This version 4.1 MUSICA IASI / RemoTeC TROPOMI fused methane data set contains total (ground – top of atmosphere, variable ), tropospheric (ground – 50% ground pressure, variable ), and UTS (upper tropospheric/ stratospheric, 50% ground pressure – top of atmosphere, variable ) column-averaged dry-air mole fractions of methane (CH4). The data are obtained by combining the level 2 CH4 profiles and XCH4 total columns (generated from the IASI TIR spectra and the TROPOMI NIR/SWIR spectra, respectively). The level 2 CH4 profiles were generated by the MUSICA processor (version 3.2 and 3.3, Schneider et al., 2022, https://doi.org/10.5194/essd-14-709-2022) and the level 2 XCH4 total columns by the RemoTeC processor (internal SRON version 19/0446, Lorente et al. 2022, https://doi.org/10.5194/amt-16-1597-2023). The combination is realized by means of a Kalman filter that uses the MUSICA IASI data as the background and the TROPOMI data as the new observation. Details of the combination method, the IASI and TROPOMI collocation requirements, and the data quality are described in Schneider et al. (2022, https://doi.org/10.5194/amt-15-4339-2022). The data cover the 42 months from January 2018 – June 2021. The characteristics of the data set is described in detail and recommendations about data usage are given in Shahzadi et al. 2026 (https://doi.org/10.5194/essd-2025-407, final version accepted in February 2026). The full data set consists of 1241 individual netcdf file (one file per day of observation). This data package contains two example files (for 1 January and 1 July 2018: "SYNERGY_IASIMUSICA_TROPOMIRemoTeC_CH4_v0401_20180101.nc" and "SYNERGY_IASIMUSICA_TROPOMIRemoTeC_CH4_v0401_20180701.nc") and gives information on the availability of the full data set ("ReadMe.pdf").

Metop IASI, Sentinel-5 Precursor TROPOMI