[en] 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.
Disciplines :
Physics Earth sciences & physical geography
Identifiers :
UNILU:UL-ARTICLE-2011-031
Author, co-author :
Lavalee, D.; School of Civil Engineering and Geosciences, Newcastle University, UK
Moore, P.; School of Civil Engineering and Geosciences, Newcastle University, UK
Clarke, Peter J.; School of Civil Engineering and Geosciences, Newcastle University, UK
Petrie, E.; School of Civil Engineering and Geosciences, Newcastle University, UK
van Dam, Tonie ; University of Luxembourg > Faculty of Science, Technology and Communication (FSTC) > Engineering Research Unit
King, M.; School of Civil Engineering and Geosciences, Newcastle University, UK
Language :
English
Title :
An Evaluation of New Estimates from GPS, GRACE and Load Models compared to SLR
Publication date :
2010
Journal title :
Geophysical Research Letters
ISSN :
0094-8276
eISSN :
0094-8276
Publisher :
American Geophysical Union, Washington, United States - District of Columbia
