Accession Number : AD0634154

Title :   TECHNIQUES FOR DETERMINING A WORLD-WIDE CLIMATOLOGY OF TURBULENCE THROUGH USE OF METEOROLOGICAL DATA.

Descriptive Note : Interim scientific rept.,

Corporate Author : STANFORD RESEARCH INST MENLO PARK CALIF

Personal Author(s) : Endlich, R. M. ; Mancuso,R. L. ; Davies,J. W.

Report Date : 04 MAY 1966

Pagination or Media Count : 65

Abstract : This report consists of an introductory portion followed by separate sections concerned with aircraft observations of jet-stream and mountain-wave turbulence, statistical relationships between airline pilots' reports of turbulence and concurrent meteorological conditions, and the feasibility of measuring turbulence from rising balloons tracked by FPS-16 missile-tracking radar. The aircraft data show that turbulence correlates well with the horizontal wind direction shear measured on the mesoscale. Recent aircraft data also re-emphasize the hazards to aircraft that exist in mountain-wave turbulence. A pictorial model of the mountain wave is presented showing the usual turbulent layers and other prominent features. A number of meteorological quantities were correlated with frequencies of turbulence determined from pilot reports. The product of vertical vector wind shear and horizontal resultant deformation gave a correlation of 0.45--the highest value found so far from data of this type. Contingency tables of turbulence frequency as a function of vertical shear and lapse rate indicate that lapse rate is not significant in the manner indicated by Richardson?s number. From meteorological data and empirical equations, expected frequencies of turbulence over the United States were computed and compared with observed frequencies. Reasonably good agreement was obtained, indicating that it is feasible to determine the climatology of turbulence from standard meteorological data. In the final section of the report, FPS-16 measurements of slant range, azimuth, and elevation of rising Jimsphere balloons are smoothed, and deviations from the smoothed curves are plotted as functions of time (or altitude). (Author)

Descriptors :   (*ALL WEATHER AVIATION, CLEAR AIR TURBULENCE), (*CLEAR AIR TURBULENCE, *CLIMATE), (*JET STREAMS, CLIMATE), CORRELATION TECHNIQUES, ATMOSPHERIC MOTION, MICROMETEOROLOGY, MOUNTAINS, METEOROLOGICAL PHENOMENA, ATMOSPHERIC SOUNDING, METEOROLOGICAL BALLOONS, CIVIL AVIATION, PILOTS

Subject Categories : Commercial and General Aviation
      Meteorology

Distribution Statement : APPROVED FOR PUBLIC RELEASE