Reconstructing the long-term aa index

• Published in: Journal of Geophysical Research
• Main Authors: Clilverd, Mark A., Clarke, Ellen, Ulich, Thomas, Linthe, Joachim, Rishbeth, Henry
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: American Geophysical Union 2005
• Subjects: Space Sciences; Sodankylä
• Online Access: http://nora.nerc.ac.uk/id/eprint/1703/; http://www.agu.org/pubs/crossref/2005/2004JA010762.shtml; https://doi.org/10.1029/2004JA010762

The robustness of the aa geomagnetic index is of critical importance to the debate about the previously reported doubling of the solar coronal magnetic field in the last 100 years, inferred from an increasing trend in this index. To test the trend in aa, we have reconstructed the aa index using two...