Spectral differences between a gravity shear wave and a continuous superposition of these modes

PULIDO M

ATMOSPHERIC SCIENCE LETTERS

WILEY-V C H VERLAG GMBH

Lugar: Reading UK; Año: 2002 vol. 3 p. 104 - 111

1530-261X

A continuous superposition of gravity waves, propagating upward in a shearing background wind, is analysed. Starting from the gravity wave equations, it is proven, analytically and numerically, that a uniform spectrum has a resultant Doppler-shifted power spectrum with a -3 power law at large vertical wavenumber contrasting with the -1 power law that characterises the power spectrum of the monochromatic wave perturbation profile. The preliminary results presented here show that, assuming conservative propagation (no dissipative processes), the Doppler shifting effect can account for observations.