Relationship Between the Global Electric Circuit and Electrified Cloud Parameters at Diurnal, Seasonal and Interannual Timescales

Dating back to the early 1900’s, J.W. Whipple began to validate C.R. Wilson’s global electric circuit hypothesis using global thunderdays to correlate to the diurnal variation in the global electric circuit (GEC). This study applies 16+ years of precipitation feature (PF) data from the Tropical Rainfall Measuring Mission (TRMM), alongside 12 years of electric field measurements from Vostok, Antarctica, to further examine this relationship. This report provides a detailed picture of the joint diurnal and seasonal variation of the GEC, as well as the corresponding PF parameters that are thought to drive the circuit. By understanding the similarity and differences between the GEC and PF parameters in significantly more detail, we begin to unfold a more refined picture of the physical properties acting to charge and maintain the circuit. This study takes this a step further by analyzing the GEC during the two different El Nino Southern Oscillation (ENSO) phases. The results show significantly different electric field conditions during El Nino and La Nina periods, with significant enhancements in the electric field taking place between the months of January through April at 16-24 UTC in La Nina years. A very similar trend can be seen in the global PF parameters as well, indicating a strong relationship between the variations seen in the GEC and the variation of the global PF’s at diurnal, seasonal and interannual timescales.