Interannual variations associated with El Niño-Southern Oscillation can alter the surface-pressure distribution and moisture transport over Antarctica, potentially affecting the contribution of the Antarctic ice sheet to sea level. Here, we combine satellite gravimetry with auxiliary atmospheric data sets to investigate interannual ice-mass changes during the extreme 2015-2016 El Niño. Enhanced precipitation during this event contributed positively to the mass of the Antarctic Peninsula and West Antarctic ice sheets, with the mass gain on the peninsula being unprecedented within GRACE's observational record. Over the coastal basins of East Antarctica, the precipitation-driven mass loss observed in recent years was arrested, with pronounced accumulation over Terre Adélie dominating this response. Little change was observed over Central Antarctica where, after a brief pause, enhanced mass-loss due to weakened precipitation continued. Overall, precipitation changes over this period were sufficient to temporarily offset Antarctica's usual (approximately 0.4 mm yr −1 ) contribution to global mean sea level rise.Plain Language Summary Given that the Antarctic Ice Sheet has the potential to raise sea level by over 50 m if completely melted, it is crucial that we fully understand the factors controlling its stability. Presently, changes in rates of mass loss and mass gain over the ice sheet vary from short (seasonal/ interannual) to long (decadal) timescales. Previous research has shown that one potential factor influencing Antarctica on interannual timescales is the El Niño-Southern Oscillation, a large-scale interaction between the Pacific Ocean and the overlying atmosphere that fluctuates between warm (El Niño) and cold (La Niña) states every 2-7 years. Here, we show an unprecedented increase in accumulation over the Antarctic Peninsula and West Antarctic sectors during the extreme 2015-2016 El Niño, along with a brief stabilization in mass loss over East Antarctica. Overall, precipitation changes during this event were sufficient to temporarily offset Antarctica's usual (approximately 0.4 mm yr −1 ) contribution to global mean sea level rise.As the dominant and most far-reaching mode of interannual climate variability, the impact of ENSO on the AIS is of particular interest. El Niño's influence in the Southern Hemisphere's high latitudes has been associated with blocking events induced by Rossby wave trains that alter surface-pressure distribution and

Abstract. Over the past 50 years, the British Antarctic Survey (BAS) has been one of the major acquirers of aerogeophysical data over Antarctica, providing scientists with gravity, magnetic, and radar datasets that have been central to many studies of the past, present, and future evolution of the Antarctic Ice Sheet. Until recently, many of these datasets were not openly available, restricting further usage of the data for different glaciological and geophysical applications. Starting in 2020, scientists and data managers at BAS have worked on standardizing and releasing large swaths of aerogeophysical data acquired during the period 1994–2020, including a total of 64 datasets from 24 different surveys, amounting to ∼ 450 000 line-km (or 5.3 million km2) of data across West Antarctica, East Antarctica, and the Antarctic Peninsula. Amongst these are the extensive surveys over the fast-changing Pine Island (BBAS 2004–2005) and Thwaites (ITGC 2018–2019 & 2019–2020) glacier catchments, and the first ever surveys of the Wilkes Subglacial Basin (WISE-ISODYN 2005–2006) and Gamburtsev Subglacial Mountains (AGAP 2007–2009). Considerable effort has been made to standardize these datasets to comply with the FAIR (findable, accessible, interoperable and re-usable) data principles, as well as to create the Polar Airborne Geophysics Data Portal (https://www.bas.ac.uk/project/nagdp/, last access: 18 July 2022), which serves as a user-friendly interface to interact with and download the newly published data. This paper reviews how these datasets were acquired and processed, presents the methods used to standardize them, and introduces the new data portal and interactive tutorials that were created to improve the accessibility of the data. Lastly, we exemplify future potential uses of the aerogeophysical datasets by extracting information on the continuity of englacial layering from the fully published airborne radar data. We believe these newly released data will be a valuable asset to future glaciological and geophysical studies over Antarctica and will significantly extend the life cycle of the data. All datasets included in this data release are now fully accessible at https://data.bas.ac.uk (British Antarctic Survey, 2022).

The West Antarctic Ice Sheet (WAIS) has been losing mass at an accelerating rate since satellite records began, averaging 94 ± 27 Gt yr -1 of mass loss since 1992 (Shepherd et al., 2018). Approximately 40% of this loss was through Pine Island Glacier (PIG), which alone has contributed ∼3 mm of the total ∼7 mm sea-levelrise contribution of the WAIS between 1979(Rignot et al., 2019. The increasing mass-loss trend of PIG has been primarily driven by interannual and decadal-scale atmospheric and oceanic forcing, triggering grounding-line retreat and consequent inland dynamical adjustments (