A Comparison of Optically Measured and Radar-Derived Horizontal Neutral Winds
Abstract
Nighttime thermospheric winds for Sondrestrom, Greenland from 11 nights between 1983 and 1988, have been compared to learn about the O(+)-O collision cross section and the high-latitude atomic oxygen density. The horizontal winds in the magnetic meridian were derived indirectly from incoherent-scatter radar (ISR) measurements on ion velocities antiparallel to the magnetic field and directly from Fabry-Perot interferometer (FPI) measurements of Doppler shifts of the (6300-A) emission of atomic oxygen. In deriving the radar winds, the O(+)-O collision cross section, was scaled by a factor of f what was varied from 0.5 to 5.1. On the basis of several arguments the altitude of the 6300-A emission was assumed to be 230 km. The best agreement between the ISR and FPI winds was obtained when f was increased substantially, to between 1.7 and 3.4. If the average peak emission altitude were higher, these factors would be larger; if it were lower, they would be somewhat smaller. However, if the average altitude were substantially lower it would have been more difficult to have obtained agreement between the two techniques. (R.H.)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1990
- Accession Number
- ADA227690
Entities
People
- Michael S. Christie
Organizations
- Air Force Institute of Technology