EGUsphere EGUsphere EGUsphere EGUsphere Copernicus Publications Göttingen, Germany 10.5194/egusphere-2026-2150 Accurate assessment of surface mass balance based on stake observations and model correction at Dome A, East Antarctica Zhang Xiyue https://orcid.org/0009-0003-8107-2195 1 Ding Minghu https://orcid.org/0000-0002-1142-6598 1 2 Yang Diyi https://orcid.org/0000-0002-1844-5900 1 3 Cheng Bin https://orcid.org/0000-0001-8156-8412 4 Allison Ian https://orcid.org/0000-0001-9599-0251 5 Zhu Kongju 1 Yang Yuande 6 7 Cui Xiangbin https://orcid.org/0000-0002-4269-8086 8 Heil Petra 9 Li Chuanjin 8 Xiao Cunde 10 State Key Laboratory of Disaster Weather Science and Technology, Chinese Academy of Meteorological Sciences, Beijing 100081, China Key Laboratory of Polar Atmosphere-Ocean-Ice System for Weather and Climate, Ministry of Education, Shanghai 200438, China Haining Meteorological Bureau, Haining 314400, China Finnish Meteorological Institute, Helsinki, Finland Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, Australia Chinese Antarctic Center of Surveying and Mapping, Wuhan University, Wuhan 430079, China Key Laboratory of Polar Environment Monitoring and Public Governance, Ministry of Education, Wuhan University, Wuhan 430079, China Antarctic Zhongshan Ice and Space Environment National Observation and Research Station, Polar Research Institute of China, Shanghai 201209, China Australian Antarctic Division and Australian Antarctic Program Partnership, University of Tasmania, Hobart, Australia State Key Laboratory of Earth Surface Processes and Resource Ecology, Beijing Normal University, Beijing 100875, China 27 05 2026 2026 1 21 Copyright: © 2026 Xiyue Zhang et al. 2026 This work is licensed under the Creative Commons Attribution 4.0 International License. To view a copy of this licence, visit https://creativecommons.org/licenses/by/4.0/ This article is available from https://egusphere.copernicus.org/preprints/2026/egusphere-2026-2150/ The full text article is available as a PDF file from https://egusphere.copernicus.org/preprints/2026/egusphere-2026-2150/egusphere-2026-2150.pdf

Accurate quantification of surface mass balance (SMB) in the Antarctic interior underpins ice sheet mass budget assessments and ice core interpretation. Stake measurements, however, systematically underestimate SMB because firn densification causes surface lowering unrelated to mass change. Here, we simulate firn compaction with a firn densification model and correct stake records from 2008-2024 at Dome Argus (Dome A), East Antarctica, thereby refining SMB estimates and their spatial variability. The mean annual corrected SMB is 24.14 kg m<sup>-2</sup> yr<sup>-1</sup>, 8.8 % higher than the uncorrected value (22.19 kg m<sup>-2</sup> yr<sup>-1</sup>). Over the stake array, the RACMO2.4p1 regional model yields lower and more spatially uniform SMB (17.50 kg m<sup>-2</sup> yr<sup>-1</sup>). Using automatic weather station observations, we estimate annual sublimation of 2.34 mm w.e yr<sup>-1</sup>. and hoar deposition of 0.87 mm w.e. yr<sup>-1</sup>, indicating that the net vapor flux is equivalent to 5.7 % of the total mass input. This framework reduces densification induced bias in stake-derived SMB, provides an observational benchmark for evaluating regional climate models, and supports accurate dating of ice core climate records from Dome A.

 National Natural Science Foundation of China 42525607 Chinese Academy of Meteorological Sciences 2023Z015 2023Z004 2023Z025