Analysis of continuous GPS measurements from southern Victoria Land, Antarctica

Michael J. Willis

doi:10.3133/ofr20071047srp065

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Analysis of continuous GPS measurements from southern Victoria Land, Antarctica

Michael J. Willis

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Abstract

Several years of continuous data have been collected at remote bedrock Global Positioning System (GPS) sites in southern Victoria Land, Antarctica. Annual to sub-annual variations are observed in the position time-series. An atmospheric pressure loading (APL) effect is calculated from pressure field anomalies supplied by the European Centre for Medium-Range Weather Forecasts (ECMWF) model loading an elastic Earth model. The predicted APL signal has a moderate correlation with the vertical position time-series at McMurdo, Ross Island (International Global Navigation Satellite System Service (IGS) station MCM4), produced using a global solution. In contrast, a local solution in which MCM4 is the fiducial site generates a vertical time series for a remote site in Victoria Land (Cape Roberts, ROB4) which exhibits a low, inverse correlation with the predicted atmospheric pressure loading signal. If, in the future, known and well modeled geophysical loads can be separated from the time-series, then local hydrological loading, of interest for glaciological and climate applications, can potentially be extracted from the GPS time-series.

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Source-reported bounding extent: -79.11° to -70.28° latitude; 149.96° to 170.34° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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BibTeX RIS

Michael J. Willis. 2007. Analysis of continuous GPS measurements from southern Victoria Land, Antarctica. https://doi.org/10.3133/ofr20071047srp065

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