GoldOceanNT is the sea surface height field from a general circulation model of the ocean, with hourly snapshots throughout the course of a yearlong simulation. The model is the Generalized Ocean Layered Model (GOLD), performed at a nominal 1/8 degree resolution and then interpolated from the model grid to a uniform quarter-degree grid, the same grid used by the AVISO/CMEMS gridded altimetry products. The forcing includes wind and buoyancy fluxes representative of the year 2007. It differs from the parallel simulation GoldOcean in that the tidal forcing is omitted. For more details see Simmons, H.L., and M.H. Alford. 2012. Simulating the long-range swell of internal waves generated by ocean storms. Oceanography 25(2):30–41, http://dx.doi.org/10.5670/oceanog.2012.39. The image below shows the sea surface height anomaly relative to the time average at the start of the simulation.