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Estimates of requirements likely to be levied on a new observing system for mesoscale meteonology are given. Potential observing systems for mesoscale numerical weather prediction are discussed. Thermodynamic profiler radiometers, infrared radiometer atmospheric sounders, Doppler radar wind profilers and surveillance radar, and moisture profilers are among the instruments described.
Vertical profiles of High-resolution Doppler imager (HRDI) mesospheric winds have small-scale structure (vertical wavelengths between 10 and 20 km) that is virtually always present. Fourier analysis of HRDI zonal and meridional wind profiles have been carried out, and the spectral characteristics are sorted by latitude, month and local time. Power spectral density (PSD) exhibits a universal exp(-km) structure in the 10-20km wavelength regime, with K lying between 2 and 3. The observed PSD for wavelengths between 10 and 20 km is a factor of 3 higher than a null spectrum constructed from HRDI reported error bars multiplied by randomly varying numbers between -1 and +1. Stokes parameters were consolidated by month into Northern and Southern hemisphere middle and high latitudes belts (40-72 degrees), tidal belts (32-16 degrees) and a tropical belt (8S-8N). Vertical waves between 10 and 15 km in wavelength are about 10-15% polarized everywhere. The inferred propagation direction in the middle and high latitude Southern hemisphere is predominantly meridional during solstice, and significantly more zonal during equinoxes. In the tropical belt, the wave orientations are nearly North-South during solstices, with a slightly higher east-west component during equinox. In the tidal belts where the background wind includes a strong meridional tidal wind, the preferred wave orientation has a significant zonal component during equinox. These findings are consistent with the interpretation of wave filtering by the background wind.
An analysis is presented of high resolution wind profile measurements recorded at the NASA 150-m ground winds tower facility, showing wind speed shear frequency and magnitude distributions for six vertical layers of the atmosphere and one vertical distance. Vertical wind shear is defined as the change of wind speed with height, and its magnitudes were derived by algebraically subtracting lower level wind speeds from those of higher levels and dividing the distance between levels. Horizontal wind shear is understood to be change of wind speed with horizontal distance, and its magnitudes were derived by algebraically subtracting the wind speed at a short tower from that at a tall one and dividing by the distance between towers.
Selected atmospheric conditions observed near Space Shuttle STS-7 launch time on June 18, 1983, at Kennedy Space Center, Florida are summarized. Values of ambient pressure, temperature, moisture, ground winds, visual observations (cloud), and winds aloft are included. The sequence of prelaunch Jimsphere measured vertical wind profiles is given in this report. Also presented are wind and thermodynamic parameters representative of surface and aloft conditions in the SRB descent/impact ocean area. Final meteorological tapes, which consist of wind and thermodynamic parameters versus altitude, for STS-7 vehicle ascent and Acoustic/SRB descent have been constructed. The STS-7 ascent meteorological data tape has been constructed by Marshall Space Flight Center in response to Shuttle task agreement No. 936-53-22-368 with Johnson Space Center.
Ground-wind environments for Monte Carlo simulations of Space Shuttle liftoff at KSC are developed. Input parameters include randomly selected 18.3-m-altitude peak wind speed (from which mean wind profile and turbulence intensity are calculated), randomly selected mean wind direction, and longitudinal and lateral turbulence components obtained from the Shuttle-simulation turbulence tapes (SSTT: Tatom et al., 1982). The steps in the simulation of turbulence time histories and horizontal wind fields are listed. It is found that separate statistical analysis of each hour-season pair, applying data on the time fraction of occurrence of peak winds and wind directions at KSC, will be necessary to interpret simulation results consistently.
Selected atmospheric conditions that were observed near Space Shuttle STS-41G launch time on October 5, 1984 at Kennedy Space Center in Florida are summarized. Values of ambient pressure, temperature, moisture, ground winds, visual obsrvations (cloud), and winds aloft are included. The sequence of prelaunch Jimsphere-measured vertical wind profiles is given. The final atmospheric tape consisting of wind and thermodynamic parameters versus altitude for STS-41G vehicle ascent was constructed. The STS-41G ascent atmospheric data tape was constructed. The STS-41G ascent atmospheric data tape was constructed by Marshall Space Flight Center's Atmospheric Sciences Division to provide an internally consistent data set for use in post flight performance assessments.
