Comparison of Turbulence Over Japan and New Mexico from MST Radar Observations
Abstract
Observations from Mesosphere-Stratosphere-Troposphere (MST) radars at White Sands, New Mexico, Vandenburg, California, and Shigaraki, Japan, are used to study the relationships between the intensity of refractivity turbulence and large-scale weather conditions. (a) The gravity wave intensity seen by satellites (GPS/MET) agrees with that seen by the radar at White Sands. (b) The gravity wave source mechanisms are different at White Sands and Japan, although the wave energies are about the same magnitude. (c) The intensity of refractivity turbulence in the stratosphere, above 18 km, is not changed by the presence of thunderstorms in the troposphere. (d) The diurnal changes in the intensity of refractivity turbulence and in the spectral width are very small during all seasons at both White Sands and Japan. (e) The intensity of refractivity turbulence in the stratosphere is highly correlated with relative vorticity. Since the correlation is improved when distance from the tropopause is used as the vertical coordinate and when the data are normalized by local atmospheric density, the model developed is thus a combined conceptual/physical/statistical model. (f) A case study at Vandenburg shows that turbulence and wave intensities increase during the passage of a cyclone in the presence of a strong surface inversion. (g) Case studies in Japan show that turbulence intensities in the lower stratosphere are often more closely related to the intensity of gravity waves than to in situ wind speed and large-scale wind vertical shear.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 08, 2002
- Accession Number
- ADA398873
Entities
People
- Gregory D. Nastrom