GeoBasis Nuuk - Fluxmonitoring - EddyFen_2018-

The EddyFen station measures carbon dioxide- and methane fluxes via eddy covariance method in a low Arctic fen site (40 m.a.s.l) close to InteractFen (Meteorology, Soil Properties, Snow Properties; 2011-) and SoilFen (Meteorology, Soil Properties; 2007-) and the former station AutochambersFen (Flux Monitoring; 2007-2021). The station was established in 2007 and originally instrumented with a LI7000 CO2/H2O analyzer and Gill 1210R3 sonic anemometer (2007-2018). In 2018 the station was relocated a few meters and upgraded with a LI7200RS closed-path gas analyzer and a SmartFlux2 processing system (2018-). The Gill HS-50 sonic anemometer replaced the previous model in 2019 (2019-), and an LI7700 open-path CH4 Analyzer was added in 2024 (2024-). Due to the relocation in 2018, the CO2 flux time series are divided into two datasets (pre-2018 and post-2018). This dataset contains quality-controlled fluxes of CO2, LE and H; CO2- and H2O concentrations; friction velocity; wind speed and -direction from 2018 onwards. In 2021 the station was labelled ICOS (Integrated Carbon Observation System) associated, and data are processed following ICOS standards, with a logging frequency of 20 Hz and aggregated as 30-minute averages (UTC-3 West Greenlandic Winter Time). From 2007 to 2023, data were collected only during the summer field season (approximately May–October) due to winter power limitations. Since 2024, continuous year-round data collection has been enabled, though occasional data gaps remain in the dark months from November to February. Pre-2018 time series containing CO2 flux data is available under the dataset under "EddyFen" and CH4 fluxes are expected to be made available as a separate dataset soon. Fluxmonitoring:Fluxmonitoring GeoBasis Nuuk:The GeoBasis monitoring programme focuses on selected abiotic characteristics in order to describe the state of Greenlandic terrestrial environments and their potential feedback effects in a changing climate. Monitored plot data is up-scaled to a landscape level and is used to improve ecosystem models to be able to quantify these feedback mechanisms. The GeoBasis programme provides an active response to recommendations in international assessments such as ACIA and SWIPA; and is continuously being adapted based on AMAP and other international founded recommendations. Furthermore, the GeoBasis programme is directly involved in several international networks and research projects (e.g. the Circumpolar Active Layer Monitoring (CALM) programme, the Nordic Centre of Excellence DEFROST, the Danish Centre of Excellence CENPERM, the EU-projects PAGE21 and INTERACT, and the Arctic Research Centre at Aarhus University). The GeoBasis programme is divided into a number of sub-groups, including: