Recalibration of Bartels' Geomagnetic Activity Indices Kp and ap to Include Universal Time Variations,
Abstract
The ap index (and derived indices) can be recalibrated using Mayuad's am-index to recover the correct Universal Time variations. Such variations were artificially removed in the original ap-index. A number of tests are performed to show that the correct index is capable of revealing the desired variations. These tests include comparisons of the UT-variations on days of opposite interplanetary magnetic sector polarity. A finding, that geomagnetic activity was considerably higher during intervals of Toward polarity prior to 1963, is strongly confirmed.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1975
- Accession Number
- ADA021782
Entities
People
- Leif Svalgaard
Organizations
- Stanford University