Symposium on
"Biological Ice Nucleators in the Atmosphere - at the Crossroads of Physics and Biology"
Perugia, Italy -- 10 July 2007

A special session with the above title was held as part of the IUGG XXIV General Assembly, as an IAMAS/ICCP symposium. (A grant from the U.S. National Science Foundation funded in part the preparation of this meeting, and assisted with participant travel costs.)

During the one-day meeting, 23 papers were presented, including 4 keynote talks.

The list of presentation is included below, with links to the abstracts, to the full presentations and with links to publications. The order of the papers in the list follows the sequence in which they were included in the program.

               TITLE        AUTHOR(S)
INTRODUCTION    History, accomplishments and major issues to resolve. Gabor Vali full
KEYNOTE PAPER     The discovery of biological ice nuclei: early successes, missteps and some remaining questions.R.C. Schnell absfull
High-resolution ice nucleation spectra of sea-ice bacteria: Implications for cloud formation and life in frozen environments. B. Swanson, K. Jungeabsfull link
Evidence for biological ice nucleating particles in snowfall.B. Christner, C. Morris, R. Cai, M. Skidmore, S. Montross, Ch. Foreman, D. Sandsabslink
The ability of leaf litter debris to initiate ice phase formation in the atmosphere.K. Koehler, S.M. Kreidenweis, P.J. DeMott, A. Guenther, R.Fallabsfull
Isolation of ice-nucleation active microrganisms from cloud water.A-M. Delort, P. Amato, M. Sancelmeabsfull
KEYNOTE PAPER    Is there a role for ice nucleation activity in bacterial dissemination?D. Sands, C.E. Morris, D.G. Georgakopoulosabs full
Biological characterization of atmospheric aerosol particles.J. Nowoisky, V. Despres, J. Cimbal, M. Klose, R. Conrad, M.O. Andreae, U. Poeschlabs
Diversity of bacteria producing pigmented colonies in aerosol, snow and soil samples from remote glacial areas (Antarctica, Alps, Andes).E. Gonzalez-Toril, R.J. Delmas, J.-R. Petit, J. Komarek, R. Amils, J. Elsterabs full
Contribution of fungi to primary biogenic aerosols in the atmosphere: active discharge of spores, carbohydrates, and organic ions by asco- and basidiomycota.W. Elbert, P.E. Taylor, M.O. Andreae, U. Poeschlabsfull
Biogenic ice nuclei studies proposed for the BEACHON project.R. Rasmussen, A. Guentherabs full
KEYNOTE PAPER     Atmospheric ice nuclei concentrations and characteristics: constraining the role of biological ice nuclei.P. DeMott, M. Richardson, D. Cziczo, A. Prenni, S. Kreidenweisabsfull
New cloud chamber studies on the ice nucleation efficiency of airborne bacteria.O. Moehler, D.G. Georgakopoulos, C. Morrisabs full
Laboratory studies of ice nucleating ability of pollen and model simulations of the effects of biological aerosol particles on cloud microphysics.K. Diehl, M. Simmel, S. Wurzler, N. von Blohn, S.K. Mitraabsfull
Modeling study of the role of bacteria on ice nucleation processes.Jiming Sun, P.A. Ariya, H.G. Leighton, M.K. Yuaabs
Cloud modeling with an empirical parameterization of heterogeneous ice nucleation for multiple aerosol species: role of biogenic particles.V. Phillips, C. Andronache, P. DeMott, C.E. Morris, D.C. Sandsabs
Supercooling in over-wintering pine beetle larvae.R. Schnell, R.C. Schnellabs full
KEYNOTE PAPER     Detecting ice nucleating bacteria in environmental samples using PCR of the gene conferring ice nucleating activity.C. Morris, C. Guilbaud, H. Ahern, H. Dominguez, C. Glaux, B. Moffett, T. Hillabs full
Genetic analysis and diversity of primary biogenic aerosol particles.V. Despres, J. Nowoisky, M. Klose, R. Conrad, M.O. Andreae, U. Poeschlabsfull
Characterization of snowborne taxa and bioaerosols in several Arctic and sub-Arctic sites.M. Amyot, P.A. Ariya, G. Kos, R. Mortazaviabs
Snowborne taxa characterization and impact on ice nucleation.R. Mortazavi, M. Amyot, P.A. Ariyaabs
How to enumerate airborne microorganisms?R. Thyrhaug, J. Einen, R-A. Sandaa, M. Heldal, G. Brtabakabsfull
Fluorescent pseudomonads in Scottish cloud and rain water: diversity, ice nucleation activity and biosurfactant production.T. Hill, H. Ahern, K. Walsh, B. Moffettabs full

Some photographs taken during the meeting and afterwards.   

