Accession Number:

ADA021782

Title:

Recalibration of Bartels' Geomagnetic Activity Indices Kp and ap to Include Universal Time Variations,

Descriptive Note:

Corporate Author:

STANFORD UNIV CALIF INST FOR PLASMA RESEARCH

Personal Author(s):

• Svalgaard,Leif

Report Date:

1975-12-01

Pagination or Media Count:

28.0

Abstract:

The ap index and derived indices can be recalibrated using Mayuads 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.

Descriptors:

• *GEOMAGNETISM
• CALIBRATION
• MAGNETOSPHERE
• PERIODIC VARIATIONS

Subject Categories:

• Atmospheric Physics
• Geomagnetism

Distribution Statement:

APPROVED FOR PUBLIC RELEASE