Participants take part in a New Year's Jump into the Sea in Portoroz , Slovenia, January 1, 2016. (Photo by Srdjan Zivulovic/Reuters)

People play on a beach along the Arabian Sea on a hot summer day in Mumbai, India, April 29, 2016. (Photo by Danish Siddiqui/Reuters)

Waves hit the seawall during heavy seas and high winds in Dawlish in south west Britain, February 2, 2017. (Photo by Toby Melville/Reuters)

Tourists walk as others relax on the beach in the Red Sea resort of Hurghada, Egypt, July 17, 2017. (Photo by Gleb Garanich/Reuters)

Sea lion “Jay” paints a Chinese character reading “the Serpent” at the Hakkeijima Sea Paradise aquarium in Yokohama, suburban Tokyo on January 3, 2013. The event, marking the forthcoming Chinese lunar calender year of the snake was held as part of a New Year's attraction. (Photo by Kazuhiro Nogi/AFP Photo)

St Andrews University students skinny dip in the sea as May Day celebrations in St Andrews, Scotland on April 30, 2017. Hundreds of revellers ditched their clothes and bravely jumped into the bitterly cold North Sea. (Photo by Alamy Stock Photos)

This image provided by NASA shows parts of Europe and Africa very easily recognizable in this night time image shot by one of the Expedition 25 crew members aboard the International Space Station flying 220 miles above Earth on Thursday October 28, 2010. The view “looks” northward over Sicily and the “boot” of Italy, with the Mediterranean Sea representing most of the visible water in the view and the Adriatic Sea to the right of center. Tunisia is partially visible at left. Part of a docked Russian spacecraft and other components of the ISS are in the foreground. (Photo by AP Photo/NASA)