Skip to Main content Skip to Navigation
Journal articles

Solar forcing of the semi-annual variation of length-of-day

Abstract : We study the evolution of the amplitude A of the semi-annual variation of the length-of-day (lod) from 1962 to 2009. We show that A is strongly modulated (up to 30%) by the 11-yr cycle monitored by the sunspot number WN. A and WN are anticorrelated, WN leading A by 1-yr. A is therefore directly correlated with galactic cosmic ray intensity. The main part of the semi-annual variation in lod is due to the variation in mean zonal winds. We conclude that variations in mean zonal winds are modulated by the solar activity cycle through variations in irradiance, solar wind or cosmic ray intensity.
Document type :
Journal articles
Complete list of metadata

https://hal-insu.archives-ouvertes.fr/insu-03605302
Contributor : Nathalie POTHIER Connect in order to contact the contributor
Submitted on : Friday, March 11, 2022 - 9:48:11 AM
Last modification on : Sunday, March 13, 2022 - 3:25:52 AM

File

Geophysical Research Letters -...
Publisher files allowed on an open archive

Licence

Public Domain

Identifiers

Citation

Jean-Louis Le Mouël, Elena Blanter, Mikhail Shnirman, Vincent Courtillot. Solar forcing of the semi-annual variation of length-of-day. Geophysical Research Letters, American Geophysical Union, 2010, 37, ⟨10.1029/2010GL043185⟩. ⟨insu-03605302⟩

Share

Metrics

Record views

17

Files downloads

7