Es structure using an HF radar
Article first published online: 7 DEC 2012
Copyright 1986 by the American Geophysical Union.
Volume 21, Issue 3, pages 309–312, May-June 1986
How to Cite
1986), Es structure using an HF radar, Radio Sci., 21(3), 309–312, doi:10.1029/RS021i003p00309., and (
- Issue published online: 7 DEC 2012
- Article first published online: 7 DEC 2012
- Manuscript Accepted: 16 OCT 1985
- Manuscript Received: 25 JUN 1985
By using an HF radar which produces a steerable beam about 4° wide and measures angle of arrival and Doppler shift of radio echoes, the structure of various types of mid-latitude sporadic E (Es) has been determined. Totally reflecting Es is a very smooth layer, tilted less than 1° from the horizontal. Partially reflecting Es consists of clouds of ionization. These clouds vary in size from a few kilometers to 25 km in the direction of movement and larger in the transverse direction. Echoes often disappear rapidly: the clouds either disappear quickly or have sharp edges. Spread Es has a curious structure of small clouds, each of which reflects only for a few seconds, but each cloud moves with the same velocity, typically 100 m/s, even though the heights of the clouds vary up to 10 km. It is difficult to reconcile this finding with the presence of wind shears.