Search Results

You are looking at 1 - 3 of 3 items for :

  • Author or Editor: Arnold Gruber x
  • Journal of the Atmospheric Sciences x
  • User-accessible content x
Clear All Modify Search
Arnold Gruber

Abstract

The wavenumber–frequency spectra of the 200 mb wind field from 28.7°N to 28.7°S were examined for the 128–day period from mid-May to mid-September of 1970 and 1971. Evidence was presented that supported the existence of Rossby and mixed Rossby–gravity waves. Westward–propagating waves, with periods of about 10 days and wavenumber 10, centered at about 24°N were also observed. These waves appear to he associated with the tropical upper troughs.

There were indications of equatorward transfers of energy from the mid-latitudes at periods of 9–10 and about 5 days.

Full access
Arnold Gruber

Abstract

The relationship between streamline pattern and momentum transport has been examined. It is shown, for divergent flow, that it is possible for a streamline pattern with troughs and ridges oriented northeast-southwest to have zonally averaged momentum transports associated with it which are directed equatorward in the Northern Hemisphere.

Full access
Arnold Gruber

Abstract

The wavenumber-frequency spectra of satellite-observed brightness have been examined for the period 1 February 1967 through 29 February 1968 for the latitude belt 20N to 20S. It was found that the quasi-stationary modes and low wavenumbers contain most of the power. The propagating wave activity was located primarily in the 5–15N latitude zone. Perturbations with periods of 12.5 days and wavenumber 5 and about 6 days and wavenumber 9 were prominent. These are consistent with Rossby waves and easterly waves. Since the propagating brightness spectra are due to propagating clouds, the results indicate a traveling heat source as being important in the generation and maintenance of those waves. There was no indication in the brightness spectra of periods and wavelengths consistent with Kelvin waves. However, a tropospheric heat source is not ruled out for those waves.

Full access