Aircraft Investigation of the Turbulent Transport of Electric Charge through the Unstable Planetary Boundary Layer

摘要

Experimental results from a two year aircraft investigation of the atmospheric electrical and meteorological properties of the unstable planetary boundary layer (PBL) are reported. The primary objectives of the research were to 1) examine the strength of the electrode effect charge source over land and sea, and 2) obtain simultaneous measurements of meteorological and charge fluxes under varying conditions of atmospheric stability to test predictions of a second order closure model of charge transport. Soundings of electric field, conductivity, temperature, condensation nuclei, dew point, and turbulence structure functions for velocity, temperature and humidity along with surface temperatures and wind speeds were obtained over the desert in southeastern New Mexico in May 1986, and over water in the Bahamas in March 1987. Our results indicate 1) strong electrode layers form over the ocean but are often inhibited over land by surface radioactivity and 2) the shape and intensity of convection current profiles are dependent on electrical relaxation and turbulence intensity as predicted by the charge transport model. Keywords: Atmospheric electricity; Electrode layer; Convection current; Turbulent charge transport. (JHD)