A Study of the African 'Chimney' Region with Schumann Resonance Methods

这笔赠款支持在全球几个地点对舒曼共振观测的解释进行持续研究。地球表面及其周围的电离层构成了一个球形电容器，作为极低频率电磁波的谐振腔。基模的幅度(约8赫兹)与世界范围内的闪电活动有关。对给定位置的舒曼共振(SR)的观测揭示了一个背景信号，其上是由强烈雷暴引起的叠加瞬变。全球闪电活动的三个主要区域是热带非洲、热带南美洲和印度尼西亚。这项研究的重点是第一个区域的闪电，即非洲对流或“烟囱”区域。在罗德岛的SR野外观测站的观测表明，非洲上空的闪电活动有四到五天的周期。对这种周期性的两种可能的解释是非洲东风波或全球5天波。该计划的一个目标是分析SR数据和来自卫星、降雨观测和全球天气图的辅助观测，以确定周期性的原因。另一个目标是解释闪电在非洲大陆上空具有正极性，而在大西洋近海具有负极性的明显趋势。

This grant supports continuing research on the interpretation of Schumann Resonance observations at several sites around the globe. The surface of the planet Earth and the ionosphere that surrounds it constitute a spherical capacitor, which serves as a resonant cavity for extremely low-frequency electromagnetic waves. The amplitude of the fundamental mode (about 8 Hz) is related to world-wide lightning activity. Observations of the Schumann Resonances (SR) at a given location reveal a background signal on which are superimposed transients caused by intense thunderstorms. The three main regions of global lightning activity are tropical Africa, tropical South America, and Indonesia. This work focuses on lightning in the first of these regions, the African convective or "chimney" zone. Observations at the SR field station in Rhode Island indicate a four-to-five day periodicity in lightning activity over Africa. Two possible explanations of this periodicity are African easterly waves or the global 5-day wave. One objective of the program is to analyze the SR data and supporting observations from satellites, rainfall observations, and global weather maps, to determine the cause of the periodicity. Another objective is to explain the apparent tendency for lightning to have positive polarity over the African continent and negative polarity offshore over the Atlantic Ocean.