This dataset includes measurements of partial pressure of carbon dioxide (pCO2), sea surface salinity, sea surface temperature and other parameters from the OceansAlaska Shellfish Hatchery in Ketchikan, Alaska since 2016-08-29. The OceansAlaska Shellfish Hatchery in Ketchikan, is a floating barge that has been a site for high-resolution measurement of surface seawater CO2 content since August 2016. Measurements of in situ temperature, salinity, and CO2 partial pressure are made near-continuously from a seawater sample line with an intake depth of 4.3 m. The effort to collect these data is a collaboration between OceansAlaska, the UAF Ocean Acidification Research Center, Oregon State University, and the Hakai Institute with support from the Alaska Ocean Observing System and the Tula Foundation.