LAUSR

Abstract. A high-quality dataset of surface water fugacity of CO2 ( fCO2w ) 1 , consisting of over a million observations, and derived products are presented for the northern Caribbean Sea, covering the time span from 2002 through 2018. Prior to installation of automated pCO2 systems on cruise ships of Royal Caribbean International and subsidiaries, very limited surface water carbon data were available in this region. With this observational program, the northern Caribbean Sea has now become one of the best-sampled regions for pCO2 of the world ocean. The dataset and derived quantities are binned and averaged on a 1 ∘ monthly grid and are available at http://accession.nodc.noaa.gov/0207749 (last access: 30 June 2020) ( https://doi.org/10.25921/2swk-9w56 ; Wanninkhof et al., 2019a). The derived quantities include total alkalinity (TA), acidity (pH), aragonite saturation state ( ΩAr ) and air–sea CO2 flux and cover the region from 15 to 28 ∘  N and 88 to 62 ∘  W. The gridded data and products are used for determination of status and trends of ocean acidification, for quantifying air–sea CO2 fluxes and for ground-truthing models. Methodologies to derive the TA, pH and ΩAr and to calculate the fluxes from fCO2w temperature and salinity are described.