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Abstract. Grounding line discharge is a key component of the mass balance of the Antarctic Ice Sheet. Here we present an estimate of Antarctic Ice Sheet grounding line discharge from 1996 through to last month. We calculate ice flux at up to 100 m resolution through 16 algorithmically-generated flux gates, which are continuous around Antarctica. We draw on a range of ice velocity and thickness data to estimate grounding line discharge. For ice thickness, we use four bed topography datasets, two firn models and a temporally varying ice surface. For the ice velocity, we utilise a range of publicly-available ice velocity maps at resolutions ranging from 240 x 240 m to 1000 x 1000 m, as well as new, 100 x 100 m monthly velocity mosaics derived from intensity-tracking of Sentinel-1 image pairs, available since October 2014. The pixel-based ice fluxes and ice flux errors are integrated within all available Antarctic ice stream, ice shelf and glacier basins. Our dataset also includes the contributions to discharge from changes in ice thickness due to surface lowering, time-varying firn air content and surface mass change between the flux gates and grounding line. We find that Antarctic Ice Sheet grounding line discharge increased from 1,990 ± 23 Gt yr-1 to 2,205 ± 18 Gt yr-1 between 1996 and 2023, much of which was due to acceleration of ice streams in West Antarctica but with substantial contributions from ice streams in East Antarctica and glaciers on the Antarctic Peninsula. The uncertainties in our discharge dataset primarily result from uncertain bed elevation and flux gate location, which account for much of difference between our results and previous studies. It is our intention to update this discharge dataset each month, subject to continued Sentinel-1 acquisitions and funding availability. [ABSTRACT FROM AUTHOR]

Due to rapid global warming, the relationship between the mass loss of the Antarctic ice sheet and rising sea levels are attracting widespread attention. The Lambert–Amery glacial system is the largest drainage system in East Antarctica, and its mass balance has an important influence on the stability of the Antarctic ice sheet. In this paper, the recent ice flux in the Lambert Glacier of the Lambert–Amery system was systematically analyzed based on recently updated remote sensing data. According to Landsat-8 ice velocity data from 2018 to April 2019 and the updated Bedmachine v2 ice thickness dataset in 2021, the contribution of ice flux approximately 140 km downstream from Dome A in the Lambert Glacier area to downstream from the glacier is 8.5 ± 1.9   Gt · a − 1 , and the ice flux in the middle of the convergence region is 18.9 ± 2.9   Gt · a − 1 . The ice mass input into the Amery ice shelf through the grounding line of the whole glacier is 19.9 ± 1.3   Gt · a − 1 . The ice flux output from the mainstream area of the grounding line is 19.3 ± 1.0   Gt · a − 1 . Using the annual SMB data of the regional atmospheric climate model (RACMO v2.3) as the quality input, the mass balance of the upper, middle, and lower reaches of the Lambert Glacier was analyzed. The results show that recent positive accumulation appears in the middle region of the glacier (about 74–78°S, 67–85°E) and the net accumulation of the whole glacier is 2.4 ± 3.5   Gt · a − 1 . Although the mass balance of the Lambert Glacier continues to show a positive accumulation, and the positive value in the region is decreasing compared with values obtained in early 2000. [ABSTRACT FROM AUTHOR]