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)

Colorado Gov. John Hickenlooper shows off his socks--one with Democratic presidential candidate Bernie Sanders and the other with Republican candidate Donald Trump – before entering his former brewpub for a book signing event to mark the release of his autobiography Thursday, May 26, 2016, in Denver. Hickenlooper, who is term-limited, is doing book talk rounds this week, reviving speculation that he is positioning himself to join Hillary Clinton's presidential campaign ticket. (Photo by David Zalubowski/AP Photo)

Attendees visit the Ford booth during Auto China 2018 show held in Beijing, China, Wednesday, April 25, 2018. Auto China 2018, the industry's biggest sales event this year, is overshadowed by mounting trade tensions between Beijing and U.S. President Donald Trump, who has threatened to hike tariffs on Chinese goods including automobiles in a dispute over technology policy. (Photo by Ng Han Guan/AP Photo)

A Hezbollah supporter fires a rocket-propelled grenade in the air to celebrate the arrival of Iranian fuel tankers to Lebanon, in the eastern town of Baalbek, Lebanon, Thursday, September 16, 2021. The delivery violates US sanctions imposed on Tehran after former President Donald Trump pulled America out of a nuclear deal between Iran and world powers three years ago. (Photo by Bilal Hussein/AP Photo)

A woman at Foyles bookshop looks at a copy of J. K. Rowling's latest novel “The Casual Vacancy” which has gone on sale today starting at 8:00 am on September 27, 2012 in London, England. “The Casual Vacancy” is J. K. Rowling's first book aimed at an adult readership and is centered on a parish council election in a small West Country town. (Photo by Oli Scarf)

A voter wearing protective face mask shows off her finger marked with ink indicating she voted as she leaves a polling station Sunday, November 8, 2020, in Yangon, Myanmar. Voting was underway in Myanmar’s elections on Sunday, with the party of Nobel Peace Prize laureate Aung San Suu Kyi heavily favored to retain power it had wrestled from the powerful military five years ago. (Photo by Thein Zaw/AP Photo)

Soldiers from the Nigerian Armed Forces take position and secure the streets in Lagos Island, Lagos, on February 27, 2023, after hoodlums had harassed market owners. Nigeria slowly counted more results on Monday after a tight election for the presidency of Africa's most populous nation as delays and accusations of manipulation fuelled tensions Nearly 90 million were eligible to vote on Saturday for a successor to President Muhammadu Buhari, with many hoping for a new leader to tackle insecurity, economic malaise and widening poverty. (Photo by John Wessels/AFP Photo)

In this Saturday, June 14, 2014 file photo, two women kiss in front of a rainbow flag, the symbol of the gay rights movement, during the Gay Pride parade in central Athens, Greece. Ahead of May 21, general elections, Alexis Tsipras, head of the main left-wing opposition party, Syriza, promised on Tuesday, April 4, 2023 to legalize same-s*x marriage if he becomes the next prime minister. (Photo by Petros Giannakouris/AP Photo)