This product corresponds to a REP L4 time series of monthly global reconstructed surface ocean pCO2, air-sea fluxes of CO2 and pH and associated uncertainties. The original datasets covered the surface ocean gridded at a spatial resolution of 1° and have been downscaled onto 0.25° since 2023. The product is obtained from an ensemble-based forward feed neural network approach (Chau et al; 2022, 2024ab) mapping situ data for surface ocean fugacity (SOCAT database, Bakker et al. 2016, https://www.socat.info/) and sea surface salinity, temperature, sea surface height, chlorophyll a, mixed layer depth and atmospheric CO2 mole fraction. Sea-air flux fields are computed from the air-sea gradient of pCO2 and the dependence on wind speed of Wanninkhof (1992). Surface ocean pH on total scale is then computed from surface ocean pCO2 and reconstructed surface ocean alkalinity using the CO2sys speciation software. This document presents approaches and tools used to produce and validate the Global Ocean Surface Carbon Product MULTIOBS_GLO_BIO_CARBON_SURFACE_REP_015_008.