The Lower Atmosphere above Svalbard (LAS): Observed long term trends, small scale processes and the surface exchange

All the components of the Arctic System must be observed across time and space to understand the scope and evolution of change. Understanding how the system functions and projecting future changes requires models developed or initialised using data. For the Svalbard region, these data should primarily come from the core ESS measurements within SIOS. Long-term records of lower atmospheric variables are primarily available from six permanent observations sites in Svalbard: Longyearbyen, Barentsburg, Ny-Ålesund, Hornsund, Håpen and Bjørnøya. Bjørnøya has a climate distinct from the rest of Svalbard, and Håpen is also not representative of large parts of the archipelago. The remaining sites are all at sea level, on or near the west coast of Spitsbergen, limiting our ability to understand spatial variability across the main parts of Svalbard. Among the long-term stations, by far the most extensive atmospheric observations are made in Ny-Ålesund. This report therefore focuses on the observations, results and needs in Ny-Ålesund, while also highlighting the challenges coming from the lack of broader geographical coverage