Oceans cover 70 percent of Earth’s surface and make life on the planet possible. They are also crucial to the carbon cycle-how carbon moves between air, land, and water.
There’s a lot of work going on in the world’s oceans to keep them healthy and safe. Some of that work involves cleaning up plastic waste, helping to maintain stable fish stocks, and reducing the amount of nutrient pollution in our waters.
Many people rely on the ocean for food, transportation, and recreation. The ocean also provides important natural resources, such as heat and oxygen.
The ocean has been around for millions of years, and it’s home to a huge variety of plants and animals. The ocean contains more living biomass than the rest of the planet combined. In fact, a single square mile of the ocean can hold more biodiversity than the entire continent of Africa.
Oceans are complex, but we know a lot about them. Scientists have mapped the ocean floor and discovered dramatic physical features, including canyons, mountains, and wide plains. We have even learned how the ocean is changing over time.
For example, when scientists measure how much carbon dioxide is in the ocean, they use an instrument called a CO2 analyzer. This device measures the amount of carbon dioxide in seawater and can tell whether the gas is rising or falling. Scientists also know that the ocean is a major reservoir of heat. It slowly warms in the summer and cools in the winter. This helps to stabilize the climate, keeping temperatures in coastal cities small and preventing the cold winters experienced by people who live far from the coast.
Another way the ocean affects the atmosphere is through ocean currents. Predictable wind patterns, such as predictable trade winds blowing from the east above the equator, cause surface currents to move westward. But as these currents approach the poles, they are deflected by the rotation of Earth. This is known as the Coriolis effect. The result is that currents that would normally go straight north veer to the right in the northern hemisphere and flow south in the southern hemisphere.
Scientists are concerned that global warming might disrupt the global conveyor belt. If too much carbon dioxide dissolves in the ocean, it will cause the salty, dense water at the surface to become less salty and denser. That will make it harder for this water to sink into the deeper layers, where it keeps the global conveyor belt in motion.
Phytoplankton, microscopic algae and plants that photosynthesize, live in the ocean’s epipelagic zone. These tiny organisms are key players in ocean food webs. Almost all larger marine life eats these plants and algae, or the tiny drifting animals called zooplankton that consume them. These microorganisms help to regulate ocean levels of carbon dioxide by storing carbon in their shells as they grow. The ocean is the largest carbon store on Earth. This cycle makes it very important for regulating Earth’s climate.