Use of Scattering Techniques in Cloud Microphysics Research 1. The Aureole Method
Abstract
A simple, physically clear method is discussed for assessing the amount of atmospheric turbidity on a cloudless day by observing the circumsolar aureole--the ring of brightness around the sun--and comparing its brightness with that of the equivalent Rayleigh scattering (particle-free) atmosphere. The aureole is known to be caused by aerosols. This report applies exact Mie theory phase functions for idealized polydispersions of spherical particles to account for the aureole. It shows that the brightness gradient within a disc of 10-deg radius around the sun indicates the size distribution of the aerosol particles, and the overall extent of the aureole within 40 deg around the sun indicates the degree of turbidity.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 01, 1970
- Accession Number
- AD0714582
Entities
People
- D. Deirmendjian
Organizations
- RAND Corporation