Wavenumber Spectra of Ozone from Gasp Aircraft Measurements

Abstract

Results from spectral analysis of ozone, wind, and temperature measurements collected during the Global Atmospheric Sampling Program (GASP) are presented. These data were taken with instruments placed aboard B747 airliners in routine commercial service. About 90 percent of these data fall in the altitude range 9–13 km and about 75 percent are from latitudes 30 to 60 degrees North. The variance power spectra span the wavelength range from about 100–104 km for wind and temperature and 10–2400 km for ozone. Variation with latitude and season and between the troposphere and stratosphere are presented. Results are interpreted in the framework of geostrophic turbulence theory at long wavelengths, and quasi-two-dimensional turbulence and internal gravity waves at wavelengths below about 300–500 km. Numerical examples are used to illustrate that the spectrum of ozone variations is consistent with a spectrum of vertical displacements acting on a background vertical gradient of ozone.