This dataset contains high-frequency eddy covariance (EC) measurements over a flat agricultural field at the Thünen Institute in Braunschweig, Germany (52.30° N, 10.45° E). The data collection period spanned 77 days in the year 2020 split into three files BS2020_06.rds June 11 to July 15 BS2020_10.rds October 1 to November 10 BS_2020_07_subset.rds July 11 to July 25 Included in the dataset are 3D wind velocity data, recorded using a uSonic-3 Class A sonic anemometer from Metek GmbH. Additionally, the dataset provides gas concentration measurements for carbon dioxide (CO2) and water vapor (H2O), captured using an LI-7500A open-path infra-red gas analyzer from LI-COR Biosciences GmbH, Germany. Variables in the dataset Variable Name Description Units time Unique time stamp (POSIXct format) Seconds since Unix epoch CO2 Wet molar density of carbon dioxide µmol m⁻³ H2O Wet molar density of water vapor mmol m⁻³ Ts Sonic temperature Kelvin u, v, w 3D wind velocity components m s⁻¹ The dataset is in RDS format (version 3), compatible with R version 3.5.0 or higher. RDS is a binary file format native to the R programming environment