Horizontal wind profile measurements recorded at the NASA 150-Meter Ground Winds Tower Facility at the Kennedy Space Center, Fla., are analyzed to evaluate wind shears known to be hazardous to the ascent and descent of conventional aircraft and the Space Shuttle. Twenty 5-s intervals of high (between 10 and 18 m/s) and gale force (18 to 33 m/s) surface winds provided instantaneous recordings every 0.1 s per speed, direction, and tower level from 3-150 m. Mathematical (maximum, mean, standard deviation) and graphical (percentage frequency distribution) descriptions of absolute, positive, and negative speed and direction shears with altitude (six vertical layers) and along flight path (one horizontal distance) are presented as functions of the intensity categories and significant values.
Since researchers couldn't prove that the mesospheric turbulence layers are generated by the simultaneously existing short-period gravity waves, they invoked other generation mechanisms than wave breaking. Possible mechanisms like lateral convection (Rottger 1980a), quasi-geostrophic flows at mesoscales (Lilly, 1983) or vortical modes of motion as seen in the ocean (Muller and Pujalet, 1984) could be candidates. Researchers are inclined to see a connection of these layers or laminae with very-long-period internal waves because of the periodicity in their vertical structure and their long mean persistency. Rottger (1980b) had proposed that such structures are due the modulation of the me an temperature and wind profiles by internal waves. The superposition of random or short-term wave-induced wind and temperature fluctuations with the background profile, modulated by very-long-period waves (quasi-inertia waves) then would yield the observed effects, and could explain the vertical periodicity, the long-term mean persistency as well as some short-term variability of their intensity.
Atmospheric wind profiles and boundary layer turbulence power spectra for calculation of wind loads on space vehicles during prelaunch and launch
A brief overview is provided of the coherent Doppler lidar work at the Marshall Space Flight Center, taking into account the status and planned development of the system to be used for severe storms research. The considered system is a CW Doppler lidar operating at a wavelength of 10.6 micrometers. This lidar uses a 20 watt carbon dioxide laser. It has a range which is continuously variable from 60 m to approximately 600 m. Range variation is achieved through changing the focus of a 30 cm f/2 Cassegrainian telescope. Successful measurements with the CW lidar have included two and three dimensional wind profiles, wing tip vortex tracks and profiles, dust devil tracks and profiles, and transverse as well as line-of-sight wind velocities. The pulsed lidar in recent ground tests has succeeded in measuring clear air returns to a range of 13 km and has provided substantial information on velocities associated with the gust fronts of thunderstorms.
This report presents a summary of selected atmospheric conditions observed near Space Shuttle STS-5 launch time on November 11, 1982, at Kennedy Space Center, Florida. Values of ambient pressure, temperature, moisture, ground winds, visual observations (cloud), and winds aloft are included. The sequence of prelaunch Jimsphere measured vertical wind profiles is given in this report. Also presented are the wind and thermodynamic parameters measured at the surface and aloft in he SRB descent/impact ocean area. Final meteorological tapes, which consist of wind and thermodynamic parameters versus altitude, for STS-5 vehicle ascent and SRB descent have been constructed. The STS-5 ascent meteorological data tape has been constructed by Marshall Space Flight Center in response to Shuttle task agreement No. 936-53-22-368 with Johnson Space Center.
Selected atmospheric conditions observed near Space Shuttle STS-13 launch time on April 6, 1984, at Kennedy Space Center Florida are summarized. Values of ambient pressure, temperature, moisture, ground winds, visual observations (cloud), and winds aloft are included. The sequence of prelaunch Jimsphere measured vertical wind profiles is given. The final meteorological tape, which consists of wind and thermodynamic parameters versus altitude, for STS-13 vehicle ascent was constructed by Marshall Space Flight Center in response to shuttle task agreement No. 561-81-22-368 with Johnson Space Center.
