Members of security forces secure Tahrir Square in Cairo, Egypt, November 11, 2016. Egypt imposed a big security clampdown in its cities on Friday as mass demonstrations called to protest against austerity measures failed to take place. Riot police and armored vehicles filled the otherwise empty streets of central Cairo, but most people stayed at home. (Photo by Mohamed Abd El Ghany/Reuters)

Rachel Miner, 15, left, of Emmetsburg, Iowa, sits with Carlotta Haas, 15, a foreign exchange student from Duesseldorf, Germany, who had been living with Miner and her family but was called home, as they waited for her flight Wednesday, March 25, 2020, in at Minneapolis-St. Paul International Airport in Minneapolis. (Photo by Anthony Souffle/Star Tribune via AP Photo)

Armed homeowners standing in front their house on Portland Place and confront protesters marching to St. Louis Mayor Lyda Krewson's house in Missouri, U.S. on June 28, 2020. The protesters called for Krewson's resignation for releasing the names and addresses of residents who suggested defunding the police department. (Photo by Laurie Skrivan/St. Louis Post)

A member of the riot police gets ready to repel the attacks of protesters during a protest against President Sebastian Piñera during the seventh day of protests against President Sebastian Piñera on October 24, 2019 in Santiago, Chile. Although President Sebastian Piñera announced measures to improve equality, unions called for a national strike and demonstrations continue as casualties are now at least 18. Demands behind the protest include issues like health care, pension system, privatization of water, public transport, education, social mobility and corruption. (Photo by Marcelo Hernandez/Getty Images)

A woman tries to cross a flooded street as people walk on a trestle bridge during high water, in Venice, northern Italy, Friday, November 15, 2019. Exceptionally high tidal waters returned to Venice on Friday, prompting the mayor to close the iconic St. Mark’s Square and call for donations to repair the Italian lagoon city just three days after it experienced its worst flooding in 50 years. (Photo by Andrea Merola/ANSA via AP Photo)

Palestinians scuffle with Israeli forces at Damascus Gate in Jerusalem's Old City on December 8, 2017. Palestinians clashed with Israeli security forces after calls for a “day of rage” as US President Donald Trump's declaration of Jerusalem as Israel's capital sent shockwaves through the region for a second day. (Photo by Thomas Coex/AFP Photo)

People stand near beached sperm whales on January 13, 2016, after they became stranded on the Dutch island of Texel the day before. Five sperm whales which became stranded on Texel have died, officials said January 13. Experts said the beached whales had already been badly injured and their chances of survival were poor. Volunteers tried to save them but called off their efforts late in the night because of bad weather and darkness, ANP news agency said. (Photo by Remko de Waal/AFP Photo/ANP)

This undated photo provided by NOAA in May 2018 shows aurora australis near the South Pole Atmospheric Research Observatory in Antarctica. When a hole in the ozone formed over Antarctica, countries around the world in 1987 agreed to phase out several types of ozone-depleting chemicals called chlorofluorocarbons (CFCs). Production was banned, emissions fell and the hole shriveled. But according to a study released on Wednesday, May 16, 2018, scientists say since 2013, there’s more of a banned CFC going into the atmosphere. (Photo by Patrick Cullis/NOAA via AP Photo)