Accessibility navigation


Near-Earth heliospheric magnetic field intensity since 1750. Part 2: cosmogenic radionuclide reconstructions

Owens, M. J., Cliver, E., McCracken, K. G., Beer, J., Barnard, L., Lockwood, M., Rouillard, A., Passos, D., Riley, P., Usoskin, I. and Wang, Y.-M. (2016) Near-Earth heliospheric magnetic field intensity since 1750. Part 2: cosmogenic radionuclide reconstructions. Journal of Geophysical Research: Space Physics, 121 (7). pp. 6064-6074. ISSN 2169-9402

[img]
Preview
Text (Open Access) - Published Version
· Available under License Creative Commons Attribution.
· Please see our End User Agreement before downloading.

1MB
[img] Text (Permanent Publisher Embargo) - Accepted Version
· Restricted to Repository staff only

1MB

It is advisable to refer to the publisher's version if you intend to cite from this work. See Guidance on citing.

To link to this item DOI: 10.1002/2016JA022550

Abstract/Summary

This is Part 2 of a study of the near-Earth heliospheric magnetic field strength, B, since 1750. Part 1 produced composite estimates of B from geomagnetic and sunspot data over the period 1750–2013. Sunspot-based reconstructions can be extended back to 1610, but the paleocosmic ray (PCR) record is the only data set capable of providing a record of solar activity on millennial timescales. The process for converting 10Be concentrations measured in ice cores to B is more complex than with geomagnetic and sunspot data, and the uncertainties in B derived from cosmogenic nuclides (~20% for any individual year) are much larger. Within this level of uncertainty, we find reasonable overall agreement between PCR-based B and the geomagnetic- and sunspot number-based series. This agreement was enhanced by excising low values in PCR-based B attributed to high-energy solar proton events. Other discordant intervals, with as yet unspecified causes remain included in our analysis. Comparison of 3 year averages centered on sunspot minimum yields reasonable agreement between the three estimates, providing a means to investigate the long-term changes in the heliospheric magnetic field into the past even without a means to remove solar proton events from the records.

Item Type:Article
Refereed:Yes
Divisions:Faculty of Science > School of Mathematical, Physical and Computational Sciences > Department of Meteorology
ID Code:65894
Publisher:American Geophysical Union

Downloads

Downloads per month over past year

University Staff: Request a correction | Centaur Editors: Update this record

Page navigation