This chapter examines the potential influence of anthropogenic climate change on marine ecosystems and their biodiversity. The increase in CO2 concentration associated with other anthropogenic greenhouse gases such as methane and nitrous oxide has perturbed the planet's radiative budget. Global change is probably the result, of the increase in human population. The chapter shows how such a large and rapid climate change will alter current marine biodiversity. It explains the impact of the tropical cyclone Oli on Polynesian coral reefs and presents a meta-analytical study conducted in the Caribbean for the period 1980-2001 that revealed that coral reef cover decreased by about 17" on average the year after it had been hit by a hurricane. This study also suggested that steno ecious species, composing much of the earth's biodiversity, may lack genetic variability to extend the amplitude of their ecological niche and might be more vulnerable to extinction. The chapter illustrates potential peturbations of the predator-prey interactions by climate change.