A house along Hoover Beach is covered by ice from high winds and from the waves from Lake Erie, Saturday, February 29, 2020, in Hamburg N.Y. Blowing snow has fallen around the state since Thursday, though the heaviest snowfall was concentrated in largely rural areas east of Lake Erie and Lake Ontario. (Photo by Jeffrey T. Barnes/AP Photo)

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)

An illuminated Christmas tree leans against the window of a damaged house in Mayschoss in the Ahrtal valley, southern Germany, Tuesday, December 14, 2021. The region was hit by floodings exactly five months ago, causing the death of about 180 people. Amid the mud and debris still clogging the streets from last summer's devastating floods, residents of the Ahr Valley in western Germany are trying to spark some festive cheer with Christmas trees. (Photo by Michael Probst/AP Photo)

Lake Baikal is the world's oldest lake, at 25 million years (possibly older), and deepest, averaging 744.4 metres (2,442 ft).

Located in the south of the Russian region of Siberia, between Irkutsk Oblast to the northwest and the Buryat Republic to the southeast, it is the most voluminous freshwater lake in the world, containing roughly 20% of the world's unfrozen surface fresh water.

A male green anole lizard flares his throat fan in a backyard in Cary, North Carolina on April 27, 2021. This pink section is actually a thin flap of skin that hangs down below the green anole's throat. Anoles are renowned for their displays in which they do pushups, bob their heads up and down, and unfurl their colorful dewlaps. The male anole uses it for two primary purposes: to protect his territory and attract a mate. (Photo by Bob Karp/ZUMA Press Wire/Alamy Live News)

Brain-on-a-chip. Dazzling in green and magenta this image shows the nerve fibres (in green) produced by neural stem cells (in magenta) as they grow on a synthetic gel. Captured by a technique known as confocal microscopy, the image is part of research shedding light on how tinkering with the environment can affect the way in which nerve fibres grow. (Photo by Collin Edington and Iris Lee/Massachusetts Institute of Technology/Wellcome Images)

A farmer harvests tobacco leaves at a plantation in the valley of Vinales, in the western Cuban province of Pinar del Rio, January 27, 2015. (Photo by Pilar Olivares/Reuters)

Women take a photo in the late afternoon sun during the Coachella Valley Music and Arts Festival on April 17, 2017 in Indio, California. (Photo by Carlo Allegri/Reuters)