Relationships among the surface wind, horizontal synoptic-scale
pressure gradient and topography are studied in the Willamette Valley
in western Oregon. Terrain features alter the standard surface wind-pressure
gradient relationship such that the angle between the surface
wind and the surface geostrophic wind is most frequently 60°.
In winter the surface...
Surface meteorological data collected at a mesonetwork in
Colorado during the 1973 National Hail Research Experiment were
analyzed to see if a diurnal oscillation of boundary layer wind exists
and also to determine the mechanism that drives the wind system.
The average temperature, pressure, and wind velocity for a month's...
High resolution data of moisture, temperature and wind velocity
collected by aircraft during the 1975 Air Mass Transformation
Experiment (ANTEX '75) provide information for detailed investigations
of the phenomena occurring at the top of a cloud-topped mixed
layer.
Joint frequency diagrams of humidity and temperature reveal that
for parts of...
A method of calculating surface evapotranspiration by separately
including the effects of vegetation and atmospheric evaporative demand
under the condition of nonlimiting soil moisture is presented. A
literature survey is conducted to determine the effects of plants on
evapotranspiration.
To represent the atmospheric evaporative demand, the original
potential evaporation equation...
An analytical two-layer model consisting of a time-dependent stratified
boundary layer topped by stratified free flow is developed in order
to study atmospheric boundary layer production of vertical motion. To
avoid use of a constant eddy viscosity, the boundary layer equations are
layer-integrated over a fixed depth, and surface stress...
In plume theory it is generally assumed that a plume issuing from a round source maintains a round cross section throughout. The consequences of this hypothesis are significant; this fact should motivate research into its validity. This paper investigates conditions and analyzes mechanisms that cause fluid plumes to undergo systematic...
The stability of steady-state solutions of the equations governing two-dimensional,
homogeneous, incompressible fluid flow are analyzed in the context
of shear-flow in a channel. Both the linear and nonlinear theories are
reviewed and compared. In proving nonlinear stability of an equilibrium,
emphasis is placed on using the stability algorithm developed...
Several horizontal flight segments from SESAME and
ALPEX are studied using structure functions and specral
analysis methods. Theoretical analysis of the relative
errors in structure function and correlation function in
the presence of large scale wave activity is presented. The
effect of stratification and shear on the -5/3 inertial
subrange...
An eigenvector analysis of the velocity-temperature correlation
matrix is applied to clear-air turbulence measured by aircraft in the
Bora. The eigenvectors are identified with the main eddies of the
turbulence. This study attempts to infer the three-dimensional
structure of these eddies. The results are compared with turbulent
structures in the...
A two-scale approach for the turbulent mixing of momentum in an unstable stratified boundary layer is proposed in an attempt to eliminate existing inconsistencies between parameterized mixing of heat and momentum. The parameterization of the large eddy stress is suitable for simple boundary layer models where computational efficiency is important....