This dataset contains monthly means of ocean and sea ice variables from a 61 year (1948-2009) integration of the GOS6 model configuration at 1degree horizontal resolution. The ocean output fields on T, U, V, and W grids are provided in separate files. The ocean component is on a 1 degree grid (eORCA1) with 75 vertical levels. The temperature and salinity fields were initialised from EN4 climatology (Good et al., 2013) and forced by the CORE2 surface dataset (Large & Yeager, 2009). All initialisation and ancillary data are also included. The outputs were generated under the UK Earth System Modelling (UKESM) project funded by the Natural Environment Research Council (NERC) under reference NE/N018036/1.