TY - JOUR
T1 - The ION-CAGE Code
T2 - A Numerical Model for the Growth of Charged and Neutral Aerosols
AU - Svensmark, J.
AU - Shaviv, N. J.
AU - Enghoff, M. B.
AU - Svensmark, H.
N1 - Funding Information: J. S. is funded by the Danish council for independent research under the project “Fundamentals of Dark Matter Structures”, DFF‐6108‐00470. N. J. S. wishes to thank the generous support of the Israeli Ministry of Energy, Grant 218‐11‐036. J. S. thanks Caroline Richardt Beck for illustration design assistance and Asbjørn Jacobsen for identifying typos in two equations. Publisher Copyright: ©2020. The Authors.
PY - 2020/9/1
Y1 - 2020/9/1
N2 - The presence of small ions influences the growth dynamics of a size distribution of aerosols. Specifically, the often neglected mass of small ions influences the aerosol growth rate, which may be important for terrestrial cloud formation. To this end, we develop the Ion and Charged Aerosol Growth Enhancement (ION-CAGE) code, a numerical model to calculate the growth of a species of aerosols in the presence of charge, which explicitly includes terms for ion condensation. It is shown that a positive contribution to aerosol growth rate is obtained by increasing the ion-pair concentration through this ion condensation effect, consistent with recent experimental findings. The ion condensation effect is then compared to aerosol growth from charged aerosol coagulation, which is seen to be independent of ion-pair concentration. Growth rate enhancements by ion condensation are largest for aerosol sizes less than ∼25 nm and increases proportional to the ion concentration. The effect of ion condensation is expected to be most important over pristine marine areas. The model source code is made available through a public repository.
AB - The presence of small ions influences the growth dynamics of a size distribution of aerosols. Specifically, the often neglected mass of small ions influences the aerosol growth rate, which may be important for terrestrial cloud formation. To this end, we develop the Ion and Charged Aerosol Growth Enhancement (ION-CAGE) code, a numerical model to calculate the growth of a species of aerosols in the presence of charge, which explicitly includes terms for ion condensation. It is shown that a positive contribution to aerosol growth rate is obtained by increasing the ion-pair concentration through this ion condensation effect, consistent with recent experimental findings. The ion condensation effect is then compared to aerosol growth from charged aerosol coagulation, which is seen to be independent of ion-pair concentration. Growth rate enhancements by ion condensation are largest for aerosol sizes less than ∼25 nm and increases proportional to the ion concentration. The effect of ion condensation is expected to be most important over pristine marine areas. The model source code is made available through a public repository.
UR - http://www.scopus.com/inward/record.url?scp=85091428228&partnerID=8YFLogxK
U2 - https://doi.org/10.1029/2020EA001142
DO - https://doi.org/10.1029/2020EA001142
M3 - Article
SN - 2333-5084
VL - 7
JO - Earth and Space Science
JF - Earth and Space Science
IS - 9
M1 - e2020EA001142
ER -