Analysis of Stress Ionograms.
Abstract
Anomalous radar returns seen on ionograms following ionospheric barium releases are analyzed to determine their origin and their interpretation. Two types of echoes are identified; one type originates from the barium cloud and the other type from layers formed by the descent of barium ions into the E-region. A review is made of sporadic-E literature because some of the explanations of the origin and reflection mechanisms proposed for sporadic-E appear to be applicable to barium echoes. Data from past barium releases were also reviewed to supplement the STRESS data base. The findings indicate that reflection from an overdense layer or target is not the cause of the barium-associated returns. Thus, the maximum frequencies of the returns cannot be interpreted as a maximum plasma frequency. Gradient reflection and scatter from weak or strong irregularities are both plausible mechanisms for both types of echoes. The characteristics of the E-region returns and their likely cause (compression due to wind shear) suggest that these layers are thin with sharp boundaries and a rough underside. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1977
- Accession Number
- ADA056388
Entities
People
- Norman J. F. Chang
Organizations
- SRI International