Increased ionization supports growth of aerosols into cloud condensation nuclei

by H. Svensmark et al., December 19, 2017 in NatureCommunications

 (…)In conclusion, a mechanism by which ions condense their mass onto small aerosols and thereby increase the growth rate of the aerosols, has been formulated theoretically and shown to be in good agreement with extensive experiments. The mechanism of ion-induced condensation may be relevant in the Earth’s atmosphere under pristine conditions, and able to influence the formation of CCN. It is conjectured that this mechanism could be the explanation for the observed correlations between past climate variations and cosmic rays, modulated by either solar activity or supernova activity in the solar neighborhood on very long time scales. The theory of ion-induced condensation should be incorporated into global aerosol models, to fully test the atmospheric implications.

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