Print Email Facebook Twitter J2: An evaluation of new estimates from GPS, GRACE, and load models compared to SLR Title J2: An evaluation of new estimates from GPS, GRACE, and load models compared to SLR Author Lavallée, D.A. Moore, P. Clarke, P.J. Petrie, E.J. Van Dam, T. King, M.A. Faculty Aerospace Engineering Date 2010-11-19 Abstract Changes in J2, resulting from past and present changes in Earth's climate, are traditionally observed by Satellite Laser ranging (SLR). Assuming an elastic Earth, it is possible to infer changes in J2 from changes in Earth's shape observed by GPS. We compare estimates of non-secular J2 changes from GPS, SLR, GRACE, and a load model. The GPS and SLR annual signals agree but are different (16%) to the load model. Subtraction of the load model removes the annual variation from GPS, SLR, and GRACE, and the semi-annual variation in GPS. The GPS and SLR long-term signals are highly correlated, but GPS is better correlated with the loading model. Subtraction of the load model removes the 1998 anomaly from the GPS J2 series but not completely from the SLR J2 series, suggesting that the SLR anomaly may not be entirely due to mass re-distribution as has been presumed. Subject J2dynamic oblatenessloadingGPSSLRGRACE To reference this document use: http://resolver.tudelft.nl/uuid:ae0c0812-1d6b-4b6c-9a8d-466950519c06 DOI https://doi.org/10.1029/2010GL045229 Publisher American Geophysical Union ISSN 0094-8276 Source Geophysical Research Letters, 37, 2010 Part of collection Institutional Repository Document type journal article Rights (c) 2010 The Author(s)American Geophysical Union Files PDF Lavallee2_2010.pdf 174.72 KB Close viewer /islandora/object/uuid:ae0c0812-1d6b-4b6c-9a8d-466950519c06/datastream/OBJ/view