ESA's Arctic Weather Satellite (AWS) is a novel mission to demonstrate the ability of polar-orbiting satellites to improve short-time forecasts and nowcasts of Arctic weather. Although the payload consists of a state-of-the-art microwave radiometer, the mission is designed in a cost-effective manner and, if successful, will serve as a blueprint for the Sterna constellation of satellites, which is under consideration by EUMETSAT. The AWS was launched in August 2024 and this highlight paper describes the mission, the radiometer and the state of the mission towards the end of the commissioning phase.

Laitinen et al. demonstrate the remarkable agreement between two independent greenhouse gas observation systems (GAW and ICOS) at the Pallas station in Finnish Lapland, confirming the high accuracy and reliability of long-term CO₂ and CH₄ measurements in the Northern Hemisphere. Their results strengthen confidence in atmospheric monitoring data critical for carbon cycle research.