In this two photo combination picture, the Eiffel Tower with its usual lighting at left, and after the lighting was switched off at right, at the occasion of the Earth Hour, in Paris, France, Saturday March 28, 2015. This Saturday, 28 March 8:30 p.m. local time, individuals, businesses, cities and landmarks around the world are switching off their lights for one hour to focus attention on climate change. (Photo by Remy de la Mauviniere/AP Photo)

In this May 4, 2014 photo, a miner holds an amalgam of mercury and gold he mined after working a 28-hour shift at an illegal gold mining process, in La Pampa, in Peru's Madre de Dios region. Thousands of artisanal gold miners sweat through the long shifts and endure, for a few grams of gold, the perils of collapsing earth, limb-crushing machinery and the toxic mercury used to bind gold flecks. (Photo by Rodrigo Abd/AP Photo)

A “Maya” girl sits in an altar during the traditional celebration of “Las Mayas” on the streets in Madrid, Spain Sunday, May 10, 2015. The festivity of the Maya comes from pagan rites and dates from the medieval age, appearing in ancient documents. It takes place every year in the beginning of May and celebrates the beginning of the spring. Girls between 7 and 11 years old are chosen as “Maya” and should sit still, serious and quiet for a couple of hours in altars on the street decorated with flowers and plants and afterwards they walk to the church with their family where they attend a ceremony. (Photo by Daniel Ochoa de Olza/AP Photo)

A Raramuris indigenous woman takes part in the “Ultra maraton de los Canones 2017” (Ultra marathon of the Canyons), at La Sinforosa Canyon, in Guachochi, Chihuahua state, Mexico on July 15, 2017. More than 600 participants from different countries take part in the 63 and 100 kilometers races, along the Tarahumara mountain range. (Photo by Herika Martinez/AFP Photo)

A woman reacts after she was hit with pepper spray deployed by police as they cleared a street with protesters rallying against a new national security law in Hong Kong on July 1, 2020, on the 23rd anniversary of the city's handover from Britain to China. A man found in possession of a Hong Kong independence flag became the first person to be arrested under Beijing's new national security law for the city, police said on July 1. (Photo by Dale De La Rey/AFP Photo)

Arrow sports his new elastic booties at a PetSmart in Tempe, Ariz. on Tuesday, June 20, 2017. Phoenix radio station KSLX handed out the protective coverings to protect dogs' paws from the hot pavement, as temperatures in Phoenix are forecasted to hit 120 degrees (48°C). (Photo by Angie Wang/AP Photo)

Filipinos cross a swelling river in Las Pinas city, south of Manila, Philippines, 09 July 2015. According to the Philippines State weather forecast, heavy rainfall is expected in Metro Manila and nearby provinces due to an enhanced Southwest Monsoon and Tropical Storm Linfa, Typhoon Chan-hom and Typhoon Nangka which are lining up across the Pacific Ocean. (Photo by Francis R. Malasig/EPA)

David Pena poses for a photograph with his Lada 2101 built in 1979 on a street in Havana February 9, 2015. Getting parts from the United States is cheaper than in Cuba, where state-run stores sell them at four times the cost, said Pena, a mechanic and president of the Russian Car Club in Havana who drives a souped-up, sporty red 1972 Lada 2101 that he fixed himself. His own Lada has a Fiat engine and an extra Alfa Romeo carburetor. (Photo by Enrique De La Osa/Reuters)