The Earth’s oceans are a complex and dynamic system, covering over 140 million square miles and containing approximately 332.5 million cubic miles of water. They play a critical role in regulating the planet’s climate, as well as being home to a vast array of marine life and serving as a source of food, energy, and other resources for humans.

The oceans are divided into four main basins: the Pacific Ocean, which is the largest and deepest of the four; the Atlantic Ocean, which is the second-largest and separates the Americas from Europe and Africa; the Indian Ocean, which extends from the east coast of Africa to the west coast of Australia; and the Arctic Ocean, which is the smallest and shallowest of the four and is located in the polar regions.

The oceans are interconnected and are influenced by a wide range of factors, including the atmosphere, the Earth’s rotation, temperature, and the salinity of the water. They are also subject to various natural and anthropogenic (human-caused) stressors, such as climate change, overfishing, pollution, and ocean acidification, which can have significant impacts on marine ecosystems and the services they provide to humans.