The object of this work is the measurement of lightning activity on a global scale through its excitation of the electromagnetic resonances of the global electrical circuit. Local measurements in the tropics have shown that lightning activity is sensitively dependent on the wet bulb temperature of boundary layer air. The PIs propose to make detailed comparisons between Schumann resonance amplitudes and the real distributions of wet bulb temperature and deep tropical convection. Feedback effects of the deep convection in the temperature distributions and subsequent global lightning will be examined. A new station in Peru will compliment two existing ones in California and Western Australia. Comparisons will be made with independent measurements of the ionospheric potential and observations of ionization of the ionosphere. The project will include investigation of possible ELF electromagnetic signatures of upward propagating cloud-ionosphere discharges originating in Amazonian thunderstorms. The practical importance of this research lies in its potential for developing a sensitive index of global change from easily obtainable ground- based measurements of Schumann resonances.
