Articles | Volume 17, issue 13
https://doi.org/10.5194/acp-17-8343-2017
https://doi.org/10.5194/acp-17-8343-2017
Research article
 | 
10 Jul 2017
Research article |  | 10 Jul 2017

On the limits of Köhler activation theory: how do collision and coalescence affect the activation of aerosols?

Fabian Hoffmann

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Cited articles

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Short summary
This study analyzes at which aerosol radius the mass growth leading to activation switches from diffusion to collection, marking the limit of traditional Köhler activation theory. It is found that collection becomes increasingly important for aerosols larger than 0.1 µm in dry radius and is responsible for all activations of aerosols larger than 1.0 µm. A novel particle-based cloud modeling approach is applied, in which activation can be represented without parameterizations.
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