This dataset contains 268 files of basic gridded atmospheric and surface data for the planet Mars, each covering a period of 30 sols (Martian mean solar days). The fields are produced by assimilating retrieved atmospheric quantities using the Analysis Correction (AC) scheme in the UK spectral version (Oxford University and The Open University) of the Mars Planetary Climate Model (Mars-PCM), which is maintained by the Laboratoire de Météorologie Dynamique at Sorbonne Université in Paris, France.

Observations are taken from the Mars Global Surveyor/Thermal Emission Spectrometer (MGS/TES), the Mars Odyssey/Thermal Emission Imaging System (ODY/THEMIS), and the Mars Reconnaissance Orbiter/Mars Climate Sounder (MRO/MCS) instruments. Assimilated MGS/TES retrievals include nadir thermal profiles below approximately 40 km altitude and column dust optical depth values. Assimilated ODY/THEMIS retrievals include column dust optical depth values. Assimilated MRO/MCS retrievals include limb thermal profiles and dust extinction profiles below approximately 80 km altitude, as well as estimates of column dust optical depth values.

The dataset covers 12 Martian years (MY), from MY 24 through MY 35 (i.e. from July 1998 through February 2021). Each file contains 30 sols, and each sol contains variables at 12 times. TES, THEMIS, and MCS retrievals are assimilated separately, with no overlap. Several 30-sol periods at the beginning of MY 24 contain no available observations; in these cases the model is run with no assimilation (free run).

The file name and the "assimilation_run_type" global attribute indicate which observing system is assimilated in each file: MGS/TES, ODY/THEMIS, MRO/MCS, MRO/MCS_nodust (only thermal profiles, no dust extinction profiles nor column dust optical depth values), MRO/MCS_nodustprof (only thermal profiles and column dust optical depth values, no dust extinction profiles), or free-run (i.e. no assimilated observations because retrievals are not available).