OpenADB: DGFI-TUM's Open Altimeter Database

For more than three decades, satellite altimetry has provided valuable measurement data for the monitoring and analysis of ocean and inland water surfaces. Since 1992, there have always been at least two simultaneous missions providing continuous measurement data, starting with TOPEX/Poseidon and ERS-1 in the early 1990s and continuing with about 10 satellites active today, including ICESat-2, Sentinel-6A and SWOT. Most mission data are freely available, but in different formats, processing levels and with respect to different references (e.g. ellipsoid or time), making common multi-mission applications difficult. In addition, the derivation of ready-to-use and high-quality scientific products requires expertise that not every user is willing to acquire. Over the years, DGFI-TUM has developed and maintained an Open Altimeter Database (OpenADB) that allows consistent data management and combination. It consists of the internal Multi-Version Altimetry (MVA) data repository and the OpenADB web portal. OpenADB provides user-friendly access to derived along-track products, such as sea surface heights and ocean tides. It also provides general information about the satellite altimetry missions, their observing configurations and about the data provided in the database. All products are freely available on the OpenADB web portal (https://openadb.dgfi.tum.de) after registration.