The Antarctic Ice Sheet (AIS) is out of equilibrium with the current anthropogenic‐enhanced climate forcing. Paleo‐environmental records and ice sheet models reveal that the AIS has been tightly coupled to the climate system during the past, and indicate the potential for accelerated and sustained Antarctic ice mass loss into the future. Modern observations by contrast suggest that the AIS has only just started to respond to climate change in recent decades. The maximum projected sea level contribution from Antarctica to 2100 has increased significantly since the IPCC 5^th Assessment Report, although estimates continue to evolve with new observational and theoretical advances. This review brings together recent literature highlighting the progress made on the known processes and feedbacks that influence the stability of the AIS. Reducing the uncertainty in the magnitude and timing of the future sea‐level response to AIS change requires a multi‐disciplinary approach that integrates knowledge of the interactions between the ice sheet, solid Earth, atmosphere, and ocean systems, and across timescales of days to millennia. We start by reviewing the processes affecting AIS mass change, from atmospheric and oceanic processes acting on short timescales (days‐decades), through to ice processes acting on intermediate timescales (decades‐centuries) and the response to solid Earth interactions over longer timescales (decades‐millennia). We then review the evidence of AIS changes from the Pliocene to the present, and consider the projections of global sea‐level rise, and their consequences. We highlight priority research areas required to improve our understanding of the processes and feedbacks governing AIS change.

The second generation Antarctic magnetic anomaly compilation for the region south of 60°S includes some 3.5 million line‐km of aeromagnetic and marine magnetic data that more than doubles the initial map's near‐surface database. For the new compilation, the magnetic data sets were corrected for the International Geomagnetic Reference Field, diurnal effects, and high‐frequency errors and leveled, gridded, and stitched together. The new magnetic data further constrain the crustal architecture and geological evolution of the Antarctic Peninsula and the West Antarctic Rift System in West Antarctica, as well as Dronning Maud Land, the Gamburtsev Subglacial Mountains, the Prince Charles Mountains, Princess Elizabeth Land, and Wilkes Land in East Antarctica and the circumjacent oceanic margins. Overall, the magnetic anomaly compilation helps unify disparate regional geologic and geophysical studies by providing new constraints on major tectonic and magmatic processes that affected the Antarctic from Precambrian to Cenozoic times.

Curie depths beneath Greenland are revealed by spectral analysis of data from the World Digital Magnetic Anomaly Map 2. A thermal model of the lithosphere then provides a corresponding geothermal heat flux map. This new map exhibits significantly higher frequency but lower amplitude variation than earlier heat flux maps and provides an important boundary condition for numerical ice‐sheet models and interpretation of borehole temperature profiles. In addition, it reveals new geologically significant features. Notably, we identify a prominent quasi‐linear elevated geothermal heat flux anomaly running northwest–southeast across Greenland. We interpret this feature to be the relic of the passage of the Iceland hotspot from 80 to 50 Ma. The expected partial melting of the lithosphere and magmatic underplating or intrusion into the lower crust is compatible with models of observed satellite gravity data and recent seismic observations. Our geological interpretation has potentially significant implications for the geodynamic evolution of Greenland.

The Alfvén wave mode transmits field‐aligned currents and large‐scale turbulence throughout Jupiter's magnetosphere. Magnetometer data from the Juno spacecraft have provided the first observations of Alfvénic fluctuations along the polar magnetic flux tubes connected to Jupiter's main auroral oval and the Jovian satellites. Transverse magnetic field perturbations associated with Io are observed up to ~90° away from main Io footprint, supporting the presence of extended Alfvénic wave activity throughout the Io footprint tail. Additional broadband fluctuations measured equatorward of the statistical auroral oval are composed of incompressible magnetic turbulence that maps to Jupiter's equatorial plasma sheet at radial distances within ~20 R_J. These fluctuations exhibit a k_|| power spectrum consistent with strong magnetohydrodynamic turbulence. This turbulence can generate up to ~100 mW/m² of Poynting flux to power the Jovian aurora in regions connected to the inner magnetosphere's central plasma sheet.

The Southern Ocean paleoceanography provides key insights into how iron fertilization and oceanic productivity developed through Pleistocene ice-ages and their role in influencing the carbon cycle. We report a high-resolution record of dust deposition and ocean productivity for the Antarctic Zone, close to the main dust source, Patagonia. Our deep-ocean records cover the last 1.5 Ma, thus doubling that from Antarctic ice-cores. We find a 5 to 15-fold increase in dust deposition during glacials and a 2 to 5-fold increase in biogenic silica deposition, reflecting higher ocean productivity during interglacials. This antiphasing persisted throughout the last 25 glacial cycles. Dust deposition became more pronounced across the Mid-Pleistocene Transition (MPT) in the Southern Hemisphere, with an abrupt shift suggesting more severe glaciations since ~0.9 Ma. Productivity was intermediate pre-MPT, lowest during the MPT and highest since 0.4 Ma. Generally, glacials experienced extended sea-ice cover, reduced bottom-water export and Weddell Gyre dynamics, which helped lower atmospheric CO₂ levels.