Geomagnetism Program | U.S. Geological Survey (original) (raw)

News

July 15, 2023

Publications

October 16, 2024

The solar cycle, geology, and geoelectric hazards for power grids

When sunspots are large and numerous, intense magnetic storms are likely to occur on the Earth. Magnetic storms can generate electric fields in the Earth, and these fields can, in turn, interfere with electric power transmission grids that are grounded at the Earth’s surface. Across the contiguous United States, geoelectric hazards are highest in the Upper Midwest and in the East. These regions co

September 3, 2024

Challenging ring-current models of the Carrington storm

A detailed analysis is made of horizontal-component geomagnetic-disturbance data acquired at the Colaba observatory in India recording the Carrington magnetic storm of September 1859. Prior to attaining its maximum absolute value, disturbance at Colaba increased with an e-folding timescale of 0.46 hr (28 min). Following its maximum, absolute disturbance at Colaba decreased as a trend having an e-f

Authors

Jeffrey J. Love, Kalevi Mursula

August 21, 2024

On the uncertain intensity estimate of the 1859 Carrington storm

A study is made of the intensity of the Carrington magnetic storm of September 1859 as inferred from visual measurements of horizontal-component geomagnetic disturbance made at the Colaba observatory in India. Using data from modern observatories, a lognormal statistical model of storm intensity is developed, to characterize the maximum-negative value of the storm-time disturbance index (maximum –

Authors

Jeffrey J. Love, E. Joshua Rigler, H. Hayakawa, Kalevi Mursula