Re-establishment of ice-surface velocity field and snow surface elevation change around Dome Argus, East Antarctica

Hao Ke,Dongchen E,Yuande Yang,Minghu Ding,Bo Sun,Zemin Wang,Bo Jin,Fei Li

doi:10.1017/aog.2019.3

Abstract

ABSTRACTIn January 2016, static GPS measurements were carried out in a 30 × 30 km2 area centered around Kunlun station at Dome Argus (Dome A), East Antarctica, to acquire high-precision 3-D geodetic coordinates at 49 sites. By comparing the coordinates with previous GPS measurements in 2008 and 2013 at the same sites, we constructed a detailed and long-term record of the ice-surface velocity field, 2008–2016, around Dome A. During this time span, the estimated ice-surface velocity ranges from 0.8 ± 0.3 to 28.7 ± 1.6 cm a−1, with a mean of 10.4 ± 0.3 cm a−1. From 2013 to 2016, the surface elevation of most Dome A areas exhibits a rising trend, and the maximum increase of snow surface elevation is 84.8 cm. The mean snow surface elevation change rate at Dome A is estimated to be 6.6 ± 0.7 cm a−1. The difference of 1.0 cm a−1 between the snow surface change rate derived from GPS and pole-height change rate from surface mass balance is suspected to be a result of a combination of firn densification and basal melt under Dome A.

Highlights

As the highest region of the East Antarctic ice sheet, Dome Argus (Dome A) is one of the most important candidate sites from which to acquire the oldest East Antarctic ice core (Ding and others, 2016)
Information about surface topography, ice thickness, ice velocity, snow accumulation, and strain field is critical to the interpretation of ice core records (Wesche and others, 2007; Xiao and others, 2008; Yang and others, 2014)
Various scientific studies have been carried out at Dome A, since its summit was reached during the 21st Chinese National Antarctic Scientific Expedition (CHINARE) in 2005

Summary

Introduction

As the highest region of the East Antarctic ice sheet, Dome Argus (Dome A) is one of the most important candidate sites from which to acquire the oldest East Antarctic ice core (Ding and others, 2016). Yang and others (2014) calculated the velocity and strain fields around Dome A using repeat GPS measurements at 12 poles occupied in 2008 and 2013.

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Results

Conclusion