Radiosonde data from the RV Sonne cruise SO284: Tropical Atlantic Circulation and Climate: Mooring Rescue (June 27, 2021 - August 16, 2021) The dataset includes both raw data as well as post-processed products: Processing level Description Usage examples 0 mwx sounding files as delivered by Vaisalas sounding software Checking specific setup of sounding station, Archival of data 1 Level 0 data converted to netCDF4 Analysis of single soundings for the most accurate measurements possible 2 Level 1 data interpolated to a vertical grid Analysis of entire campaign or comparison with other observations or simulations A full description of the dataset and the processing scripts involved can be found in the following repository: https://github.com/observingClouds/soundings_circbrazil Soundings were conducted by H. Franke, I. Quaglia, K. Stolla and J. Windmiller. Technical support has generously been given on-board by R. Engelmann, J. Lehmke, T. Ruhtz and A. Skupin. Post-processing of the data has been done by H. Schulz. Planning of the cruise and the atmospheric measurement strategy are the work of J. Windmiller. Acknowledgment The crew of R/V Sonne greatly contributed to the success of the cruise. Financial support was provided by the German Science Foundation (DFG), by the EU H2020 under grant agreement 817578 TRIATLAS project and by the German Federal Ministry for Economic Affairs and Energy (BMWi) under grant no. 50EE1721C. We also acknowledge the public support of the conducted basic research through the Max Planck Society.