ENSO Signature detected in the Earth's Geocenter
Abstract
Global mass redistribution alters Earth rotation, produces temporal variations of the gravitational field, and shifts the position of geocenter, which is defined as the center of figure (CF) of the Earth relative to the center of mass (CM) of the Earth including mass load. Variation of the geocenter reflects the global mass balance and the interactions between the solid Earth and the mobile masses on the Earth. Among all the Earth reference system parameters, the Geocenter motion is the lesser known and analyzed quantity. It can be determined by several techniques; presently Satellite Laser Ranging (SLR) gives the best results. Two geocenter series derived from SLR are utilized: 1) the analysis of Luceri et al., 2016, and 2) Pavlis et al., 2016. The agreement between the two geocenter series is very good; here, we use the Luceri et al., 2016 solution. Motion of the geocenter mirrors the global degree 1 mass distribution in the climate system and inside the solid Earth. The seasonal cycle dominates the time series, which we remove by subtracting a composite seasonal cycle. This allows us to study interannual and longer variabilities. We then investigate the climate signature in the geocenter motion, with a particular focus on the interannual timescale.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2016
- Bibcode:
- 2016AGUFM.G13B1095D
- Keywords:
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- 1217 Time variable gravity;
- GEODESY AND GRAVITYDE: 1218 Mass balance;
- GEODESY AND GRAVITYDE: 1223 Ocean/Earth/atmosphere/hydrosphere/cryosphere interactions;
- GEODESY AND GRAVITYDE: 1225 Global change from geodesy;
- GEODESY AND GRAVITY