Sodankylä supersite: A key role in the European and Arctic weather prediction modelling community
The Sodankylä supersite is an observation site which is integrated into research-based infrastructures, improving observations in the Arctic region. PCAPS' work focuses on enhancing and delivering forecasts in polar regions; the Sodankylä supersite enables PCAPS to provide more accurate predictions and effectively communicate reliable data about these areas.
One of the primary objectives of the PCAPS project is to provide more accurate and reliable analyses and predictions in polar regions. A key aspect in achieving this is process-based evaluation of coupled models, which can aid model development. Multidisciplinary and comprehensive observations from supersites play a crucial role in these efforts by providing essential data for validating and improving these models.
Precipitation station and radiation tower at the Sodankylä supersite. Photo credits: Oskar Lindgren
“Supersites are sites that either have a high representativeness of a specific environment or collect a comprehensive set of multidisciplinary variables. They rely on permanent, sustained infrastructure and have (or plan to have) data infrastructures providing open access to data acquired by in-situ and satellite Earth observing systems. A single supersite can belong to several thematic networks, generally encompasses an area greater than a conventional observing platform, and is comprised of more than one active measuring platforms with varying capabilities that are operated as a coordinated unit.”
The Sodankylä supersite in northern Finland is one of very few supersites in Europe and in the Arctic providing a full characterization of surface and atmospheric parameters that affect the surface energy budget. It is the only supersite representing the boreal forest (which occupies about 17% of the Earth's land) and the Arctic mainland; the other Arctic supersites are located along the coast. Other key features of Sodankylä supersite are: 1) the distributed network of towers and stations that enable the capture of the spatial variability of the observed variables in a mixture of forests, open fields, and swamp, and 2) the state-of-art of the instrumentation and the quality and standardization of the observations.
ACCORD modellers visiting the wetland measurement site in Sodankylä, during the ACCORD workshop in September 2023. Photo credits: Oskar Landgren
The supersite has very much grown in the recent decades through the combination of sustained operational observations and research-based infrastructures, many of which get integrated into operational use after their development phase. Sodankylä is now part of numerous international observational networks: WMO Global Atmosphere Watch (GAW), WMO Global Cryosphere Watch (GCW), NASA/JPL/CalTech-led Total Carbon Column Observing Network (TCCON), European Integrated Carbon Observation System (ICOS), and GCOS Reference Upper-Air Network (GRUAN). The Sodankylä supersite also helps calibrate and validate Earth Observation satellites.
These characteristics made Sodankylä a key in-situ reference for the YOPPsiteMIP project to validate numerical weather prediction models with in-situ polar observations. Sodankylä’s observations were used to create the Merged Observatory Data Files (MODFs), which are standardized, well-documented datasets facilitating data-model intercomparison in the circumpolar Arctic. Three publications resulted from the project and were highlighted through a “success story” recently published by the Finnish Meteorological Institute (FMI). Sodankylä observations have also been operatively used by the HIRLAM and ACCORD consortia of European national meteorological services for validation of weather prediction model outputs.
Micrometeorological mast in the forest, at the Sodankylä supersite. Photo credits: Oskar Landgren
Despite the international importance and usage of the Sodankylä supersite observations, the development, management, and sustainability of the Sodankylä supersite almost entirely relies on Finnish national funding, mostly from FMI, with small occasional contributions from international space agencies and the European Union.
Given recent budget cuts in Finland, the long-term sustainability of some key observations is uncertain. Alternative, possibly international, long-term funding options should be discussed, including the possibility to apply the MODF concept to other European research stations, for example Abisko and Tarfala in Sweden.
Thumbnail photo information: Micrometeorological mast at the Sodankylä supersite. Photo credits: Oskar Landgren