Christian pilgrims from Brazil embrace after they are baptized in the water of the Jordan River during a ceremony at the Yardenit baptismal site near the northern Israeli city of Tiberias October 15, 2014. (Photo by Finbarr O'Reilly/Reuters)

The Bajau people of Malaysia live their lives completely at sea, living in wooden huts and spending their days fishing. Sailing over crystal clear waters, the Bajau people of Malaysia live their lives almost entirely at sea. Photographer Ng Choo Kia joined the Bajau people on their pirogues, which are long narrow canoes made from single tree trunks, and documented their daily life in a series of pictures. (Photo by Ng Choo Kia/Hotspot Media/SIPA Press)

A man (2nd L) takes pictures as visitors run away from a wave caused by a tidal bore which surged past a barrier on the banks of Qiantang River, in Hangzhou, Zhejiang province August 14, 2014. (Photo by Reuters/Stringer)

Kurt Arrigo is Malta’s most eminent and one of the world’s finest marine photographers. ­­His illustrious and diverse career has seen him capture dramatic action at elite international sporting events.

Deadwood is pictured in the onetime spa and resort town Epecuen, November 5, 2015. Over the past few years the town of Epecuen, located 550 km (341 miles) southwest of Buenos Aires, has been attracting tourists with its eerie apocalyptic atmosphere after a flood submerged it in salt water for more than two decades. Photo by Enrique Marcarian/Reuters)

Stunning images taken by Sean Lenz, 19, and Kristoffer Abligaard, 20, show picturesque waterfalls transformed into vibrant rainbows of colour. The awe-inspiring images were created by clever use of long exposure photography and glow sticks floating through water. Photo: Picturesque waterfalls transformed into rainbows of colour. (Photo by Sean Lenz/Kristoffer Abildgaard)

Growing cities, overuse of fertilizers and factory wastewater have degraded China's water supplies to the extent that half the nation's rivers and lakes are severely polluted. China aims to spend $850 billion to improve filthy water supplies over the next decade, but even such huge outlays may do little to reverse damage caused by decades of pollution and overuse in Beijing's push for rapid economic growth. Photo: Fishermen row a boat in the algae-filled Chaohu Lake in Hefei, Anhui province, June 19, 2009. (Photo by Jianan Yu/Reuters)