GSWM Sample Output: April Temperature Semidiurnal Tide

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Apr Temp Semi: Alt v. Lat
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Contour plot of the temperature perturbation field of the semidiurnal tide in April as a function of altitude, latitude, and local time. Dashed lines and blue colors indicate perturbations in degrees K (C) below the background temperature field. This cross section is independent of longitude.

The phase velocity is downward, though the tide propagates upward with a wavelength of about 30-35km.

Note the roughly symmetric peaks about the equator at +/- 40 degrees latitude, above 100km. The phase of the tide is the same across the equator, with a peak of opposite phase and roughly equal magnitude right over the equator.

Compare with the slightly lower magnitude diurnal temperature field which begins propagating at a lower altitude over the equator.