This study determines the relationship between intraseasonal oscillations in two independent measures of global lightning activity: a convective index derived from the GLA TOVS cloud data, and Schumann resonance (SR) magnetic intensity recorded at Arrival Heights, Antarctica. 7 years (1989-1995) of daily records were used. Results of composite and correlation analysis show that the intraseasonal wave in deep convection has a wave number one structure with the region from 120W to 60E having one phase, while the other hemisphere has the opposite phase. The signal in Schumann resonance is enhanced when deep convection is enhanced in the former hemisphere that comprises the main lightning-producing regions of South America and Africa. Conversely, the SR signal is suppressed when the convection propagates eastwards to the Indian and West Pacific Ocean. This relationship between deep convection and Schumann resonance intensity was best defined during the NH Springs of 1990 and 1992, but was less evident in 1993 and 1994