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Schmidlin, F. J.

Publications and source records attributed to Schmidlin, F. J..

104 records · Page 6
All sourcesNASA NTRSDOE OSTI
NASA NTRS1980

Results of the August 1977 Soviet and American meterological rocketsonde intercomparison held at Wallops Island, Virginia

A coordinated program of rocketsonde investigations along about 60 deg E and 70 deg W between the United States and U.S.S.R. is discussed. The rocketsonde instruments used by the U.S. and U.S.S.R. were compared and the results are presented. The U.S. Super Loki Datasonde and the U.S.S.R. M100B rocketsonde are discussed. Results indicate that the U.S/U.S.S.R. rocketsonde measurement agreement improved since the 1973 intercomparisons. It was learned that the mean of the differences of the temperatures compare to within 6 C at about 60 km and to within 2 C near 50 km. Wind measurements were also found to agree.

Schmidlin, F. J.↗
NASA NTRS1979

Balloon-borne ozonesonde and rocket temperature and wind data gathered during the July 1977 intertropical convergence zone experiment

In middle latitudes, it is possible for large concentrations of stratospheric air to be brought down to the tropopause through folds or breaks in the tropopause. The exchange of air from the tropopause into higher altitudes is not well understood. Thus, the ITCZ (Intertropical Convergence Zone) experiment, conducted from July 16 through July 31, 1977, included a series of balloon-borne ozone soundings. The results of these soundings are presented and explain in the vertical exchange of air and provide information on the short vertical scales-of-motion. Rocketsonde data was also gathered in the ITCZ experiment in support of a stratospheric scales-of-motion study. The investigation was to determine whether rocketsonde and satellite information currently used yield information on the stratospheric horizontal wave spectrum and its importance with respect to tropospheric and mesospheric interaction and transport.

Schmidlin, F. J.↗
NASA NTRS1979

Horizontal eddy diffusivities in the Northern Hemispheric stratosphere and lower mesosphere

Meteorological rocket soundings, launched between 1969-74 at six locations representative of low, middle, and high altitudes, are employed with the use of the statistical theory of diffusion, to determine the zonal and meridional component of eddy diffusivity between 30 and 55 km as a function of season, latitude, and altitude. A comparison is also made between annually-averaged eddy diffusivities above and below 30 km. It is shown that the zonal component of eddy diffusivity is approximately three to five times as large as the meridional component, in most cases. Both components of eddy diffusivity vary greatly with season, latitude, and altitude. Highest eddy diffusivities, found in the vicinity of the winter westerly jet, are approximately one order of magnitude higher than those present during the summer. Tropical eddy diffusivities, however, remain relatively small throughout the year. Annually, a minimum is indicated near 25 km between maximums located at the stratopause and tropopause.

Kao, S. K.↗
NASA NTRS1978

Preliminary results of the US-USSR meteorological rocketsonde intercomparison held at Wallops Island, VA - August 1977

The reported intercomparison tests were conducted in connection with the objective to make U.S. and USSR rocketsonde temperature data, obtained in studies of the stratosphere and lower mesosphere, compatible with each other. The tests were successful. In general, temperature and wind profiles from the M100B and Datasonde instruments exhibited many similarities up to the vicinity of the stratopause. Mean temperature differences for the day and night pairs are less than 5 C up to 50 km. The differences progressively increase to about 14-15 C at 70 km, with the M100B temperatures colder than the Datasonde data. The reasonably close similarity between the day and night temperature differences suggests that consistent radiation corrections are being applied to both systems. The agreement of the wind measurements below 58 km is a significant improvement compared to the 1973 comparisons when agreement only extended up to 45 km.

Schmidlin, F. J.↗
NASA NTRS1978

Comparisons of the in-situ measurements from the rocket Nimbus satellite comparison series II

Atmospheric measurements between 30 and 90 km using two rocket-borne techniques - the inflatable falling sphere and the acoustic grenade - are compared in order to determine temperature measurement compatibility. The falling sphere, deployed at 115 km, is tracked by precision radar to determine winds as well as accurate drag parameters needed to deduce density from which temperatures are derived. The acoustic grenade technique uses sound arrivals at the ground from grenades ejected at 2-km intervals to determine temperature and wind between 40 and 90 km. The available data were obtained during an in-situ techniques-comparison with the remote sounders aboard Nimbus 6 during the summer and winter of 1975.

