2016
Ref: SCART-2016-0001

Separating climate-induced mass transfers and instrumental effects from tectonic signal in repeated absolute gravity measurements

Van Camp, M. ; de Viron, O. ; Avouac, J.-P.

Abstract: We estimate the signature of the climate-induced mass transfers in repeated absolute gravity measurements based on satellite gravimetric measurements from the GRACE mission. We show results at the globe scale, and compare them with repeated absolute gravity (AG) time behavior in three zones where AG surveys have been published: Northwestern Europe, Canada and Tibet. For 10 yearly campaigns, the uncertainties affecting the determination of a linear gravity rate of change range 3-4 nm/s2/a in most cases, in absence of instrumental artefacts. The results are consistent with what is observed for long term repeated campaigns. We also discuss the possible artifact that can results from using short AG survey to determine the tectonic effects in a zone of high hydrological variability. We call into question the tectonic interpretation of several gravity changes reported from stations in Tibet, in particular the variation observed prior to the 2015 Gorkha earthquake.

Keyword(s): -The signature of climate-induced interannual mass transfers on repeated absolute gravity measurements is estimated everywhere in the world ; -Instrumental artefacts should be taken into account and mitigated as much as possible. ; -In most cases, the uncertainty is estimated to ~5 nm/s²/a after 10 yearly campaigns
DOI: 10.1002/2016GL068648
Links: link


The record appears in these collections:
Royal Observatory of Belgium > Seismology & Gravimetry
Science Articles > Peer Reviewed Articles



 Record created 2016-04-27, last modified 2016-05-18