“Diver in Magic Kingdom”. Green Lake (Grüner See) is located Tragöss Austria. In spring snowmelt raises the lake level about 10 meters. This phenomenon, which lasts only a few weeks covering the hiking trails, meadows, trees. The result is magical to watch diving landscapes. Photo location: Grüner See at Tragöss, Austria. (Photo and caption by Marc Henauer/National Geographic Photo Contest)

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)

Immigrants from the West Indies at Victoria Station in London, 1956. (Photo by Hulton-Deutsch Collection/CORBIS/Corbis via Getty Images)

Members of the Women's Organization to War on Styles (WOW) picket a dress shop in Berkeley, Calif., August 23, 1947, in protest to longer skirts and padded hips. They are the wives of GI students at the University of California. Left to right: Jackie Houser; Wanda Ames; Dorothy Inman; Terry Ligon; Ruth Van Arkel; Carrol Reynolds, and Barbara Carmichael. (Photo by AP Photo)

Soldier boys at Fort Dix, N.J., learn something about guns during their working hours, as they show their girlfriends at a camp dance, December 13, 1940. In front row, playing with the coin amusement gun, from left: Pvt. Tom D'Amato of West Orange; Rose Sinkewicz, behind gun site, of Trenton; Julia Ivans of Trenton, and Pvt. Vernon Landers of Kearney. Back row: Pvts. William Sargent and William Corlies of Philadelphia. (Photo by AP Photo)

Actors dressed as zombies and ghouls perform during a drive-in haunted house show by Kowagarasetai (Scare Squad), for people inside a car in order to maintain social distancing amid the spread of coronavirus, at a garage in Tokyo, Japan on July 3, 2020. (Photo by Issei Kato/Reuters)

Police detain a woman during a protest against Prime Minister Benjamin Netanyahu and his government's handling of the coronavirus disease (COVID-19) crisis, near Netanyahu's residence in Jerusalem on July 24, 2020. Reimposed coronavirus curbs after a rise in new COVID-19 cases have prompted Israelis demanding better state aid to take to the streets in almost daily demonstrations. Public anger has also been fueled by corruption alleged against Netanyahu, who went on trial in May for bribery, fraud and breach of trust – charges he denies. (Photo by Ammar Awad/Reuters)

A Sudanese woman repairs damages to her house, after torrential rain lead to landslides and flash floods, in the town of Umm Dawan Ban, southeast of the capital Khartoum on August 2, 2020. (Photo by Ashraf Shazly/AFP Photo)