Olsen, R. O.↗
NASA NTRS1978

Determination of eddy diffusivity in the stratosphere and mesosphere with the use of meteorological rocket data

Meteorological rocket soundings, launched between 1969-74 at six locations representative of low, middle, and high altitudes, are employed with the use of the statistical theory of diffusion, to determine the zonal and meridional component of eddy diffusivity between 30 and 55 km as a function of season, latitude, and altitude. A comparison is also made between annually-averaged eddy diffusivities above and below 30 km. It is shown that the zonal component of eddy diffusivity is approximately three to five times as large as the meridional component, in most cases. Highest eddy diffusivities found in the vicinity of the winter westerly jet are approximately one order of magnitude higher than those present during the summer. Tropical eddy diffusivities, however, remain relatively small throughout the year. Annually, a minimum is indicated near 25 km between maximums located at the stratopause and tropopause.

Kao, S. K.↗
NASA NTRS1977

Atmospheric thermal structure during a winter anomaly absorption event

Temperature and wind profiles between 60 and 90 km were obtained during an anomalous wintertime absorption event. Data were collected by passive inflatable falling spheres deployed from meteorological rockets. The enhanced radio wave absorption is apparently associated with a well-defined mesopause near 84 km and a large inversion near 68 km; these readings suggest that both phenomena have been displaced to a level about 5 km lower than normal. In addition, colder than normal temperatures are recorded in the 55 to 72 km range during the anomalous conditions. The possible relationship between this change in the mesospheric temperature structure and the anomalous absorption and atmospheric radiative characteristics is discussed.

Olsen, R. O.↗
NASA NTRS1977

Rocketsonde repeatability of temperature and wind measurements as obtained from rocketsonde network systems

Variability of temperature and wind data obtained close in time is of particular concern since questions exist on whether this variability is due to natural atmospheric variability or arises from instrumental causes. Previously conducted repeatability tests of the U.S. Loki Datasonde instrument indicated rms differences of 1C in temperature and 3 mps in wind. The newer Super Loki Datasonde instrument reaches apogee 20 km higher (about 82 km) than the older system and attains a higher initial fall velocity, thus the heat exchange effects on the measuring components are different. Data were obtained from routine rocketsonde launchings, available in pairs, with time differences of 12 to 120 minutes. Mean values calculated over the altitude range of 30 to 70 km indicate than an rms difference of 1-2 C in temperature and of 3-4 mps in the zonal and meridional components exist. Additional computations in 5-km altitude layers suggest that rms differences do not exceed 3 C and 7 mps at the highest altitudes.

Schmidlin, F. J.↗
NASA NTRS1975

Compatibility of meteorological rocketsonde data as indicated by international comparison tests

Results of two experiments involving intercomparisons of rocketsonde measurements of temperature and wind data in the 25 to 80 km altitude region in the CIMO (Commission for Instruments and Methods of Observations) program during September 1973 are reported. Rocketsonde systems used by France, the USSR, the UK, the U.S., and Japan in the two parts of the program (one series of tests at Wallops Island, Va., the other in French Guiana) are described. Wind data were derived from radar tracking of retardation devices and payloads in descent. Day and night temperature differences were examined. The intercomparisons revealed excellent compatibility of the rocketsonde data up to 60 km in wind observations. Some outstanding problems are pointed out.

Finger, F. G.↗
NASA NTRS1975

Diurnal experiment data report, 19-20 March 1974

Temperature and wind data are presented from 70 small meteorological sounding rockets launched from eight selected launch sites in the Western Hemisphere. Table 1 gives a complete listing of the launch sites involved and the altitude of temperature and wind observations successfully completed.

Schmidlin, F. J.↗