Interior Antarctica is undergoing marked climate change

2024 is the warmest year in NASA’s 145-year climate record. Unlike the Arctic, which has experienced significantly faster warming than the global average, Antarctic temperature change is variable. Here we employ our observational reconstruction to show that although Antarctica has experienced warming on average, the long-term temperature trends exhibit notable spatial structure and reveal major disparities with CMIP6 models. Specifically, long-term observed warming is found in the Antarctic Peninsula and West Antarctica, with modest cooling in parts of East Antarctica, particularly during austral autumn and winter. CMIP6 substantially overestimates the Antarctic warming similar to the global rate and maximizes over the Antarctic interior. However, average and extreme temperature observations demonstrate that interior Antarctica is experiencing marked climate change, paralleling the projected CMIP6 behavior but with reduced magnitude. Elsewhere climate change is happening in the northern Antarctic Peninsula and coastal West Antarctica but is muted along the East Antarctic coast. Interior Antarctica is nearing major climate change while the northern Antarctic Peninsula and coastal West Antarctica are already experiencing it, according to observational reconstructions and model simulations.