A protester gestures during a “Yellow vest” protest against higher fuel prices during clashes on the Champs-Elysees in Paris, France, November 24, 2018. (Photo by Benoit Tessier/Reuters)

A sandstorm hits the city of Zhangye in Gansu province, China on November 27, 2018. (Photo by Reuters/China Stringer Network)

A military cadet gets help from a colleague to adjust her hair before taking part the military parade in Bucharest, Romania, Saturday, December 1, 2018, as thousands turned out Saturday to celebrate 100-years since Romania became a modern-day state, amid concerns about rule of law and the state of democracy. Crowds braved temperatures of minus 5 Celsius (23 Fahrenheit) to watch the military parade of troops, tanks and military vehicles. (Photo by Vadim Ghirda/AP Photo)

An emotional former President George Bush, sniffs after touching the flag-draped casket of his father, former President George H.W. Bush, during his State Funeral at the National Cathedral, Wednesday, December 5, 2018, in Washington. (Photo by Andrew Harnik/Pool via Reuters)

A reveler performs during the Myths and Legends parade in Medellin, Antioquia department, Colombia on December 8, 2018. (Photo by Joaquín Sarmiento/AFP Photo)

Armed women attend a rally to show support to the Houthi movement in Sanaa, Yemen January 13, 2018. (Photo by Khaled Abdullah/Reuters)

In this photo taken on Sunday, January 14, 2018, Anastasia Gruzdeva, left, poses for selfie with her friends as the temperature dropped to about –50 degrees (–58 degrees Fahrenheit) in Yakutsk, Russia. Temperatures in the remote, diamond-rich Russian region of Yakutia have dropped to near-record lows, plunging to –67 degrees Centigrade (-88.6 degrees Fahrenheit) in some areas. (Photo by Sakhalife.ru Photo via AP Photo)

David Goffin of Belgium meets a koala during a promotional event for the Australian Open tennis tournament at Melbourne Park on January 17, 2018. (Photo by Fiona Hamilton/Reuters/Tennis Australia)