The Importance of the Ocean

The ocean is a vast body of salt water that covers 70% of Earth’s surface. This water is home to a tremendous variety of plants, animals, and microscopic plankton. It also plays a key role in global weather and climate. The ocean absorbs heat and carbon dioxide from Earth’s atmosphere, distributing it more evenly over the planet. It also provides food, shelter, and transportation for many organisms.

The deep, cold currents of the ocean are important sources of oxygen for ocean organisms. These currents bring up nutrient-rich waters from the bottom of the ocean to the surface. Ocean animals take in these nutrients and use them to grow and produce food. This process is called photosynthesis. Some of the organisms that carry out this process are coral reefs, algae (seaweed), and marine plants such as seagrass.

These ocean organisms live in the epipelagic zone, the layer of the ocean just above the sandy bottom. The epipelagic zone is the area where most of the photosynthetic activity occurs in the ocean. This process is crucial for the survival of fish and other ocean organisms. The process uses sunlight and carbon dioxide to form sugars, which are then used by organisms for energy and to form oxygen. Most of this activity takes place in the tiny plants, called phytoplankton, that inhabit the epipelagic zone. The epipelagic zone is also home to other types of aquatic vegetation, including large algae such as kelp and brown, green, or red seaweed.

In addition to oxygen, the ocean produces a huge amount of food for all living things on the planet. This food comes from the phytoplankton that live in the epipelagic zone and from the marine plants that make up the reefs, seagrass beds, and algae forests. These food-producing ecosystems are a vital part of the ocean.

Some of the most diverse habitats on Earth are found in the ocean, from the rocky shores and shallow reefs of tropical seas to the cold, dark depths of the Antarctic. Oceans are filled with complex ecosystems that have adapted to the unique conditions of each region.

The chemistry of the ocean is changing rapidly. As a result of human activities, ocean acidity is increasing faster than at any time in the past 20 million years. The ocean is absorbing carbon dioxide, an invisible, odorless gas that is released into the air by burning fossil fuels and other industrial processes. The more carbon dioxide that is added to the atmosphere, the more the ocean absorbs.

National Geographic Explorer Marcello Calisti explores the ocean floor and its amazing physical features, including deep canyons and steep cliffs. He’s working to design a robot that moves like an octopus to enable exploration of the parts of the ocean that are too deep for humans to reach. Learn more about his work and the other great National Geographic Explorers here.

Scroll to top