Turbulent diffusivities and energy dissipation rates in the stratosphere from GOMOS satellite stellar scintillation measurements

Abstract

Abstract. Parameters of anisotropic and isotropic spectra of refractivity, density and temperature perturbations obtained from GOMOS satellite measurements of stellar scintillations are used to estimate turbulent Thorpe scales, LT, diffusivities, K, and energy dissipation rates, ε, in the stratosphere. At low latitudes, average values for altitudes 30–45 km in September–November 2004 are LT~1–1.1 m, ε~(1.8–2.4)×10−5 W kg−1, and K ~ (1.2–1.6) × 10−2 m2 s−1 depending on different assumed values of parameters of anisotropic and isotropic spectra. Respective standard deviations of individual values including all kinds of variability are δLT ~ 0.6–0.7 m, δε ~(2.3–3.5)×10−5 W kg−1, and δK ~ (1.7–2.6)×10−2 m2 s−1. These values correspond to high-resolution balloon measurements of turbulent characteristics in the stratosphere, and to previous satellite stellar scintillation measurements. Distributions of turbulent characteristics at altitudes 30–45 km in low latitudes have maxima at longitudes 30–100° W, 0–60° E and 90–180° E, which correspond to continent locations. Correlations between parameters of anisotropic and isotropic spectra are studied.