Abstract
An important subject in the climate debate is the study of the major ice sheets mass balance. Knowledge of the mass balance provides understanding of changes in the relative sea-level (RSL). Several methods are used for mass balance studies but they are associated with large uncertainties. One reason for the uncertainty is the presence of the postglacial rebound (PGR) signal in the geodetic data used for mass balance estimates. Estimates of the PGR signal can be obtained by modelling and then being subtracted from the data to eliminate its influence. In this study, the PGR gravity signal will be investigated through modelling. The modelling of seven different scenarios shows that the PGR gravity signal in Greenland is less then 1 μGal/year (1 μGal = 10 nm/s2). Repeated absolute gravity (AG) measurements at selected Greenland network (GNET) GPS sites were initiated in 2009. These data will in the future help constrain PGR and present-day ice mass changes. The data is collected with an A10 absolute gravimeter, which has an accuracy of 10 μGal (manufacturer specification). Here we will evaluate the modelled PGR gravity signal at selected GNET sites and conclude that the signal is significantly smaller then the gravity instruments accuracy and a long time is needed to detect it. Also, it can be expected that the elastic signal will be larger and other data like GPS is needed to separate the viscous and elastic signal.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
References
Argus DF, Peltier WR (2010) Constraining models of postglacial rebound using space geodesy: a detailed assessment of model ICE-5G (VM2) and its relatives. Geophys J Int 181:697–723
Barletta VR, Sabadini R, Bordoni A (2008) Isolating the PGR signal in the GRACE data: impact on mass balance estimates in Antarctica and Greenland. Geophys J Int 172:18–30
Bevis M, Kendrick E, Smalley R Jr, Dalziel I, Caccamise D, Sasgen I, Helsen M, Taylor FW, Zhou H, Brown A, Raleigh D, Willis M, Wilson T, Konfal S (2009) Geodetic measurements of vertical crustal velocity in West Antarctica and the implications for ice mass balance. Geochem Geophys Geosyst 10:1–11
Derbyshire FA, Larsen TB, Mosegaard K, Dahl-Jensen T, Gudmundsson O, Bach T, Gregersen S, Pedersen HA, Hanka W (2004) A first look at the Greenland lithosphere and upper mantle using Rayleigh wave tomography. Geophys J Int 158:267–286
Dziewonski AM, Anderson DL (1981) Preliminary reference Earth model. Phys Earth Planet Inter 25:297–356
Falk R, Müller J, Lux H, Wilmes H, Wziontek H (2009) Precise gravimetric surveys with the field absolute gravimeter A10. Geodesy for planet Earth: proceedings of the 2009 IAG symposium, Buenos Aires, Argentina, 31 August to 9 September. Springer, Berlin, pp 273–279
Farrell WE, Clark JA (1976) On postglacial sea level. Geophys J R Astron Soc 46:647–667
Greve R (1997) Application of a polythermal three-dimensional ice sheet model to the Greenland ice sheet—response to steady-state and transient climate scenarios. J Climate 10:901–918
Khan SA, Liu L, Wahr J, Howat I, Joughin I, van Dam T, Fleming K (2010) GPS measurements of crustal uplift near Jakobshavn Isbræ due to glacial ice mass loss. J Geophys Res 115:1–13
Lidberg M, Johansson JM, Scherneck HG, Milne GA (2010) Recent results based on continuous GPS observations of the GIA process in Fennoscandia from BIFROST. J Geodyn 50:8–18
Mazzotti S, Lambert A, Henton J, James TS, Courtier N (2011) Absolute gravity calibration of GPS velocities and glacial isostatic in mid-continent North America. Geophys Res Lett 38:1–5
Mémin A, Rogister Y, Hinderer J, Omang OC, Luck B (2011) Secular gravity variation at Svalbard (Norway) from ground observations and GRACE satellite data. Geophys J Int 184:1119–1130
Mémin A, Hinderer J, Rogister Y (2011) Separation of the geodetic consequences of past and present ice-mass change: influence of topography with application to Svalbard (Norway). Pure Appl Geophys. doi:10.1007/s00024-011-0399-7
