Mass changes across the Antarctic ice sheet have been detected using satellite gravimetry, revealing significant instabilities in major glacier basins of East Antarctica as well as across the entire ice sheet. [emphasis, links added]
The Antarctic Ice Sheet (AIS) plays a major role in global sea-level rise. Since March 2002, the GRACE (Gravity Recovery and Climate Experiment) mission and its successor, GRACE-FO (GRACE Follow-On), have provided valuable data to monitor changes in ice mass across the AIS.
Previous studies have consistently shown a long-term trend of mass loss, particularly in West Antarctica and the Antarctic Peninsula, while glaciers in East Antarctica appeared relatively stable.
However, a recent study led by Dr. Wang and Prof. Shen at Tongji University has found a surprising shift: between 2021 and 2023, the AIS experienced a record-breaking increase in overall mass.
Notably, four major glaciers in the Wilkes Land–Queen Mary Land region of East Antarctica reversed their previous pattern of accelerated mass loss from 2011 to 2020 and instead showed significant mass gain during the 2021 to 2023 period.
Record-breaking mass gain over the Antarctic Ice Sheet
From 2002 to 2010, the AIS has experienced a mass loss with a change rate of –73.79±56.27 Gt/yr, which nearly doubled to –142.06±56.12 Gt/yr for the period 2011–2020.
This accelerated mass loss was primarily related to intensified mass depletion in West Antarctica and the WL-QML region of East Antarctica.
However, a significant reversal occurred thereafter, driven by anomalous precipitation accumulation, the AIS gained mass at a rate of 107.79±74.90 Gt/yr between 2021 and 2023.
Correspondingly, the contribution of mass change over the AIS to global mean sea level rise was 0.20±0.16 mm/yr during 2002–2010 and 0.39±0.15 mm/yr during 2011–2020.
In contrast, during 2021–2023, it exerted a negative contribution, offsetting global mean sea level rise at a rate of 0.30±0.21 mm/yr.
Enhanced mass loss of the Totten, Moscow, Denman, and Vincennes Bay glacier basins, East Antarctica
The four key glacier basins in WL-QML region, i.e., Totten, Moscow University, Denman, and Vincennes Bay, exhibited mass loss intensification with a rate of 47.64±8.14 Gt/yr during 2011-2020, compared to 2002-2010, with the loss area expanding inland.
The researchers explained, “This accelerated mass loss was primarily driven by two factors: surface mass reduction (contributing 72.53%) and increased ice discharge (27.47%).”
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