# Accession Number:

## AD0716361

# Title:

## Turbulence Characteristics over Heterogeneous Terrain.

# Descriptive Note:

## Final rept.,

# Corporate Author:

## PENNSYLVANIA STATE UNIV UNIVERSITY PARK

# Personal Author(s):

# Report Date:

## 1970-09-01

# Pagination or Media Count:

## 89.0

# Abstract:

The report summarizes some results from three separate field studies, in the United States and Norway. These conclusions are reached The Bradshaw-Peterson hypothesis that the ratio of the standard deviation of velocity components to the friction velocity is a universal function of Richardson number even when the air is not in equilibrium appears to be correct in the case of the standard deviation of vertical velocity. In that case, the ratio is approximately 1.3 in neutral air. For the horizontal velocity components, the hypothesis is only approximately true these components have low-frequency, mesoscale contributions which obey neither Monin-Obukhov similarity nor the above-named hypothesis. The hypothesis that the ratio between dissipation and friction velocity cube over height also has a general value in neutral air appears to be correct. The value is about the reciprocal of von Karmans constant. Spectra of vertical motion, multiplied by wave number and normalized by the variance or the square of friction velocity, have universal shapes, depending only on Richardson number in stable air. Author

# Descriptors:

# Subject Categories:

- Atmospheric Physics