Antarctic Greening and Its Drivers

Despite increasing interest, the spatiotemporal dynamics and drivers of Antarctic greenness remain unclear. Using 22 years of satellite data (2002-2023), we provide the first continent-wide assessment, revealing a rise in greenness from 7,356 to 11,219 km²-equivalent pixels and a lengthening of the mean annual greenness duration from 22.6 to 32.4 days. Contrary to conventional assumptions, declining ultraviolet radiation and rising soil moisture, rather than temperature, are the dominant continental-scale drivers. Notably, the reduction in UV radiation, which shapes the current pattern of greenness across Antarctica, is itself a result of global anthropogenic intervention, reflecting the success of international efforts like the Montreal Protocol to repair the ozone layer. Regionally, greenness is shaped by habitat availability in East Antarctica and by interacting climate factors in the Antarctic Peninsula. These results highlight that Antarctic greening stems from diverse, biogeographic region-specific processes and offer a baseline for monitoring future change in this uniquely important continent.