Biological ice nucleators at tropospheric cloud height

English title Biological ice nucleators at tropospheric cloud height
Applicant Conen Franz
Number 140228
Funding scheme Project funding (Div. I-III)
Research institution Institut für Umweltgeowissenschaften Universität Basel
Institution of higher education University of Basel - BS
Main discipline Climatology. Atmospherical Chemistry, Aeronomy
Start/End 01.09.2012 - 31.08.2015
Approved amount 183'489.00
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All Disciplines (2)

Discipline
Climatology. Atmospherical Chemistry, Aeronomy
Environmental Research

Keywords (5)

biological; Pseudomonas syringae; aerosol; ice nucleation; atmosphere

Lay Summary (English)

Lead
Lay summary

In this project we will characterize biological ice nucleators from the atmosphere for the long term objective of determining whether, when and how these biological particles cause clouds to precipitate. The 3-year project will involve field work to collect samples at the High Altitude Research Station Jungfraujoch, laboratory work in microbiology and chemistry at the University of Basel and at INRA in Avignon, and collaboration with atmospheric physicists at Empa and at PSI making for a truely interdisciplinary research project.

Biological ice nucleators (IN) are the most abundant agents to catalyze ice formation at warm temperatures (> -10 oC). Yet, the relevance of biological ice nucleation for cloud processes, such as initiating precipitation, remains ambiguous. Very little is known about abundance and nucleation spectra of biological IN at tropospheric cloud altitudes. Equally unknown is the relative importance of different kinds of biological IN in this part of the atmosphere, its likely change with seasons, with weather and air mass origin. In this project four major questions will be addressed to shed more light on these issues:

1.         What are the abundance and nucleation spectra of warm-temperature ice nuclei (active between -3 and -13 oC) at tropospheric cloud altitude? 

2.         Do abundance and nucleation spectra correlate with (a) season / weather, (b) source region and/or (c) aerosol number-size distribution of air masses?

3.         What are the relative contributions to the total number of IN by intact micro-organisms and by biological residues on soil dust?

4.         Do we find Pseudomonas syringae, currently considered the most ubiquitous and most efficient warm-temperature ice nucleus, in air masses with high numbers of IN active at warm temperatures?

Direct link to Lay Summary Last update: 21.02.2013

Responsible applicant and co-applicants

Employees

Publications

Publication
Ice nucleators, bacterial cells and Pseudomonas syringae in precipitation at Jungfraujoch
Stopelli Emiliano, Conen Franz, Guilbaud Caroline, Zopfi Jakob, Alewell Christine, Morris Cindy E. (2017), Ice nucleators, bacterial cells and Pseudomonas syringae in precipitation at Jungfraujoch, in Biogeosciences, 14(5), 1189-1196.
Predicting abundance and variability of ice nucleating particles in precipitation at the high-altitude observatory Jungfraujoch
Stopelli Emiliano, Conen Franz, Morris Cindy E., Herrmann Erik, Henne Stephan, Steinbacher Martin, Alewell Christine (2016), Predicting abundance and variability of ice nucleating particles in precipitation at the high-altitude observatory Jungfraujoch, in Atmospheric Chemistry and Physics, 16(13), 8341-8351.
Ice nucleation active particles are efficiently removed by precipitating clouds
Stopelli Emiliano, Conen Franz, Morris Cindy E., Herrmann Erik, Bukowiecki Nicolas, Alewell Christine (2015), Ice nucleation active particles are efficiently removed by precipitating clouds, in Scientific Reports, 5(1), 16433-16433.
Atmospheric ice nuclei at the high-altitude observatory Jungfraujoch, Switzerland
Conen Franz, Rodriguez Sergio, Hüglin Christoph, Henne Stephan, Herrmann Erik, Bukowiecki Nicolas, Alewell Christine (2015), Atmospheric ice nuclei at the high-altitude observatory Jungfraujoch, Switzerland, in Tellus B, 67, 25014.
Freezing nucleation apparatus puts new slant on study of biological ice nucleators in precipitation
Stopelli E., Conen F., Zimmermann L., Alewell C., Morris C. E. (2014), Freezing nucleation apparatus puts new slant on study of biological ice nucleators in precipitation, in ATMOSPHERIC MEASUREMENT TECHNIQUES, 7(1), 129-134.