Selected atmospheric conditions observed near Space Shuttle STS-51A launch time on November 8, 1984, are summarized. Values of ambient pressure, temperature, moisture, ground winds, visual observations (cloud), and winds aloft are included. The sequence of prelaunch Jimsphere measured vertical wind profiles is reported. The final atmospheric tape, which consists of wind and thermodynamic parameters versus altitude, for STS-51A vehicle ascent was constructed. The STS-51A ascent atmospheric data tape is constructed to provide an internally consistent data set for use in postflight performance assessments.
Selected atmospheric conditions observed near space shuttle STS-51C launch time on January 24, 1985, at Kennedy Space Center, Florida are summarized. Values of ambient pressure, temperature, moisture, ground winds, visual observations (cloud), and winds aloft are included. The sequence of prelaunch Jimsphere measured vertical wind profiles are presented. The final atmospheric tape, which consists of wind and thermodynamic parameters versus altitude, for STS-51C vehicle ascent was constructed. The STS-51C ascent atmospheric data tape was constructed to provide an internally consistent data set for use in postflight performance assessments.
A summary of selected atmospheric conditions observed near space shuttle STS-51B launch time on April 29, 1985, at Kennedy Space Center Florida is presented. Values of ambient pressure, temperature, moisture, ground winds, visual observations (cloud), and winds aloft are included. The sequence of prelaunch Jimsphere measured vertical wind profiles is given. The final atmospheric tape, which consists of wind and thermodynamic parameters versus altitude, for STS-51B vehicle ascent was constructed. The STS-51B ascent atmospheric data tape was constructed by Marshall Space Flight Center's Atmospheric Sciences Division to provide an internally consistent data set for use in post flight performance assessments.
A summary is given of selected atmospheric conditions observed near Space Shuttle STS-51L launch time on January 28, 1986, at Kennedy Space Center, Florida. Values of ambient pressure, temperature, moisture, ground winds, visual observations (cloud), and winds aloft are included. The sequence of pre-launch Jimsphere measured vertical wind profiles is given. The final atmospheric tape, which consists of wind and thermodynamic parameters versus altitude, for STS-51L vehicle ascent has been constructed. The STS-51L ascent atmospheric data tape has been constructed by Marshall Space Flight Center's Atmospheric Sciences Division to provide an internally consistent data set for use in post flight performance assessments.
A summary of selected atmospheric conditions observed near Space Shuttle STS-26 launch time on September 29, 1988, at Kennedy Space Center, Florida is given. Values of ambient pressure, temperature, moisture, ground winds, visual observations (cloud), and winds aloft are included. The sequence of pre-launch Jimsphere measured vertical wind profiles is given. The final atmospheric tape, which consists of wind and thermodynamic parameters versus altitude, for STS-26 vehicle ascent has been constructed. The STS-26 ascent atmospheric data tape has been constructed by Marshall Space Flight Center's Earth Science and Applications Division to provide an internally consistent data set for use in post-flight performance assessments.
Selected articles on atmospheric conditions observed near Space Shuttle STS-27 launch time on December 2, 1988, at Kennedy Space Center, Florida are summarized. STS-27 carried a Department of Defense payload and the flight azimuth in this report will be denoted by reference flight azimuth, since the actual flight azimuth is not known. Values of ambient pressure, temperature, moisture, ground winds, visual observations (cloud), and winds aloft are included. The sequence of pre-launch Jimsphere-measured vertical wind profiles is given. The final atmospheric tape, which consists of wind and thermodynamic parameters versus altitude, for STS-27 vehicle ascent was constructed. The STS-27 ascent atmospheric data tape was constructed by Marshall Space Flight Center's Earth Science and Applications Division to provide an internally consistent data set for use in post-flight performance assessments.