The Interaction and Variation of Waves and Turbulence from MST Radar Data
Abstract
This report summarizes research results on the interactions of gravity waves, small-scale turbulence, and the background weather conditions obtained using data from clear-air Doppler profilers (also called MST radars), and from aircraft and balloons. The major results from these studies are as follows: (1) It was found from analysis of a set of aircraft data taken near the tropopause and from MST radar taken in Alaska and Colorado that there is enhanced mesoscale variability over mountains compared to over plains or oceans. These observational results were compared with predictions from the theory of stratified turbulence and theory of Doppler-shifted gravity waves, and it was found that neither theory predicts all of the observed features. (2) Modeling of the refractivity turbulence structure constant (cn2) showed that small-scale shears of the horizontal wind are about twice as large over the mountainous regions of Colorado compared to over the plains of Illinois, presumably due to terrain differences. (3) It was found that gravity wave activity is enhanced near fronts, jet streams, and convective elements. (4) The flatland MST radar was used to monitor tropopause folding events under a variety of background conditions and a preliminary climatology of the occurrence of folds was developed. (5) The spectrum of vertical motions at Flatland was analyzed and was found to closely match predictions for a spectrum of Doppler-shifted gravity waves. (6) Temporal mean vertical velocities measured by the radar reflect the large-scale flow when weather systems are changing slowly enough that the radar sample is representative of a large area.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 31, 1989
- Accession Number
- ADA212849
Entities
People
- Gregory D. Nastrom
- J. L. Green
- J. M. Warnock
- Kenneth S. Gage
- Miriam R. Peterson
- R. R. Beland
- T. E. Van Zandt
- W. L. Ecklund
Organizations
- Control Data Corporation