Collaboration

Group / person Country
Types of collaboration
Air Pollution / Environmental Technology, Empa Switzerland (Europe)
- in-depth/constructive exchanges on approaches, methods or results
Plant Pathology Research, Institut national de la recherche agronomique (INRA) France (Europe)
- in-depth/constructive exchanges on approaches, methods or results
- Publication
Aerosol Physics Group, Laboratory of Atmospheric Chemistry, Paul Scherrer Institute (PSI) 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
EGU 2015 session AS 1.9 on Mixed-Phase clouds Talk given at a conference Biological ice nuclei are rapidly lost from precipitating clouds 13.04.2015 Vienna, Austria Stopelli Emiliano; Conen Franz;
EGU 2015 session AS 1.9 on Mixed-Phase clouds Poster Microzoo: assessing the diversity of biological ice nuclei in rain and snow 13.04.2015 Vienna, Austria Stopelli Emiliano; Conen Franz;
3rd ESF workshop on Atmospheric Ice Nucleation Talk given at a conference Dynamics of biological ice nuclei in precipitation 11.04.2015 Veinna, Austria Stopelli Emiliano;
MILAF Workshop (Microorganisms at the Interface Land-Atmosphere Feedbacks) Talk given at a conference talk on my research and active participation to workshop activities and working groups 13.10.2014 St Maxime, France Conen Franz; Stopelli Emiliano;
EGU 2014 session AS 3.6 on Atmospheric Ice Nuclei Talk given at a conference Biological ice nucleation at tropospheric cloud heights: potential conditioning of precipitation 28.04.2014 Vienna, Austria Stopelli Emiliano;
2nd ESF workshop on Atmospheric ice nucleation Talk given at a conference A new immersion freezing apparatus for biological ice nucleation 26.04.2014 Vienna, Austria Stopelli Emiliano;
seminar at INRA, Avignon Individual talk Abundance of biological ice nucleators in precipitations. Results and perspectives after one year of observations 07.02.2014 Avignon, France Stopelli Emiliano;
MICROBAERO 2013 Talk given at a conference Abondance des noyaux biologiques de glace dans les précipitations. Résultats et perspectives après une année d'observations 07.10.2013 La Bourbule, Clermont Ferrand, France Conen Franz; Stopelli Emiliano;
14th Swiss Global Change Day Poster biological ice nucleation at tropospheric cloud heights 16.04.2013 Bern, Switzerland Conen Franz; Stopelli Emiliano;
ESF workshop on Atmospheric ice nucleation Talk given at a conference biological ice nucleation at tropospheric cloud heights 06.04.2013 Vienna, Austria Stopelli Emiliano;
5th Swiss microbiological meeting Poster biological ice nucleation at tropospheric cloud heights 04.02.2013 Löwenberg, Switzerland Stopelli Emiliano;


Communication with the public

Communication Title Media Place Year
Talks/events/exhibitions Basel UniRat Besuch-Naturwissenschaften Fakultät Western Switzerland 2014
New media (web, blogs, podcasts, news feeds etc.) project website International 2014

Awards

Title Year
Prix de Quervain 2017

Associated projects

Number Title Start Funding scheme
169620 Relevance of biological particles in atmospheric ice formation at moderate supercooling 01.04.2017 Project funding (Div. I-III)
117622 Improving the verification of non-CO2 greenhouse gas emissions in Europe by the Rn-222 tracer method 01.02.2008 Project funding (Div. I-III)
159194 Biological ice nucleators at tropospheric cloud height (4th year) 01.09.2015 Project funding (Div. I-III)

Abstract

Biological ice nucleators (IN) are the most abundant agents to catalyze ice formation at warm temperatures (> -10 oC). Yet, the relevance of biological ice nucleation for cloud processes, such as initiating precipitation, remains ambiguous. Very little is known about abundance and nucleation spectra of biological IN at tropospheric cloud altitudes. Equally unknown is the relative importance of different kinds of biological IN in this part of the atmosphere, its likely change with seasons, with weather and air mass origin. In this project we address four major questions to shed more light on these issues: 1.What are the abundance and nucleation spectra of warm-temperature ice nuclei (active between -3 and -13 oC) at tropospheric cloud altitude? 2.Do abundance and nucleation spectra correlate with (a) season / weather, (b) source region and/or (c) aerosol number-size distribution of air masses?3.What are the relative contributions to the total number of IN by intact micro-organisms and by biological residues on soil dust? 4.Do we find Pseudomonas syringae, currently considered the most ubiquitous and most efficient warm-temperature ice nucleus, in air masses with high numbers of IN active at warm temperatures? Field work will take place at the High Alpine Research Station Jungfraujoch located in the Swiss Alps at 3580 m above sea level. Air masses surrounding the station are presumed to be representative for the lower troposphere above the continent (more precise characterisation will be done with our two atmospheric 222Rn monitors at Bern and on Jungfraujoch (http://radon.unibas.ch/) as part of ongoing work at the institute, but outside the scope of this proposal). The station is frequently within clouds. To address our questions, air will be sampled over two years during a total of 18 weeks with liquid impingers and analysed at the station in drop freeze tests for abundance and nucleus spectra (Question 1). High-resolution transport simulations (FLEXPART) by our collaborator Dr. Stefan Henne (Air Pollution / Environmental Technology, Empa, Switzerland) will enable us to identify the main source regions (Question 2b). Data on number-size distributions of total aerosol during our sampling campaigns (Question 2c) becomes available through the collaboration with Dr. Ernest Weingartner (Head, Aerosol Physics Group, Laboratory of Atmospheric Chemistry, PSI, Switzerland). Differentiation between bacteria, spores, and biological residues associated with soil dust (Question 3), and isolation of Pseudomonas syringae, (Question 4) is done in close collaboration with the group of Dr. Cindy Morris (Director, Plant Pathology Research, INRA, Avignon, France).
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