June 8 is the United Nations World Oceans Day and the 2022 theme is Revitalization: Collective Action for the Ocean. This year marks the 50th anniversary of the 1972 United Nations Conference on the Environment in Stockholm, the first world conference to center the environment. Since then, most elements of nature get their own special day. Every day should be Earth Day, Environment Day and Oceans Day but designating a special occasion for each helps focus the mind.
How much do you know about our oceans and why they are so vital to life?
Ocean versus sea. The words “ocean” and “sea” are often used interchangeably but there is a difference geographically. There is one global ocean divided into five major interconnected basins: the Pacific, the Atlantic, the Indian, the Southern and the Arctic. Seas are smaller bodies of water typically located where land meets the ocean.
Why so blue? The ocean isn’t really blue. It looks blue because red, orange and yellow are absorbed more intensely. When light from the sun enters the ocean, the blue is visibly reflected. More than 70 percent of the planet is covered by oceans. That’s why the earth looks like a majestic blue orb from outer space.
A carbon sink. Tropical rainforests inhale carbon dioxide and exhale oxygen and are often called the “lungs of the planet.” But rainforests account for about 28 percent of the earth's oxygen. By comparison, thanks to ocean marine plants like phytoplankton, kelp and algal plankton, the ocean is responsible for 70 percent of the planet’s oxygen.
Photo Credit: Getty Images
Endless species. Most of the planet's biodiversity – from single-celled, microscopic organisms to the largest animal on the planet, the blue whale – is aquatic. Researchers and scientists discover thousands of marine species each year but estimate that over the vast majority have not been identified.
Wide and deep. The average depth of oceans is just over two miles. But the Mariana Trench about 200 miles southwest of Guam in the Pacific is almost seven miles deep and the water pressure is eight tons per square inch.
Underwater mountains. The longest mountain range in the world, Mid-Oceanic Ridge, stretches about 40,390 miles long; 90 percent of it is in the ocean. Much of this prominent feature remains a mystery.
The place where fire and water mix. There are million of volcanoes on the ocean floor. Ninety percent of all volcanic activity happens in the ocean, including more than 70 percent of volcanic eruptions that increase surrounding water temperatures to more than 190 degrees.
A basement filled with treasure. UNESCO estimates that 3 million wrecked vessels lie at the bottom of the ocean. Some are believed to be thousands of years old and, collectively, contain more ancient cultural artifacts than all the world’s museums combined.
NOAA estimates that more than 80 percent of the ocean has never been mapped, observed or explored in any way. Given how much we already know about the oceans, imagine much we have yet to learn.
**Cover image credit: United Nations World Ocean Day 2022
