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Frank J. Lucadamo and H. A. Panofsky

A paper published in 1948 suggested that there was a correlation of 0.62 between the wind on Jupiter (as indicated by the motion of the Great Red Spot) and mean zonal geostrophic winds at the surface of the earth. Observations since 1948, on the other hand, indicate a correlation of −0.12, suggesting that the original correlation was spurious, even though it appeared statistically significant according to standard tests.

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J. Allen Zak and H. A. Panofsky

Abstract

Ten-day average “thermal winds” derived from TIROS VII in the CO2 band are compared to the corresponding geostrophic winds at 10 mb at latitudes 40–60N. The correlations for the west-east components are of order 0.8, those for the south-north components, 0.5. Much of the correlation in the U components is due to concurrent seasonal trend.

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R. C. Curtis and H. A. Panofsky

Large-scale vertical velocities are shown to be closely related to the probabilities of convective precipitation and fair weather in the eastern United States during July 1955. In the daytime the mean relative humidity of the 900 to 700 mb layer is better related to the probability of convective precipitation than the vertical velocity. At night, however, vertical velocity is the best single predictor of convective precipitation, with a modified Showalter Index being a very useful additional criterion.

The large-scale vertical velocities that occur in normal summer synoptic situations appear to be produced by a diurnal variation in the momentum exchange between the ground and the air.

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Richard Lyons, H. A. Panofsky, and Sarah Wollaston

Abstract

It is shown that, in the lowest few hundred meters, nighttime inversions tend to break down due to onset of turbulence when the Richardson number falls between 0.2 and 0.5. Since the Richardson number is statistically related to the wind speed at one to a few hundred meters, it is found that the dew-point depression in the morning, as well as visibility, is related to the wind speed above the surface. It follows, that objective forecast techniques for the dew-point depression and visibility can be improved by including the wind speed above the surface as a parameter.

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H. L. Griffith, H. A. Panofsky, and I. Van der Hoven

Abstract

It is shown that a spectrum covering a large range of frequencies can be found by superposing estimates of spectra of means over periods of different lengths. The method is illustrated by the power spectrum of temperature at University Park, Pennsylvania, covering periods from 2 to 7300 days. The spectrum is characterized by a major peak at four days and several minor ones, the reality of which is uncertain.

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CHIN-HUA HUANG, H. A. PANOFSKY, and ARTHUR SCHWALB

Abstract

Various synoptic variables are related to satellite radiation data. It is shown that: (1) Vertical motion is related jointly to window radiation and water vapor radiation. (2) Surface relative humidity can be estimated from window radiation and cloud brightness. (3) Ceilings can be estimated from window radiation and cloud brightness.

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Hans A. Panofsky, John A. Dutton, Kurt H. Hemmerich, G. McCreary, and N. V. Loving

Abstract

Two separate case studies of clear air turbulence are presented, one in the stratosphere over the Rocky Mountains, the other in the upper troposphere over the midwestern plains.

The mechanism in both situations appears to be similar. CAT occurs in strongly baroclinic zones with strong vertical wind shears and low Richardson numbers. There is a tendency for the most severe turbulence to be located at the edges of the baroclinic zones.

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H. A. Panofsky and 1st Lt. Woodrow W. Dickey, A.C.
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