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<article language="en">
	<journal>
		<journal_title>Biogeosciences</journal_title>
		<journal_url>www.biogeosciences.net</journal_url>
		<issn>1726-4170</issn>
		<eissn>1726-4189</eissn>
		<volume_number>4</volume_number>
		<issue_number>6</issue_number>
		<publication_year>2007</publication_year>
	</journal>
	<doi>10.5194/bg-4-1059-2007</doi>
	<article_url>http://www.biogeosciences.net/4/1059/2007/</article_url>
	<abstract_html>http://www.biogeosciences.net/4/1059/2007/bg-4-1059-2007.html</abstract_html>
	<fulltext_pdf>http://www.biogeosciences.net/4/1059/2007/bg-4-1059-2007.pdf</fulltext_pdf>
	<start_page>1059</start_page>
	<end_page>1071</end_page>
	<publication_date>2007-12-03</publication_date>
	<article_title content_type="html">Microbiology and atmospheric processes: the role of biological particles in cloud physics</article_title>
	<authors>
		<author numeration="1" affiliations="1">
			<name>O. MÃ¶hler</name>
			<email>ottmar.moehler@imk.fzk.de</email>
		</author>
		<author numeration="2" affiliations="2">
			<name>P. J. DeMott</name>
		</author>
		<author numeration="3" affiliations="3">
			<name>G. Vali</name>
		</author>
		<author numeration="4" affiliations="4">
			<name>Z. Levin</name>
		</author>
	</authors>
	<affiliations>
		<affiliation numeration="1" content_type="html">Institute for Meteorology and Climate Research (IMK-AAF), Forschungszentrum Karlsruhe, Germany</affiliation>
		<affiliation numeration="2" content_type="html">Department of Atmospheric Science, Colorado State University, Fort Collins, CO, USA</affiliation>
		<affiliation numeration="3" content_type="html">Department of Atmospheric Science, University of Wyoming, Laramie, WY, USA</affiliation>
		<affiliation numeration="4" content_type="html">Department of Geophysics and Planetary Science, The Raymond and Beverly Sackler Faculty of Exact Sciences, Tel Aviv University, Israel</affiliation>
	</affiliations>
	<abstract content_type="html">As part of a series of papers on the sources, distribution and potential
impact of biological particles in the atmosphere, this paper introduces and
summarizes the potential role of biological particles in atmospheric clouds.
Biological particles like bacteria or pollen may be active as both cloud
condensation nuclei (CCN) and heterogeneous ice nuclei (IN) and thereby can
contribute to the initial cloud formation stages and the development of
precipitation through giant CCN and IN processes. The paper gives an
introduction to aerosol-cloud processes involving CCN and IN in general and
provides a short summary of previous laboratory, field and modelling work
which investigated the CCN and IN activity of bacterial cells and pollen.
Recent measurements of atmospheric ice nuclei with a continuous flow
diffusion chamber (CFDC) and of the heterogeneous ice nucleation efficiency
of bacterial cells are also briefly discussed. As a main result of this
overview paper we conclude that a proper assessment of the impact of
biological particles on tropospheric clouds needs new laboratory, field and
modelling work on the abundance of biological particles in the atmosphere and
their CCN and heterogeneous IN properties.</abstract>
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</article>

