Because the ocean is actively convecting where it is near freezing, no sea ice forms during this simulation, except near the coasts. However, the ocean surface will eventually freeze (on the much longer timescales needed to cool the entire water column to freezing). It may seem surprising that no widespread sea ice forms on the night side of the planet within 50 years; after all, new sea ice forms every winter in Earth’s high latitudes. However, Earth’s polar regions currently experience net precipitation, and the fresh water effect on the ocean density allows the surface to freeze without the need for the entire column of ocean water to reach the freezing point. In contrast, the night side of the tidally locked Earth experiences net evaporation, so the ocean surface is becoming cooler and saltier, so convection penetrates deeper into the interior ocean as the simulation progresses and prevents the surface from freezing.