U.S. Secretary of State John Kerry stands inside the historic Shackleton hut near McMurdo Station, Antarctica, Friday, November 11, 2016. Kerry became the highest-ranking American official to visit Antarctica when he landed for a two-day trip on Friday. He's been hearing from scientists about the impact of climate change on the frozen continent. Kerry's aides described the trip as a learning opportunity for the secretary of state. He has been receiving briefings from scientists working to understand the effects of climate change on Antarctica. Kerry has made climate change an intensive focus of American diplomacy during his term, and had previously spent decades working on the issue as a U.S. senator. Trump has called climate change a hoax and said he would “cancel” U.S. involvement in the landmark Paris Agreement on global warming. (Photo by Mark Ralston/Pool Photo via AP Photo)

Barrier tape is tied around 15-month-old Shivani's ankle to prevent her from running away, while her mother Sarta Kalara works at a construction site nearby, in Ahmedabad, India, April 19, 2016. Kalara says she has no option but to tether her daughter Shivani to a stone despite her crying, while she and her husband work for 250 rupees ($3.8) each a shift digging holes for electricity cables in the city of Ahmedabad. There are about 40 million construction workers in India, at least one in five of them women, and the majority poor migrants who shift from site to site, building infrastructure for India's booming cities. Across the country it is not uncommon to see young children rolling in the sand and mud as their parents carry bricks or dig for new roads or luxury houses. (Photo by Amit Dave/Reuters)

A man works on a small replica of the Iron Man armor next to a homemade replica of the “Hulkbuster” Iron Man armour from the movie “Avengers: Age of Ultron”, at an underground parking lot in Zhengzhou, Henan province, China, May 12, 2015. The 3.4-metre-tall replica is made of over 100 fiber-reinforced plastic components. It took Xing and his friends two months to put them together after watching the trailer of the movie in March, local media reported. (Photo by Reuters/Stringer)

Medical staff celebrate after all patients were discharged at a temporary hospital set up to treat people with the COVID-19 coronavirus in Wuhan in China's central Hubei province on March 9, 2020. China closed most of its makeshift hospitals for coronavirus patients, some schools reopened and Disney resort staff went back to work on March 9 as normality slowly returns to the country after weeks battling the epidemic. (Photo by AFP Photo/China Stringer Network)

In this March 30, 2020, photo, Zandile Mlotshwa, 21, cashier at Spar supermarket in the Norwood suburb of Johannesburg, counts her cash at the end of her shift. From South Africa to Italy to the U.S., grocery workers – many in low-wage jobs – are manning the front lines amid worldwide lockdowns, their work deemed essential to keep food and critical goods flowing. (Photo by Jerome Delay/AP Photo)

This picture taken on May 4, 2020 shows gentoo penguins chasing krill during feeding time in their enclosure at the Ocean Park theme park, which is currently closed due to the COVID-19 novel coronavirus, in Hong Kong. Save for an absence of gawping crowds, life for the penguins of Hong Kong's Ocean Park has been much the same during the coronavirus pandemic – but their carers have worked long shifts to keep the monochrome troupe healthy. (Photo by Anthony Wallace/AFP Photo)

Camila Hormazabal, a 24-year-old sеx worker, uses a laptop to connect to the web and keep an online erotic meeting with a virtual customer in Concepcion, Chile on April 7, 2020. Hormazabal reinvented herself offering sexual services online after the nightclub where she had worked was closed due to the outbreak of the coronavirus disease (COVID-19). (Photo by Juan Gonzalez/Reuters)