Mitrovica JX, Peltier WR (1989) Pleistocene deglaciation and the global gravity field. J Geophys Res 94:651–671
Mitrovica J, Peltier W (1991) On postglacial geoid subsidence over the equatorial oceans. J Geophys Res 96:53–71
Okubo S, Yoshida S, Sato T, Tamura Y, Imanishi Y (1997) Verifying the precision of a new generation absolute gravimeter FG5—comparison with superconducting gravimeters and detection of oceanic loading tide. Geophys Res Lett 24:489–492
Okuno J, Nakada M (2001) Effects of water load on geophysical signals due to glacial rebound and implications for mantle viscosity. Earth Planets Space 53:1121–1135
Peltier WR (1998) Postglacial variations in the level of the sea: implications for climate dynamics and solid earth geodynamics. Rev Geophys 36:603–689
Peltier WR (2004) Global glacial isostasy and the surface of the ice-age Earth: the ICE-5G (VM2) model and GRACE. Annu Rev Earth Planet Sci 32:111–149
Peltier WR, Tushingham AM (1993) Relative Sea Level Database. IGBP PAGES/World Data Center for Paleoclimatology Data Contribution. NOAA/NCDC Paleoclimatology Program, pp 93–016
Sella GF, Stein S, Dixon TH, Craymer M, James TS, Mazzotti S, Dokka RK (2007) Observation of glacial isostatic adjustment in stable North America with GPS. Geophys Res Lett 34:1–6. doi:10.1029/2006GL027081
Spada G, Stocchi P (2007) SELEN—A Fortran 90 program for solving the sea-level-equation. Comput Geosci 33:538–562
Spada G, Barletta VR, Klemann V, Riva REM, Martinec Z, Gasperini P, Lund B, Wolf D, Vermeersen LLA, King MA (2011) A benchmark study for glacial isostatic adjustment codes. Geophys J Int 185:106–132
Steffen H, Gitlein O, Denker H, Müller J, Timmen L (2009) Present rate of uplift in Fennoscandia from GRACE and absolute gravimetry. Tectonophysics 474:69–77
Sun W, Miura S, Sato T, Sugano T, Freymueller J, Kaufman M, Larsen CF, Cross R, Inazu D (2010) Gravity measurements in southeastern Alaska reveal negative gravity rate of change caused by Glacial Isostatic Adjustment. J Geophys Res 115:1–40
Tushingham AM, Peltier WR (1991) Ice-3G—a new global model of late Pleistocene deglaciation based upon geophysical predictions of post-glacial relative sea level change. J Geophys Res 96:4497–4523
Van Dam T, Larson K, Wahr J, Francis O (2000) Using GPS and gravity to infer ice mass changes in Greenland. EOS Trans Am Geophys Union 81:421–427
Wahr J, Dazhong H (1997) Prediction of crustal deformations caused by changing polar ice on a viscoelastic Earth. Surv Geophys 18: 303–312
Wahr J, van Dam T, Larson K, Francis O (2001) Geodetic measurements in Greenland and their implications. J Geophys Res 106:567–581
Whitehouse P (2009) Glacial isostatic adjustment and sea-level change—state of the art report. Durham University/Svensk Kärnbränslehantering AB
Wu P, Peltier WR (1983) Glacial isostatic adjustment and the free air gravity anomaly as a constraint on the deep mantle viscosity. Geophys J R Astron Soc 74:377–449
Acknowledgements
Thanks go to Gudfinna Adalgeirsdottier (Danish Metrological Institute) for generating the SICOPOLIS ice model for Greenland and Giorgio Spada (Urbino University “Carlo Bo”) for assistance in working with his program.
Author information
Authors and Affiliations
Corresponding author
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2014 Springer-Verlag Berlin Heidelberg
About this paper
Cite this paper
Nielsen, E., Strykowski, G., Forsberg, R., Madsen, F.B. (2014). Estimation of PGR Induced Absolute Gravity Changes at Greenland GNET Stations. In: Rizos, C., Willis, P. (eds) Earth on the Edge: Science for a Sustainable Planet. International Association of Geodesy Symposia, vol 139. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-642-37222-3_12
Download citation
DOI: https://doi.org/10.1007/978-3-642-37222-3_12
Published:
Publisher Name: Springer, Berlin, Heidelberg
Print ISBN: 978-3-642-37221-6
Online ISBN: 978-3-642-37222-3
eBook Packages: Earth and Environmental ScienceEarth and Environmental Science (R0)