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Scoggins, J. R.

Publications and source records attributed to Scoggins, J. R..

At least 55 records · Page 3

The importance of the curvature of the wind profile in determining regions of CAT and non-CAT

An investigation is conducted regarding the relationship between CAT and the curvature of the wind profile, taking into account cases of CAT encountered by the XB-70 in the stratosphere over the mountainous terrain of the western U.S. The results of the investigation show that the curvature of the wind profile is an important tropospheric variable in the determination of stratospheric CAT regions. These CAT regions are likely to occur in cases in which the curvature increases with height in the troposphere in areas when mountain waves are expected.

Possiel, N.↗

Distinguishing between CAT and non-CAT areas by use of discriminant function analysis

The investigation considered is concerned with a method in which a statistical approach is employed to determine algebraic functions involving selected synoptic-scale parameters which would indicate areas and altitudes of CAT in the stratosphere over the western U.S. The statistical approach selected is based on discriminant function analysis. The functions are determined from combinations of synoptic-scale parameters and stratospheric turbulence data. It was found in the investigation that there is a relationship between selected combinations of synoptic-scale parameters of the upper troposphere and lower stratosphere and stratospheric clear-air turbulence.

Clark, T. L.↗

Data for first NASA Atmospheric Variability Experiment (AVE 1). Part 1: Data tabulation

A tablulation is given of rawinsonde data for NASA's first Atmospheric Variability Experiment (AVE 1) conducted during the period February 19-22, 1964. Methods of data handling and processing, and estimates of error magnitudes are also given. Data taken on the AVE 1 project in 1964 enabled an analysis of a large sector of the eastern United States on a fine resolution time scale. This experiment was run in February 1964, and data were collected as a wave developed in the East Gulf on a frontal system which extended through the eastern part of the United States. The primary objective of AVE 1 was to investigate the variability of parameters in space and over time intervals of three hours, and to integrate the results into NASA programs which require this type of information. The results presented are those from one approach, and represent only a portion of the total research effort that can be accomplished.

Scoggins, J. R.↗

A compilation of studies from Atmospheric Variability Experiment (AVE)

Five methods for obtaining the sign of vertical motion at various levels in the atmosphere were investigated to determine which gave the best explanation for areas of rain and no-rain in the southeastern United States during the period February 19-22, 1964. The methods used were the terrain-induced vertical motion, the kinematic method including the terrain effect, the adiabatic method, the omega equation, and the vorticity equation combined with Dines' Compensation Principle. Stability and moisture availability were considered but not as extensively as vertical motion. Values of vertical motion obtained by the kinetic method, including orographic lifting produced the best agreement with the observed areas. When terms in the omega equation were added through use of constant multipliers, results comparable to the adiabatic method were obtained. Without this addition large uncertainties occurred. Maps showing areas where terms of the omega equation would indicate positive vertical motion did not correlate well with the observed rainfall patterns.

Scoggins, J. R.↗

Mountain waves and CAT encountered by the XB-70 in the stratosphere.

The data from 36 XB-70 flights conducted over the mountainous regions of the western United States together with rawinsonde data were used to investigate relationships between conditions favorable for mountain waves and clear air turbulence. Profiles for the Scorer parameter and the gradient Richardson number were evaluated from the rawinsonde data. The Scorer parameter and the gradient Richardson number profiles were computed on those days when the XB-70 flew, and these results compared to model profiles and related to the reported turbulence. Ascent rate profiles of rawinsonde balloons were analyzed from which the presence of mountain or lee waves was inferred.

Scoggins, J. R.↗

An investigation of relationships between meso- and synoptic-scale phenomena

Methods based on the vorticity equation, the adiabatic method, the curvature of the vertical wind profile, and the structure of synoptic waves are used to determine areas of positive vertical motion in the mid-troposphere for a period in each season. Parameters indicative of low-level moisture and conditional instability are areas in which mesoscale systems may be present. The best association between mesoscale and synoptic-scale phenomena was found for a period during December when synoptic-scale systems were well developed. A good association between meso- and synoptic-scale events also was found for a period during March, while the poorest association was found for a June period. Daytime surface heating apparently is an important factor in the formation of mesoscale systems during the summer. It is concluded that the formation of mesoscale phenomena may be determined essentially from synoptic-scale conditions during winter, late fall, and early spring.

Scoggins, J. R.↗

Meteorological parameters versus CAT encountered in the stratosphere by the XB-70 airplane.

Frequency distributions prepared from synoptic meteorological parameters associated with turbulent and nonturbulent conditions encountered by the XB-70 aircraft at altitudes generally between 12 and 20 km in the stratosphere show that turbulence is associated with certain ranges or critical values of the parameters. Certain combinations of the variables are associated with turbulence for at least one-fourth to one-third of the observations.

Scoggins, J. R.↗

How some nonmeteorological professionals view meteorology and weather forecasting.

The results of a questionnaire designed to gather information on how nonmeteorological scientists and engineers view meteorology and weather forecasting are summarized in this paper. The respondents were from two organizations, Texas A & M University and NASA's Marshall Space Flight Center, the first representing the academic community and the latter the engineering community. While there were some differences between the groups, in most cases answers expressed in the opinionnaire by the two groups were essentially identical. The results revealed the following: Approximately three-fourths of the respondents use meteorological data and/or weather forecasts in their profession; the meaning of probability forecasts is very unclear with only 13% indicating the correct answer; television is the main source of weather information; approximately half of the respondents had never heard of the Global Atmospheric Research Program; and the opinion was almost unanimous that satellites had contributed significantly to weather observations and/or forecasts. Also, the results indicated a number of other ?problem' areas where some improvements are desired.

Scoggins, J. R.↗

The wind field

Statistical properties of wind field for launch vehicle design

Scoggins, J. R.↗

The wind field

Wind field statistical properties using model incorporating quasi-steady state speed, shear, gusts and small scale motions

Scoggins, J. R.↗