title: The relevance of nanoscale biological fragments for ice nucleation in clouds.
abstract: Most studies of the role of biological entities as atmospheric ice-nucleating particles have focused on relatively rare supermicron particles such as bacterial cells, fungal spores and pollen grains. However, it is not clear that there are sufficient numbers of these particles in the atmosphere to strongly influence clouds. Here we show that the ice-nucleating activity of a fungus from the ubiquitous genus Fusarium is related to the presence of nanometre-scale particles which are far more numerous, and therefore potentially far more important for cloud glaciation than whole intact spores or hyphae. In addition, we quantify the ice-nucleating activity of nano-ice nucleating particles (nano-INPs) washed off pollen and also show that nano-INPs are present in a soil sample. Based on these results, we suggest that there is a reservoir of biological nano-INPs present in the environment which may, for example, become aerosolised in association with fertile soil dust particles.
authors.affiliation: Institute for Climate and Atmospheric Science, School of Earth &Environment, University of Leeds, UK.
authors.forename: D
authors.initials: D
authors.lastname: O'Sullivan
authors.affiliation: Institute for Climate and Atmospheric Science, School of Earth &Environment, University of Leeds, UK.
authors.forename: B J
authors.initials: BJ
authors.lastname: Murray
authors.affiliation: School of Chemistry and Astbury Centre for Structural Molecular Biology, University of Leeds, UK.
authors.forename: J F
authors.initials: JF
authors.lastname: Ross
authors.affiliation: Institute for Climate and Atmospheric Science, School of Earth &Environment, University of Leeds, UK.
authors.forename: T F
authors.initials: TF
authors.lastname: Whale
authors.affiliation: Institute for Climate and Atmospheric Science, School of Earth &Environment, University of Leeds, UK.
authors.forename: H C
authors.initials: HC
authors.lastname: Price
authors.affiliation: 1] Institute for Climate and Atmospheric Science, School of Earth &Environment, University of Leeds, UK [2] Now at Institute for Atmospheric and Climate Science, Universitaetstr. 16, ETH Zurich, Switzerland.
authors.forename: J D
authors.initials: JD
authors.lastname: Atkinson
authors.affiliation: Institute for Climate and Atmospheric Science, School of Earth &Environment, University of Leeds, UK.
authors.forename: N S
authors.initials: NS
authors.lastname: Umo
authors.affiliation: School of Chemistry and Astbury Centre for Structural Molecular Biology, University of Leeds, UK.
authors.forename: M E
authors.initials: ME
authors.lastname: Webb
mesh_terms: D001272:Atmosphere; D029662:Betula / Q000737:chemistry; D002850:Chromatography, Gel; D005670:Fusarium / Q000737:chemistry*; D007053:Ice; D008962:Models, Theoretical; D008970:Molecular Weight; D025282:Mycelium / Q000737:chemistry; D053758:Nanoparticles / Q000737:chemistry*; D010316:Particle Size; D011058:Pollen / Q000737:chemistry*; D012987:Soil / Q000737:chemistry; D014867:Water / Q000737:chemistry
chemical_list: D007053:Ice; D012987:Soil; D014867:Water