GettyImages-138058528
A hawksbill sea turtle is seen swimming Jan. 15, 2012, near Lady Elliot Island, Australia. Getty Images

Wednesday is World Oceans Day, a holiday designated by the United Nations for appreciating and protecting the Earth's seas. The observance started in 1992 but became official in 2008, and this year's theme is "healthy oceans, healthy planet."

The world is 71 percent water, with four named oceans: the Arctic, Atlantic, Indian and Pacific. Some people recognize a fifth, the Southern Ocean, which is near Antarctica. More than 228,000 species live in the oceans, but experts think there could be up to 2 million science hasn't discovered yet, according to Reuters.

World Oceans Day is a chance to honor them and the water itself. Here are 13 quotes to help you do so, collected from EcoSalon, Seasky and Thought Catalog:

"To me the sea is a continual miracle; The fishes that swim — the rocks — the motion of the waves — the ships, with men in them, What stranger miracles are there?" — Walt Whitman

"I could never stay long enough on the shore; the tang of the untainted, fresh and free sea air was like a cool, quieting thought." — Helen Keller

"Don’t grow up too quickly, lest you forget how much you love the beach." — Michelle Held

“I couldn't imagine living in a state that didn't reach the ocean. It was a giant reset button. You could go to the edge of the land and see infinity and feel renewed.” — Avery Sawyer

"The waves of the sea help me get back to me." — Jill Davis

“Because there's nothing more beautiful than the way the ocean refuses to stop kissing the shoreline, no matter how many times it's sent away.” — Sarah Kay

"For whatever we lose (like a you or a me) it’s always ourselves we find in the sea." — e e cummings

"The sea lives in every one of us." — Robert Wyland

"Every time I stand before a beautiful beach, its waves seem to whisper to me: If you choose the simple things and find joy in nature’s simple treasures, life and living need not be so hard." — Psyche Roxas-Mendoza

"It's a little-appreciated fact that most of the animals in our ocean make light." — Edith Widder

"To me, the sea is like a person — like a child that I’ve known a long time. It sounds crazy, I know, but when I swim in the sea I talk to it. I never feel alone when I’m out there." — Gertrude Ederle

“It was a living thing that as as unpredictable as a great stage actor: It could be calm and welcoming, opening its arms to embrace its audience one moment, but then could explode with its stormy tempers, flinging people around, wanting them out, attacking coastlines, breaking down islands. It had a playful side too, as it enjoyed the crowd, tossed the children about, knocked lilos over, tipped over windsurfers, occasionally gave sailors helping hands; all done with a secret little chuckle.” ― Cecelia Ahern

"The voice of the sea speaks to the soul. The touch of the sea is sensuous, enfolding the body in its soft, close embrace." — Kate Chopin