Abstract
Two methods for detecting turbulence near jet streams are investigated using a VHF radar - the corrected spectral width of the vertical echo and the anisotropy of the signal returned. It is found that turbulent dissipation rates in excess of 0.2 mW kg-1 may be detected using the spectral width, but uncertainties in the derivation of this parameter preclude detection of weak turbulence. Anisotropy of the signal is capable of detecting some turbulence in regions of high static stability, but the method is not quantitative and is best employed to confirm the spectral-width estimates when these are near the detection limit. Independent confirmation that atmospheric conditions were favourable for turbulence was provided by Richardson number profiles derived from the radar and a Raman lidar. Measurements of static stability by the lidar and spectral widths by the radar allow an estimate of the turbulent-dissipation rate. The application of these techniques to two jet stream passages is discussed.
| Original language | English |
|---|---|
| Pages (from-to) | 447-462 |
| Number of pages | 16 |
| Journal | Quarterly Journal of the Royal Meteorological Society |
| Volume | 124 |
| Issue number | 546 |
| DOIs | |
| State | Published - Jan 1998 |
| Externally published | Yes |
Keywords
- Clear-air turbulence
- Radar observations
- Turbulent dissipation