Group for ocean and sea climate modeling at IO RAS was created in 2007. Its main goal is to study the hydrodynamic processes in the World Ocean and the internal seas of Russia (Caspian and Black) using high-resolution models of ocean dynamics on massively parallel computers. Over the past years, we have developed new areas of research, namely, the development of supercomputer methods for assimilating large amounts of data for highly accurate ocean forecast, as well as research on the development of a joint atmosphere — ocean — sea-ice model for studying Earth climate changes and weather forecasts. Great attention in the organization of research is given to working with talented undergraduate and graduate students from leading universities.