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)

Girls of the Long Horn Miao ethnic minority group wear headdresses as they prepare gather for Tiaohua or Flower Festival as part of the Lunar New Year on February 6, 2017 in Longga village, Guizhou province, southern China. (Photo by Kevin Frayer/Getty Images)

Climate change activist Greta Thunberg reacts during a news conference during COP25 climate summit in Madrid, Spain, December 9, 2019. (Photo by Juan Medina/Reuters)

Demonstrators perform a dance in front of riot policemen during a march called by students to request changes in the education system in Santiago, Chile September 5, 2017. (Photo by Ivan Alvarado/Reuters)

A protester reacts as police use water cannon during a demonstration to demand changes in the Chilean education system in Santiago, Chile June 25, 2015. (Photo by Ueslei Marcelino/Reuters)

Ocean Rebellion put on a display of puking oil heads ahead of climate change conference COP26 in Glasgow, Britain, 29 October 2021. (Photo by Robert Perry/EPA/EFE)

Climate change activists dressed up as black birds protest in St. Ives, on the sidelines of the G7 summit in Cornwall, Britain, June 11, 2021. (Photo by Dylan Martinez/Reuters)

A robin perches on a spade handle in a garden on a rainy day in Lixwm, north Wales. Researchers said this week that when European robins are subjected to human-produced noise, their behaviour changes. (Photo by DGDImages/Alamy Live News)