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pure and applied geophysics

, Volume 112, Issue 2, pp 301–319 | Cite as

Theoretical analysis of lee waves over the Andes as seen by satellite pictures

  • R. P. Sarker
  • R. V. Calheiros
Article

Summary

Satellite pictures have been utilised to detect mountain waves on the lee of the Andes range. The wavelengths as observed in the pictures from the distribution of clouds in parallel bands lie between 20 and 30 km for the five cases examined. The wavelengths have also been computed theoretically for these cases by an analytical method and a quasi-numerical method, using linearised perturbation equations. Wavelengths so computed are in fairly good agreement with the observed wavelengths, Vertical velocities associated with the waves along the different sectors of the Andes have also been computed. Their maximum values are of the order of 1–5 m sec−1. Also, the quasi-stationary character of the waves, as noticed in some of the pictures, is discussed.

Keywords

Theoretical Analysis Vertical Velocity Linearise Perturbation Perturbation Equation Parallel Band 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Birkhäuser-Verlag 1974

Authors and Affiliations

  • R. P. Sarker
    • 1
  • R. V. Calheiros
    • 2
  1. 1.Instituto de Pesquisas Espaciais (INPE)São José dos CamposBrasil
  2. 2.India Meteorological DepartmentIndia

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