Diurnal Variation of Temperature in the Upper Stratosphere as Indicated by a Meteorological Rocket Experiment

Abstract

Fourteen HASP and two ARCAS rockets, carrying WOX-1A and Arcasonde 1A instrumentation, respectively, were launched at Wallops Island during a 39-hr period in September 1965 to gain information regarding 1) the daily variation of temperature and wind within the 30- to 50-km layer, and 2) the compatibility between temperatures measured nearly simultaneously by the rocketsondes and by supporting balloon-borne radiosondes. Analysis of the observed rocketsonde temperatures indicates a diurnal variation ranging from about 3C at 30 km to 9C at 48 km. Marked differences in the temperatures measured by rocketsondes launched prior and subsequent to sunrise and sunset suggest that a portion of the variation may not be real, but is possibly a, function of instrumental error. Support for this inference is provided by computations utilizing the rocketsonde winds as an independent means of determining the diurnal temperature wave. The results yield an amplitude about half that of the observed variation in the 35- to 45-km layer. Temperatures obtained from several rockets launched within a short time interval disclose that the HASP (WOX-1A) system is capable of reproducing a given temperature profile with relatively small random error. In addition, ARCAS (Arcasonde 1A) measurements appear compatible with those of the HASP. However, a definite discrepancy was found to exist between rocketsonde temperatures and these reported by the supporting rawinsonde observations. Additional experiments are suggested as a means of determining the errors inherent in measurement of temperature by the various systems.