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JMC13 - Tropical-polar interactions under rapid climate change: Processes and influences

Centennial-Scale Variability in Antarctic Surface Mass Balance and its Linkages to Tropical Oceans

1. Kai  Man*, Institute of Atmospheric Physics Chinese Academy of Sciences,China

2. Xichen  Li, Institute of Atmospheric Physics Chinese Academy of Sciences,China

3. Wenju  Cai, Frontiers Science Center for Deep Ocean Multispheres and Earth System and Physical Oceanography Laboratory,Ocean University of China,China

4. Jurg  Luterbacher, Center for International Development and Environmental Research and Department of Geography,Justus Liebig University Giessen,Germany/Deutschland

5. David  Holland, Courant Institute of Mathematical Sciences,New York University,United States

6. Lei  Geng, School of Earth and Space Sciences,University of Science and Technology of China,China

7. Yetang  Wang, College of Geography and Environment,Shandong Normal University,China

8. Guitao  Shi, State Key Laboratory of Estuarine and Coastal Research,East China Normal University,China

9. Yonggang  Liu, Laboratory for Climate and Ocean?Atmosphere Studies,Department of Atmospheric and Oceanic Sciences,School of Physics,Peking University,China

10. Naiming  Yuan, School of Atmospheric Sciences,Sun Yat-sen University,China

11. Yurong  Hou, Institute of Atmospheric Physics Chinese Academy of Sciences,China

*Presenting Author

The Antarctic Ice Sheet is a major source of uncertainty in projections of global sea level rise. Understanding the processes governing past mass changes in the Antarctic Ice Sheet is critical for improving these projections. Past mass fluctuations are primarily driven by changes in the ice sheet's surface mass balance (SMB)?the balance between snowfall accumulation and mass loss through melting and sublimation. Using ice core measurements and reconstructed SMB data from the past centuries, we investigate the main driver of the changes in both regional and continental SMB across Antarctica. Our analysis, supported by proxy data and sea surface temperature (SST) reconstructions, identifies centennial-scale changes in tropical ocean conditions as a key contributor to Antarctic SMB variability. Numerical experiments further demonstrate that SST changes in the tropical Pacific and Atlantic significantly influence centennial to multi-centennial variability in snowfall rates over the Antarctic Ice Sheet. This tropical-polar linkage operates through atmospheric teleconnections, particularly via Rossby wave dynamics. While atmospheric teleconnections between the tropics and higher latitudes are well-documented on interannual to decadal timescales, our findings highlight the existence and importance of centennial-scale teleconnections, which have been largely absent from the existing literature. Additionally, investigations using observations and proxy data from both tropical and polar regions suggest that similar mechanisms may also operate on millennial and longer timescales.