@article{fa5c6dc576c04626ab7587d6d5ac8656,
title = "GPS Rates of Vertical Bedrock Motion Suggest Late Holocene Ice-Sheet Readvance in a Critical Sector of East Antarctica",
abstract = "We investigate present-day bedrock vertical motion using new Global Positioning System (GPS) timeseries from the Totten-Denman glacier region of East Antarctica (∼77°–120°E) where models of glacial isostatic adjustment (GIA) disagree, glaciers are likely losing mass, and few data constraints on GIA exist. We show that varying surface mass balance loading (SMBL) is a dominant signal, contributing random-walk-like noise to GPS timeseries across Antarctica. In the study region, it induces site velocity biases of up to ∼+1 mm/yr over 2010–2020. After correcting for SMBL displacement and GPS common mode error, subsidence is evident at all sites aside from the Totten Glacier region where uplift is ∼1.5 mm/yr. Uplift near the Totten Glacier is consistent with late Holocene ice retreat while the widespread subsidence further west suggests possible late Holocene readvance of the region{\textquoteright}s ice sheet, in broad agreement with limited glacial geological data and highlighting the need for sampling beneath the current ice sheet.",
keywords = "Antarctica, common mode error, glacial isostatic adjustment, GPS, late Holocene, surface mass balance",
author = "King, {Matt A.} and Watson, {Christopher S.} and Duanne White",
note = "Funding Information: The authors thank the Editor and anonymous reviewers for their helpful remarks. This work was supported by the Australian Research Council (ARC) Special Research Initiative for Antarctic Gateway Partnership (Project ID SR140300001), ARC Australian Centre for Excellence in Antarctic Science (Project ID SR200100008), and from the Australian Government{\textquoteright}s Australian Antarctic Program (Project 4318). The latter grant supported the deployment and maintenance of the CAD sites within the CaDaGIA network and the maintenance of BHIL. CAS1, DAV1, and MAW1 are part of the International GNSS Service network and are operated by Geoscience Australia. This paper is a contribution to the Scientific Committee for Antarctic Research (SCAR) GIANT REGAIN project. The authors acknowledge the efforts of many people to deploy and maintain the GPS sites, with fieldwork led by Sue Cook, Tobias Staal and Ben Galton‐Fenzi. The authors thank Michiel van den Broeke and Chris Kittel for making SMB model outputs available, Andrew Shepherd and Lin Gilbert for making the altimetry data available, and Leonid Petrov for providing ATML data. Roelof Rietbroek proposed the algorithm for estimating offsets with local data only. The authors thank Valentina Barletta and Andrea Bordoni for providing the E‐CL0V3RS software. The authors thank NASA JPL for making GIPSY and associated satellite orbit and clock products available. Open access publishing facilitated by University of Tasmania, as part of the Wiley ‐ University of Tasmania agreement via the Council of Australian University Librarians. Funding Information: The authors thank the Editor and anonymous reviewers for their helpful remarks. This work was supported by the Australian Research Council (ARC) Special Research Initiative for Antarctic Gateway Partnership (Project ID SR140300001), ARC Australian Centre for Excellence in Antarctic Science (Project ID SR200100008), and from the Australian Government?s Australian Antarctic Program (Project 4318). The latter grant supported the deployment and maintenance of the CAD sites within the CaDaGIA network and the maintenance of BHIL. CAS1, DAV1, and MAW1 are part of the International GNSS Service network and are?operated by Geoscience Australia. This paper is a contribution to the Scientific Committee for Antarctic Research (SCAR) GIANT REGAIN project. The authors acknowledge the efforts of many people to deploy and maintain the GPS sites, with fieldwork led by Sue Cook, Tobias Staal and Ben Galton-Fenzi. The authors thank Michiel van den Broeke and Chris Kittel for making SMB model outputs available, Andrew Shepherd and Lin Gilbert for making the altimetry data available, and Leonid Petrov for providing ATML data. Roelof Rietbroek proposed the algorithm for estimating offsets with local data only. The authors thank Valentina Barletta and Andrea Bordoni for providing the E-CL0V3RS software. The authors thank NASA JPL for making GIPSY and associated satellite orbit and clock products available. Open access publishing facilitated by University of Tasmania, as part of the Wiley - University of Tasmania agreement via the Council of Australian University Librarians. Publisher Copyright: {\textcopyright} 2022. The Authors.",
year = "2022",
month = feb,
day = "28",
doi = "10.1029/2021GL097232",
language = "English",
volume = "49",
pages = "1--10",
journal = "Geophysical Research Letters",
issn = "0094-8276",
publisher = "Wiley-Blackwell",
number = "4",
}