Global warming has a significant impact on marine ecosystems, affecting various aspects of life in the ocean. First, increasing sea water temperatures cause changes in species distribution. Many species of fish and other marine animals move north or to greater depths to find more suitable conditions. This can cause changes in the food chain and affect fisheries yields. Second, global warming also contributes to the melting of ice in the polar regions. When the ice melts, this has a direct impact on rising sea levels and loss of habitat for ice-dependent species, such as polar bears and penguins. In addition, melting ice has an impact on ocean salinity and temperature, which in turn affects ocean current patterns. Third, global warming causes an increase in ocean acidity. Carbon dioxide gas (CO2) accumulated in the atmosphere is absorbed by the ocean, producing carbonic acid. This has a negative impact on organisms that have shells, such as coral reefs and molluscs, which require calcium carbonate for growth. A decline in the population of these organisms can disrupt the entire marine ecosystem, as they are an important part of the food chain. Fourth, coral reefs are one of the marine ecosystems most threatened by global warming. Higher temperatures lead to coral bleaching events, where corals expel the algae that gives them color and nutrition. This bleaching results in the mass death of coral reefs, which are habitat for thousands of marine species. Additionally, global warming triggers changes in weather patterns and often contributes to the frequency and intensity of tropical storms. Stronger storms could damage coastal infrastructure and add stress to maritime ecosystems. Climate change also has the potential to affect the migration and breeding of marine species. The socio-economic impact of global warming on marine ecosystems cannot be ignored. Communities that depend on fisheries for their livelihoods will feel the impact. The decline in fish populations will affect food security and the local economy. This impact also results in social tensions, considering that many countries compete to access increasingly scarce resources. In an effort to reduce the effects of global warming, the need for collective action to protect marine ecosystems is urgent. Protection of marine areas and sustainable management of fisheries can help restore ecosystems that have been affected. In addition, environmental awareness and stricter law enforcement against marine pollution are important steps. By understanding the relationship between global warming and marine ecosystems, we can be better prepared to deal with the consequences that will arise in the future. Protecting the ocean is not only important for marine life, but also for human well-being and the sustainability of our planet.