Özsoy is Professor of Physical Oceanography. In 1977-1978, he served as Staff Engineer at Tetra Tech Inc., Jacksonville, FL, USA; since 1978 he has been Professor of physical oceanography at Institute of Marine Sciences, METU, Erdemli, Mersin, Turkey; following an academic and research career as Visiting Scientist at IMGA-CNR, Modena, Italy in 1989; Visiting Professor, UNESCO and Fulbright Fellow at Division of Applied Science at Harvard University, Cambridge, MA, USA in 1989-1990; Visiting Scientist at University of Bologna, Bologna, Italy in 2014-2015; Invited Professor at EIES-ITU in ¿stanbul, Turkey in 2015-2017; an Emeritus living in Ankara, Turkey after 2017.

Research interests and contributions include ocean modeling of the Levantine Basin of the Eastern Mediterranean, Black Sea, Caspian Sea, Turkish Straits System; circulation, cascading flows across shelf seas of the Eastern Mediterranean and Black Sea; dynamics, transport modelingof Bosphorus / Dardanelles Straits of the Turkish Straits System; quasi-geostrophic dynamics of seas with islands; coupled hydrodynamics-ecosystem modeling; double diffusive convection, boundary and interior mixing; operational oceanographic and atmospheric observing and forecasting systems; atmospheric transport of aerosol dust; oceanographic use of tracers for analyses of deep water renewal and transport; transport at tidal inlets; modeling of Eastern Mediterranean tsunami; climate variability and climate change /in the Seas of the Old World; history of oceanography - 17th century work of Marsili in the Bosphorus.