The probability density distribution of the speed, horizontal shear and vertical shear of the zonal-mean wind are computed. The speed of the zonal wind is found to have a probability density distribution that is unimodal both within the zone of the largest planetary wave amplitude (45-70 N) and when averaged over the entire midlatitudes (25-75 N). Unimodal distributions are also found for both the N-S shear of the zonal mean wind and the vertical shear of the zonal mean flow between 300 and 850 mb. Lagged correlations between the zonal mean wind parameters and the wavenumber 2-4 amplitude are computed and found to be small at all lags. This suggests that the temporal variability of the planetary waves in the midlatitudes of the troposphere is not directly connected to the variability in the strength or shear of the zonal mean flow.
THE PROBABILITY DENSITY DISTRIBUTION OF THE SPEED AND HORIZONTAL AND VERTICAL SHEAR OF THE ZONAL-MEAN FLOW / Hansen, Ar; Sutera, Alfonso. - In: JOURNAL OF THE ATMOSPHERIC SCIENCES. - ISSN 0022-4928. - 44:11(1987), pp. 1525-1533. [10.1175/1520-0469(1987)044<1525:TPDDOT>2.0.CO;2]
THE PROBABILITY DENSITY DISTRIBUTION OF THE SPEED AND HORIZONTAL AND VERTICAL SHEAR OF THE ZONAL-MEAN FLOW
SUTERA, Alfonso
1987
Abstract
The probability density distribution of the speed, horizontal shear and vertical shear of the zonal-mean wind are computed. The speed of the zonal wind is found to have a probability density distribution that is unimodal both within the zone of the largest planetary wave amplitude (45-70 N) and when averaged over the entire midlatitudes (25-75 N). Unimodal distributions are also found for both the N-S shear of the zonal mean wind and the vertical shear of the zonal mean flow between 300 and 850 mb. Lagged correlations between the zonal mean wind parameters and the wavenumber 2-4 amplitude are computed and found to be small at all lags. This suggests that the temporal variability of the planetary waves in the midlatitudes of the troposphere is not directly connected to the variability in the strength or shear of the zonal mean flow.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.