This directory contains the MITgcm ECCOv4-TM simulation output used in "Changes in oceanic radiocarbon and CFCs since the 1990s" (Lester et al., 2023) submitted to the Journal of Geophysical Research: Oceans. Ocean tracer simulations were created using transports matrices (TMs) derived from state estimates from the Estimating the Climate and Circulation of the Ocean version 4 (ECCOv4) based on a global configuration of the MITgcm model (MITgcm ECCOv4-TM). The monthly-mean TMs and the transport matrix method was used to simulate CFC-11, CFC-12 and abiotic DIC and 14C in DIC. CFC concentrations were converted to partial pressures (pCFC) by dividing by their solubility functions. Output is provided as Matlab .mat files. Files are named as MITgcm_ECCOv4TM_XXX.mat, where XXX is one of D14C, DIC14, DIC, pCFC11 and pCFC12 and contains annual mean fields for: Delta-14C [per mil], DIC14 concentration [mol/m3], DIC concentration [mol/m3], pCFC-11 concentration [ppt] and pCFC-12 concentration [ppt] respectively. For full details about the simulations and results see Lester et al. (2023).