Pedestrians and vehicles make their way past the Potala Palace early on a rainy morning in Lhasa, capital of the Tibet Autonomous Region in China, Saturday, September 19, 2015. Chinese officials have taken foreign journalists on a visit to the region, normally off-limits to them, weeks after Communist Party officials commemorated the 50th anniversary of the establishment of the Tibet Autonomous Region. (Photo by Aritz Parra/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)

A tourist crosses flooded St. Mark's Square in Venice, Italy on November 11, 2012. Flooding is common this time of year and Sunday's level that reached a peak of 58.66 inches was below the 63 inches recorded four years ago in the worst flooding in decades. (Photo by Luigi Costantini/Associated Press)

A participant stands next to a robot during the St. Petersburg International Economic Forum (SPIEF) in Saint Petersburg, Russia on June 15, 2022. (Photo by Maxim Shemetov/Reuters)

In this June 23, 2015 photo, Ashaninka Indian beauty contestants pose for a photo with members of a visiting music group, hired to perform during the annual founding anniversary festivities, in Otari Nativo, Pichari, Peru. The contestants wear the simple brown dresses of the Ashaninka woman, their faces dotted in a traditional design with a red dye extracted from a spice called achiote. (Photo by Rodrigo Abd/AP Photo)

A view of an installation part of “We Walked the Earth” by artist Uffe Isolotto at Denmark's pavilion during the 59th Biennale of Arts exhibition in Venice, Italy, Tuesday, April 19, 2022. (Photo by Antonio Calanni/AP Photo)

A boy attempts to keep a candle lit in a flooded cemetery following Typhoon Molave, in Masantol, Pampanga, Philippines, October 27, 2020. (Photo by Eloisa Lopez/Reuters)

Yakutsk, with a population of around 270,000, holds its own title: that of the coldest city on Earth. Here: Frost-encrusted house in the city centre. (Photo by Amos Chapple/Courtesy Images/RFE/RL)