Engine driver Josef Kowatsch (top L) steers a train through the NEAT Gotthard Base Tunnel during a media visit near the town of Erstfeld August 24, 2015. Crossing the Alps, the world's longest train tunnel should become operational at the end of 2016, consisting of two parallel single track tunnels, each of a length of 57 km (35 miles). (Photo by Arnd Wiegmann/Reuters)

This photo provided by Netflix/naturepl.com and WWF-International shows an African Elephant (Loxodonta africana) in front of double rainbow, in Masai Mara, Kenya, included in the Netflix natural history series, “Our Planet”, in collaboration with Silverback Films and WWF. The eight-part series debuts in 2019. (Photo by Andy Rouse/Naturepl/WWF-International/Netflix via AP Photo)

Locals harvest their potatoes as Mount Sinabung spews volcanic ash in Karo, North Sumatra province, Indonesia on August 10, 2020. (Photo by Sastrawan Ginting/Antara Foto via Reuters)

Bangladeshi people walk in a polluted air environment in Dhaka, Bangladesh on September 3, 2020. A study says, air pollution shortens life expectancy by seven years in Bangladesh. (Photo by Sultan Mahmud Mukut/SOPA Images/Rex Features/Shutterstock)

Zhou Xiaoxuan, center, weeps as she speaks to her supporters upon arrival at a courthouse in Beijing, Wednesday, December 2, 2020. Zhou, a Chinese woman who filed a sexual harassment lawsuit against a TV host, told dozens of cheering supporters at a courthouse Wednesday she hopes her case will encourage other victims of gender violence in a system that gives them few options to pursue complaints. (Photo by Andy Wong/AP Photo)

People play with toy guns outside a bar at night, almost a year after the global outbreak of the coronavirus disease (COVID-19) in Wuhan, Hubei province, China on December 11, 2020. (Photo by Aly Song/Reuters)

A woman wearing a mask to help protect against the spread of coronavirus, tries to communicate with Efe, a cat living in Kugulu public garden, in Ankara, Turkey, Monday, November 30, 2020.Turkey's President Recep Tayyip Erdogan has announced Monday the most widespread lockdown so far amid a surge in COVID-19 infections, extending curfews to weeknights and full lockdowns over weekends. (Photo by Burhan Ozbilici/AP Photo)

A performer wears a face shield at a shopping center on New Year's Eve during the coronavirus disease (COVID-19) outbreak, in Bangkok, Thailand on December 31, 2020. (Photo by Soe Zeya Tun/Reuters)