Universal spectra of electric field pulsations in the atmosphere

Abstract

Short-term (f ≃ 10-3-1 Hz) electric field pulsations in the surface atmospheric layer have been measured during 1999-2001 under the fair-weather and fog conditions. At the frequencies of 10-2-1 Hz these pulsations have a power-law spectrum with the spectral index varying in the range from -1.23 to -3.36 while the most probable values of the index fall into the range from -2.25 to -3.0, unlike the temperature fluctuation spectra which obey in the inertial subrange the Kolmogorov power law with the spectral index close to -5/3. Under the fog conditions the intensity of electric-field pulsations increases by about an order of magnitude compared to the fair-weather conditions. The relation of spectral characteristics to the formation of aero-electric structures (AESs) is evident; the spectral index distribution during AES flyby has two maxima. Analysis of the mechanisms explains the relationship between electric-field spectra and the neutral-gas turbulence and AES formation.