While the Southern Hemisphere has only a few radar stations in Antarctica, weather forecasts heavily rely on satellite data and global models. This scarcity of observations creates prediction uncertainty, leading to significant errors in forecasting atmospheric rivers, corridors of water vapor capable of triggering heavy rains, floods, and strong winds thousands of kilometers away. The recent integration of Antarctic radar data, collected by the Copernicus network, provides a direct view of atmospheric dynamics above the most isolated continent on Earth.
New Antarctic radar data reduces uncertainty in atmospheric river forecasts
High-resolution radars deployed along Antarctica's coast capture cloud movements and humidity variations with unprecedented precision. By comparing these observations with ECMWF model outputs, scientists have found a decrease in prediction uncertainty of several tens of percent for atmospheric river events developing over the southern Indian Ocean. This improvement enables better tracking and intensity forecasting of water flows, particularly those headed towards Australia or New Zealand.
Radar data complements satellite measurements by providing vertical information on cloud structure, previously impossible due to the lack of ground stations. With these observations, models can adjust humidity and wind fields more rapidly, reducing forecast errors. The result is a notable reduction in the average error between precipitation forecasts and observations, improving confidence in flood risk management decisions.