Inorganic carbon and total alkalinity at the Western Channel Observatory from the L4 site from 2008 to 2014.

Dissolved inorganic carbon and total alkalinity measurements sampled from station L4, part of the Western Channel Observatory, and analysed at Plymouth Marine Laboratory. These measurements, together with temperature, salinity, total phosphate and silicate, are used to calculate additional carbonate system parameters (pH, pCO2, saturation states of calcite and aragonite, HCO3- and CO32-) using the programme CO2sys [Pierrot et al 2006], with dissociation constants from [Mehrbach et al. 1973] refit by [Dickson and Millero 1987] and for KSO4 from [Dickson 1990]. Measurements were initially collected by PML for the DEFRApH project (2008-2010) and were continued as part of NERC National Capability as time-series monitoring at the Western Channel Observatory.