On the index page of pictures, clicking on an image will bring up an enlarged view of that image. Above that image navigation signs appear to move forward or backwards in the collections, or to return to the index page.

A link of probable interest:

"Properties of biological aerosols and their impact on atmospheric processes." Special Issue of Biogeosciences.

The material below was posted in advance of the meeting.


Biogenic ice nuclei are among the most active of the known ice nucleators, yet their contribution to atmospheric processes has not been clarified. Assessments of an atmospheric role are gathering momentum as techniques of detection improve, as understanding of biological sources is growing, and as observations and modelling of clouds identify the role of early ice nucleation in the formation of precipitation and in determining other cloud characteristics. The session will bring together experts from the atmospheric and biological sciences to review knowledge about the nature and distribution of biogenic ice nuclei, to assess evidence for the role of biogenic ice nuclei in the atmosphere, and for discussions of future research directions. The symposium will include invited and contributed papers and posters.

Lead convenor: Gabor Vali, Dept. Atmospheric Science, University of Wyoming, 1000 E. Ivinson Ave, Laramie, WY 82070, USA, tel:+307-766-3225, fax: +307-766-2635;
Convenor: Cindy E. Morris, INRA, Plant Pathology Research Unit, BP 94, 84140 Montfavet, France. tel: +33 432-72-28-86; fax: +33 432-72-28-42;

Because of the interdisciplinary nature of the topic, the lack of dedicated laboratories or institutes addressing the problem, and the dispersion of relevant publications in many different journals, it is difficult for young investigators and students to know about this topic and to consider working on it. Thus, special emphasis is given by the organizers to attracting young scientists and graduate strudents who are either working on a topic covered by the symposium or who intend to extend their interest to this field. To this end, travel support of roughly $500 may be provided for about 15 attendees. Funding for this is available thanks to a special grant from the National Science Foundation.

In the distribution of travel funds preference will be given to (i) young investigators already engaged in the field and who submit an abstract, and those who can, and likely will, extend their activities in an organic way to encompass the topic, and (ii) graduate students, if their supervisor supports the idea of their undertaking a relevant thesis or dissertation project.

Requests for travel support should be addressed to the Lead Convener. Letters of no more than 150 words should be sent by email or postal mail outlining the attendees plans for participation in the symposium, and beyond. Allocation of the funds will be made by a small committee.

Abstract submission deadline set by IUGG is February 28, 2007 for email transmission, and February 10, 2007 for postal mail. The program for this symposium will be finalized by the end of March, so those planning to present a paper or a poster, and those requesting travel support should contact the conveners as early as possible, but no later than March 10, 2007.

Abstract format and other information can be found via this link.. To have full access to the IUGG XXIV web site it is necessary to first set up a login and password.

Information about other ICCP symposia during IUGG 2007 can be found via this link.

        greenball    The 17th International Conference on Nucleation and Atmospheric Aerosols (ICNAA)
        will be held on August 13-17, 2007, in Galway, Ireland. Click here for more information about that conference.

Some background

          This meeting will take up the theme of biogenic ice nucleation that saw very rapid developments from the mid-1970s to the mid-1990s, with a series of six international conferences marking the pace. Research then settled to a less visible stage of steady utilization of the groundwork that has been laid and to a more gradual accumulation of new knowledge. During that same period, the broader fields of atmospheric chemistry, organic aerosols and related subjects developed at remarkable speed.

Here is a photo of the participants of the 1993 conference.

          In March 2006, a workshop was held in Avignon, supported by the European Science Foundation, titled "Microbiological Meteorology: Working at the Intersection of Biology, Physics and Meteorology to Understand and Regulate the Microbial Component of Weather". A summary of this workshop is here. A photo of the participants can be reached via this link; a list of names and contacts is included in the report mentioned above.

More material about the workshop is available via this link.

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