Challenging ring-current models of the Carrington storm
Links
- More information: Publisher Index Page (via DOI)
- Open Access Version: Publisher Index Page
- Download citation as: RIS | Dublin Core
Abstract
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-folding timescale of 0.31 hr (19 min). Both of these timescales are much shorter than those characterizing the drift period of ring-current ions. Furthermore, over one 28-min interval when absolute disturbance was increasing, the data indicate an absolute rate of change of ≥2,436 nT/hr. If this is representative of disturbance generated by a symmetric magnetospheric ring current, then, assuming a standard and widely used parameterization, an interplanetary electric field of ≥451 mV/m is indicated. An idealized and extreme solar-wind dynamic pressure could, conceivably, reduce this bound on the interplanetary electric field to ≥202 mV/m. If the parameterization for electric-field extrapolation is accurate, but the field strengths obtained are deemed implausible, then it can be concluded that the Colaba disturbance data were significantly affected by partial-ring, field-aligned, or ionospheric currents. The same conclusion is supported by the shortness of the e-folding timescales characterizing the Colaba data. Several prominent studies of the Carrington event need to be reconsidered.
| Publication type | Article |
|---|---|
| Publication Subtype | Journal Article |
| Title | Challenging ring-current models of the Carrington storm |
| Series title | Journal of Geophysical Research Space Physics |
| DOI | 10.1029/2024JA032541 |
| Volume | 129 |
| Issue | 9 |
| Year Published | 2024 |
| Language | English |
| Publisher | American Geophysical Union |
| Contributing office(s) | Geologic Hazards Science Center - Seismology / Geomagnetism |
| Description | e2024JA032541, 24 p. |
| Google Analytic Metrics | Metrics page |