Abstract: The rapid advancement of Earth and space exploration technologies has significantly enhanced studies of the global atmospheric electric circuit (GEC) through satellite-based lightning observations, ground-based monitoring networks, and optical emission measurements between clouds and the ionosphere. This paper analyzes the interaction mechanisms between electric currents across different atmospheric layers and various generators within the GEC system. We examine the influences of aerosols and cosmic rays on GEC dynamics, explore its coupling with climate change mechanisms, and investigate its interactions within solar-terrestrial relationships. Furthermore, we outline emerging trends in global atmospheric electric field research and environmental applications.The global atmospheric electric field model provides a fundamental theoretical framework for understanding multi-sphere coupling processes on Earth, offering significant scientific value for space weather prediction, meteorological phenomena interpretation, and geological process analysis. An integrated multi-platform observation network - comprising satellites, aerostats, unmanned aerial systems, aerial remote sensing platforms, and ground-based monitoring stations - enables comprehensive three-dimensional dynamic monitoring of global atmospheric electric fields.From a physical mechanism perspective, measurable anomalies in the global atmospheric electric field demonstrate correlations with: (1) solar activity variations, (2) thunderstorm electrification processes, and (3) characteristic negative anomalies preceding seismic events. The atmospheric ionization processes induced by radon gas emissions have been identified as potentially critical indicators for short-term earthquake forecasting. These findings suggest substantial application potential for global atmospheric electric field research in aerospace safety systems, advanced meteorological studies, and solar-terrestrial interaction investigations.