TY  - JOUR
A1  - Ignatius, Karoliina
A1  - Kristensen, Thomas Bjerring
A1  - Järvinen, Emma
A1  - Nichman, Leonid
A1  - Fuchs, Claudia
A1  - Gordon, Hamish
A1  - Herenz, Paul
A1  - Hoyle, Christopher Robert
A1  - Duplissy, Jonathan
A1  - Garimella, Sarvesh
A1  - Dias, Antonio
A1  - Frege, Carla
A1  - Höppel, Florian Niko
A1  - Tröstl, Jasmin
A1  - Wagner, Robert
A1  - Yan, Chao
A1  - Amorim, Antonio
A1  - Baltensperger, Urs
A1  - Curtius, Joachim
A1  - Donahue, Neil McPherson
A1  - Gallagher, Martin William
A1  - Kirkby, Jasper
A1  - Kulmala, Markku
A1  - Möhler, Ottmar
A1  - Saathoff, Harald
A1  - Schnaiter, Martin
A1  - Tomé, Antonio
A1  - Virtanen, Annele
A1  - Worsnop, Douglas R.
A1  - Stratmann, Frank
T1  - Heterogeneous ice nucleation of viscous secondary organic aerosol produced from ozonolysis of α-pinene
T2  - Atmospheric chemistry and physics. Discussions
N2  - There are strong indications that particles containing secondary organic aerosol (SOA) exhibit amorphous solid or semi-solid phase states in the atmosphere. This may facilitate deposition ice nucleation and thus influence cirrus cloud properties. However, experimental ice nucleation studies of biogenic SOA are scarce. Here, we investigated the ice nucleation ability of viscous SOA particles. 
The SOA particles were produced from the ozone initiated oxidation of α-pinene in an aerosol chamber at temperatures in the range from −38 to −10 ◦C at 5–15 % relative humidity with respect to water to ensure their formation in a highly viscous phase state, i.e. semi-solid or glassy. The ice nucleation ability of SOA particles with different sizes was investigated with a new continuous flow diffusion chamber. For the first time, we observed heterogeneous ice nucleation of viscous α-pinene SOA in the deposition mode for ice saturation ratios between 1.3 and 1.4 significantly below the homogeneous freezing limit. The maximum frozen fractions found at temperatures between −36.5 and −38.3 °C ranged from 6 to 20 % and did not depend on the particle surface area. Global modelling of monoterpene SOA particles suggests that viscous biogenic SOA particles are indeed present in regions where cirrus cloud formation takes place. Hence, they could make up an important contribution to the global ice nuclei (IN) budget.
Y1  - 2015
UR  - http://publikationen.ub.uni-frankfurt.de/frontdoor/index/index/docId/41892
UR  - https://nbn-resolving.org/urn:nbn:de:hebis:30:3-418922
UR  - http://www.atmos-chem-phys-discuss.net/15/35719/2015/
SN  - 1680-7375
SN  - 1680-7367
N1  - © Author(s) 2015. CC Attribution 3.0 License.
VL  - 15
SP  - 35719
EP  - 35752
PB  - European Geosciences Union
CY  - Katlenburg-Lindau
ER  -