Geomagnetic Disturbance Data

​​​​​​NERC’s GMD data collection program supports ongoing research and analysis of GMD risk. GMD events are caused by the ejection of charged material from the sun and the interaction of this material with space around the earth (atmosphere and magnetosphere). The resulting disturbances in earth’s magnetic field have the potential to disrupt operations or cause damage to critical infrastructure, including power systems. Extremely strong GMD events, though rare, can induce strong quasi-dc currents in the electric power grid that could affect system voltages, relay and protection system performance, and the operation and health of some large power transformers.

Through the GMD data collection program, NERC is collecting GIC and magnetometer data from reporting entities for designated strong GMD events (Kp = 7 and greater). As specified in FERC Order No. 830, NERC will make collected GIC and magnetometer data available to support ongoing research and analysis.

For more information about GMD, please contact

Click here to report GMD Data: GMD Reporting Application

 GMD News

On October 1, 2020, the GMD Reporting Application was released and is available for reporting.

April 2021 - The GMD User Guide has been updated. To view the updated version, click here.

collapse Display Location : Key GMD Documents ‎(1)
GMD_Nothing_to_Report.pdfSection 1600 Confirmation for No GMD Equipment
collapse Display Location : Reporting Instructions ‎(1)
GMD_Data_Reporting_Instruction.pdfGMD Data Reporting Instructions
collapse Display Location : Reporting Templates ‎(7)
GIC_Monitor_Data_Template.xlsxGIC Monitor Data Template
GIC_Monitor_Device_Template.xlsxGIC Monitor Device Template
GMD_CI_Request_form.pdfGMD Confidential Information Designation Request Form
Magnetometer_Data_Template.xlsxMagnetometer Data Template
Magnetometer_Device_Template.xlsxMagnetometer Device Template
Missing_Data_Data_Quality_Report_Template.xlsxMissing Data - Data Quality Report Template
Process_for_Requesting_Confidential_Treatment_of_GMD_data.pdfProcess for Requesting Confidential Treatment of GMD Data