Atmospheric Aerosol and Cloud Condensation Nuclei Formation: A Possible Influence of Cosmic Rays?
- F. ArnoldAffiliated withAtmospheric Physics Division, Max Planck Institute for Nuclear Physics (MPIK) Email author
Rent the article at a discountRent now
* Final gross prices may vary according to local VAT.Get Access
A physical mechanism which may have a potential to connect climate with cosmic rays (CR) involves aerosol particle formation by CR generated atmospheric ions followed by new particle growth. Only grown particles can scatter sunlight efficiently and can eventually act as cloud condensation nuclei (CCN) and thereby may influence climate. Moreover grown particles live longer as they are less rapidly scavenged by pre-existing larger particles. The present paper discusses aerosol particle formation and growth in the light of new measurements recently made by our MPIK Heidelberg group. Emphasis is placed upon the upper troposphere where very low temperatures tend to facilitate new particle formation by nucleation. The new measurements include: laboratory measurements of cluster ions, aircraft measurements of ambient atmospheric ions, and atmospheric measurements of the powerful nucleating gas H2SO4 and its precursor SO2. The discussion also addresses model simulations of aerosol formation and growth. It is concluded that in the upper troposphere new aerosol formation by CR generated ions is a frequent process with relatively large rates. However new particle formation by homogeneous nucleation (HONU) which is not related to CR also seems to be efficient. The bottleneck in the formation of upper troposphere aerosol particles with sizes sufficiently large to be climate relevant is not nucleation but growth of small particles. Our recent upper troposphere SO2 measurements suggest that particle growth by gaseous sulphuric acid condensation is at least occasionally efficient. If so CR mediated formation of CCN sized particles should at least occasionally be operative in the upper troposphere.
Keywordsaerosols clouds cosmic rays
- Atmospheric Aerosol and Cloud Condensation Nuclei Formation: A Possible Influence of Cosmic Rays?
Space Science Reviews
Volume 125, Issue 1-4 , pp 169-186
- Cover Date
- Print ISSN
- Online ISSN
- Kluwer Academic Publishers
- Additional Links
- cosmic rays
- Industry Sectors
- F. Arnold (1)
- Author Affiliations
- 1. Atmospheric Physics Division, Max Planck Institute for Nuclear Physics (MPIK), P.O. Box 103980, D-69029, Heidelberg, Germany