In a groundbreaking study that redefines our understanding of the Antarctic Ice Sheet’s behavior in recent decades, researchers have documented a significant and sustained decline in surface mass balance (SMB) over the inland East Antarctic region. This revelation challenges previous satellite-based assumptions of stability or slight increases in mass accumulation, carrying profound implications for models of climate interaction and ice sheet dynamics. By leveraging data from mass balance stakes along a critical transect from Zhongshan Station to Dome A, this extensive observational effort spanning 2005 through 2020 unveils new insights into the physical mechanisms driving Antarctic mass change in this remote but climatically pivotal region.
The surface mass balance of ice sheets, defined as the net gain or loss of water equivalent through precipitation, evaporation, sublimation, and melting at the ice surface, constitutes a fundamental component of the overall ice sheet mass budget. Accurate SMB measurements are indispensable for constraining ice sheet models and evaluating their response to ongoing climatic shifts. Yet, due to the logistical challenges inherent to Antarctic field work and the spatial heterogeneity of snowfall and surface processes, SMB observations have traditionally been sparse and limited in temporal duration. Furthermore, proxy records from snow pits and ice cores, while valuable, sometimes reflect local anomalies rather than regional trends, complicating efforts to assess large-scale patterns.
This newly published investigation, led by Wang, Ma, and Li et al. and featured in Nature Geoscience (2025), overcomes many of these challenges by deploying a network of mass balance stakes along an inland transect covering approximately 1,200 kilometers stretching from the Chinese research outpost Zhongshan Station near the Antarctic coast to Dome A—the continent’s highest ice divide approximately 4,093 meters above sea level. Over 15 years of consistent monitoring, these stakes provide a uniquely robust time series of SMB data, enabling the detection of subtle but significant temporal trends previously unattainable via remote sensing or short-term campaigns.
What emerged from this meticulous work was a clear, statistically significant downward trend in the surface mass balance across the inland transect, registering a mean decline of approximately −2.01 ± 0.37 kilograms per square meter per year squared over the 2005–2020 timeframe. This equates to a roughly 35.5% diminution in SMB, a stark contrast to the prevailing narrative of either steady or slightly increasing surface accumulation in East Antarctica. Notably, the decline is spatially coherent and consistent over the entirety of the studied region, indicating a broad climatic driver as opposed to localized disturbances.
To unravel the atmospheric processes underpinning these observations, Wang and colleagues examined regional circulation patterns, identifying two key factors influencing water vapor transport and precipitation delivery to the East Antarctic interior. First, an intensification of zonal winds in the upper troposphere was noted, which serves to suppress meridional (north-south) air transport toward the Antarctic continent. This wind pattern effectively limits the advection of moist air masses from lower latitudes, reducing snowfall in the typically arid interior.
Second, the study highlights the role of a deepened low-pressure system situated in the southern Indian Ocean sector. This intensified cyclonic system promotes stronger offshore winds around the Antarctic coastline, essentially acting as a barrier that pushes moisture-bearing air away from the continent’s surface. Together, these phenomena conspire to diminish the efficacy of moisture inflow, lowering the accumulation of snow and thereby contributing to the observed SMB decrease across the inland East Antarctic Ice Sheet.
These findings carry immediate and far-reaching consequences for the fields of glaciology and climate science. Foremost, they challenge the accuracy of climate and ice sheet models that have either neglected or inadequately captured these mesoscale atmospheric dynamics. By presenting concrete observational evidence of substantial mass balance decline, this study provides a critical benchmark for the refinement of model parameterizations governing atmospheric circulation, moisture transport, and surface processes.
Moreover, the documented SMB decrease suggests that prior assessments of East Antarctica’s contribution to global sea level rise may need revision. While the East Antarctic Ice Sheet has historically been viewed as relatively stable or even a net mass gain region balancing losses from West Antarctica and Greenland, the reality unveiled here implies that inland East Antarctica could be itself experiencing a net mass deficit, which would add to the vulnerabilities posed by other sectors. Such a reassessment is vital for accurately predicting future sea level trajectories under various emission and warming scenarios.
Another layer of significance lies in the adaptability of these results to inform observational strategies going forward. The effectiveness of mass balance stakes for capturing trend signals over extended timescales contrasts with the limitations inherent to satellite altimetry and gravimetry, which often face uncertainties tied to spatial resolution and temporal coverage. As such, a hybrid approach combining in situ instruments with remote sensing could yield the most comprehensive understanding of Antarctic SMB fluctuations, particularly in the context of validating and improving the spatial representativeness of satellite measurements.
The research also raises intriguing questions regarding the influence of broader climate teleconnections and atmospheric variability modes on Antarctic SMB. For instance, the role of the Southern Annular Mode (SAM), the Indian Ocean Dipole, and El Niño-Southern Oscillation in modulating the atmospheric conditions described in this study warrants further exploration. Delineating these connections could unlock predictive potential for future SMB changes under evolving climate regimes.
While this study’s focus is regional, the underlying physical principles apply across Antarctic climatic zones and could inform comparative studies, particularly in zones where surface mass balance undergoes larger interannual variability. Understanding why some areas appear resilient or even increasing in SMB, while this particular inland section declines, will refine the broader picture of Antarctic ice sheet behavior and susceptibility to climatic perturbation.
Concurrently, the role of temperature-driven melt, which on the East Antarctic Plateau is generally minimal due to pervasive cold conditions, remains a secondary factor according to the authors’ analysis. This finding underscores the primacy of precipitation changes mediated through atmospheric circulation in controlling SMB shifts inland, as opposed to thermally-driven meltwater processes more prominent at maritime Antarctic margins.
Additionally, this sustained SMB decline presents fresh considerations for interpreting ice core records. Since SMB is a key determinant of snow accumulation and stratigraphy, shifts identified in stake measurements may correlate with subtle changes in stratigraphic markers and isotope ratios archived in the ice. This alignment can help synchronize ice core dating and paleoclimate reconstructions more precisely with recent climatic trends.
Furthermore, in addressing the mechanistic drivers of atmospheric circulation, the study leverages reanalysis datasets and climate model output to corroborate observational evidence. This integrative approach bolsters confidence in attributing the SMB decline to plausible large-scale atmospheric shifts rather than isolated anomalies, and provides a template for future studies investigating cryosphere-atmosphere interactions.
Notably, the discovery that zonal wind enhancements and strengthened offshore flow collectively diminish onshore moisture delivery invites attention to the potential feedback loops in the climate system. Changes in Antarctic SMB influence albedo and energy balance at the surface, which in turn can affect atmospheric circulation patterns. Disentangling these feedbacks constitutes an essential next step for climate scientists.
To conclude, the meticulous analysis presented by Wang et al. ushers in a paradigm shift regarding the stability and evolution of East Antarctic surface mass balance. By documenting a pronounced and enduring decrease along a vast inland transect, this research not only spotlights underappreciated climatic processes but also equips the scientific community with invaluable empirical data to enhance predictive models. In the era of accelerating climate change, such nuanced understanding is critical for anticipating the Antarctic Ice Sheet’s future trajectory and ultimate impact on global sea levels.
Subject of Research: Surface mass balance trends and atmospheric circulation influences on the East Antarctic Ice Sheet between 2005 and 2020.
Article Title: Sustained decrease in inland East Antarctic surface mass balance between 2005 and 2020.
Article References:
Wang, D., Ma, H., Li, X. et al. Sustained decrease in inland East Antarctic surface mass balance between 2005 and 2020. Nat. Geosci. 18, 462–470 (2025). https://doi.org/10.1038/s41561-025-01699-z
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