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Abstract

The South Shetland Islands (SSIs) region, located on the northern Antarctic Peninsula (AP), is influenced by different climatic configurations from regional (five atmospheric circulation patterns, sea ice extent-concentration and surface temperature) to global (Southern Annular Mode-SAM, El Niño-Southern Oscillation-ENSO and deep convection in the central tropical Pacific-CPAC) scales. However, few studies have been developed to assess the influence of these climatic conditions on the surface mass balance (SMB) of glaciers located in the SSIs. To fill this gap, we analyzed correlation between annual SMB, reconstituted with a physical surface energy balance model (COSIPY), and regional-global climate indices from 1970 to 2020. COSIPY was calibrated and validated with 19 years of annual SMB observations from three glaciers (Johnsons, Hurd and Bellinghausen), showing a good ability to capture inter-annual (R² = 71%) variability. Results showed a break in the annual SMB trend following the warming and cooling periods of the surface air temperature in the AP. In addition, our results indicated low dependence of the SMB with main global atmospheric variability (SAM, ENSO and CPAC) and high dependence with custom regional climate indices (Drake Passage, Amundsen–Bellingshausen and Weddell regions). This study highlights the Drake Passage as a key region that has the potential to influence the interannual variability of the SMB and other climate variables such as surface air temperature and snowfall in the SSIs. We suggest that future work should consider this region to better understand the past, present and future climate changes on the SSIs and surrounding areas.