Research

Research projects within the USGS Geomagnetism Program are targeted for societal relevance, especially for space-weather hazard science. Consistent with the goals and issues addressed in the USGS Natural Hazards Strategic Plan, these research projects support:

1. pursuit of fundamental understanding of geomagnetic storms and related phenomena
2. development of geomagnetic products needed for assessments and real-time situational awareness
3. informed operation of the Program's magnetic-observatory network

Geomagnetism Program research staff provide outside advice, national and international leadership, and write educational articles about geomagnetic and space-weather hazards.

Fundamental research within the USGS Geomagnetism Program is concentrated on the analysis of the information content of magnetic-field time series acquired at ground-base magnetic observatories. Methods include formal time-series and statistical analysis, and data assimilation for physics-based models of the magnetosphere and ionosphere. Recent work has included the analysis of the symmetry (and asymmetry) of low-latitude ground-level magnetic disturbance during individual magnetic storms; long-term secular change in geomagnetic disturbance and its correlational relationship with sunspots and interplanetary solar wind; secular change in geomagnetic activity and global climate change; solar-quiet geomagnetic variation and periodic geomagnetic tides; extreme-geophysical-event analysis; and investigation of claims that earthquakes are sometimes preceded by magnetic precursory signals.

Guided by fundamental understanding, geomagnetic products are developed to meet the needs of the space-weather community for hazard assessments and real-time situational awareness. Recent work has concentrated on the development of new and improved summary-index measures of global magnetic disturbance related to the magnetospheric ring current and the auroral electrojet, needed for validating and as input for physics-based models of the space environment; and localized measures of magnetic disturbance and geomagnetically-induced currents needed by the electric power-grid industry. The Geomagnetism Program recently initiated a project for estimating geomagnetically-induced currents in the lithosphere in order to assess and mitigate hazards for the power-grid industry.