Geomagnetism

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We monitor the Earth's magnetic field. Using ground-based observatories, we provide continuous records of magnetic field variations; disseminate magnetic data to various governmental, academic, and private institutions; and conduct research into the nature of geomagnetic variations for purposes of scientific understanding and hazard mitigation.

Keeping the Lights On in North America

Keeping the Lights On in North America

Realtime geoelectric maps during a magnetic storm can assist utility companies with their operations and can help power-grid managers to make decisions that may minimize the impact to their systems.

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Risk of Once-Per-Century Geomagnetic Superstorm in NE United States

Risk of Once-Per-Century Geomagnetic Superstorm in NE United States

A new report and map published by the U.S. Geological Survey provides critical insight to electric power grid operators across the northeastern United States in the event of a once-per-century magnetic superstorm.  

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Auroras and Earthquakes: Strange Companions

Auroras and Earthquakes: Strange Companions

In a win-win situation for both seismologists and space physicists, a cheap magnetometer at a seismic station can result in better seismic data for earthquakes and also more geomagnetic data in real time for monitoring space weather.

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News

Date published: July 31, 2020

Auroras and Earthquakes: Strange Companions

In a win-win situation for both seismologists and space physicists, a cheap magnetometer at a seismic station can result in better seismic data for earthquakes and also more geomagnetic data in real time for monitoring space weather.

Read the new Science for Everyone article: Auroras...

Date published: May 12, 2020

Announcing Gavin Hayes as USGS Senior Science Advisor for Earthquake & Geologic Hazards

On May 10, Gavin Hayes takes on the role of Senior Science Advisor for Earthquake and Geologic Hazards within the USGS Natural Hazards Mission Area.  The Senior Science Advisor serves as the coordinator for the Earthquake Hazards, Global Seismographic Network, and Geomagnetism Programs and provides oversight and guidance across the full breadth of USGS geohazard-related activities.

Date published: March 16, 2020

New Geoelectric Hazard Map Shows Potential Vulnerability to High-Voltage Power Grid for Two-Thirds of the US

The U.S. Geological Survey released a new report on geoelectric hazards for two-thirds of the contiguous U.S., spanning from the northeast to the west coast of the Nation. 

Publications

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Year Published: 2019

Intensity and impact of the New York Railroad superstorm of May 1921

Analysis is made of low‐latitude ground‐based magnetometer data recording the magnetic superstorm of May 1921. By inference, the storm was driven by a series of interplanetary coronal mass ejections, one of which produced a maximum pressure on the magnetopause of ~64.5 nPa, sufficient to compress the subsolar magnetopause radius to ~5.3 Earth...

Love, Jeffrey J.; Hayakawa, Hisashi; Cliver, Edward W.

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Year Published: 2019

Data sharing in magnetotellurics

Here, we introduce the first openly available comprehensive database of magnetotelluric (MT) and related electromagnetic data that we developed and matured over the past decade, explain how to access the data, and describe the challenges that had to be overcome to make MT data sharing possible. The database is a helpful tool for MT scientists, and...

Kelbert, Anna; Erofeeva, Svetlana; Trabant, Chad; Karstens, Rich; Van Fossen, Mickey C.

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Year Published: 2019

The extreme space weather event in September 1909

We evaluate worldwide low-latitude auroral activity associated with the great magnetic storm of September 1909 for which a minimum Dst value of −595 nT has recently been determined. From auroral observations, we calculate that the equatorward boundary of the auroral oval in the 1909 event was in the range from 31°–35° invariant latitude (...

Hayakawa, Hisashi; Ebihara, Yusuke; Cliver, Edward W.; Hattori, Kentaro; Toriumi, Shin; Love, Jeffrey J.; Umemura, Norio; Namekata, Kosuke; Sakaue, Takahito; Takahashi, Takuya; Shibata, Kazunari