The waning moon sets behind leafless sumac trees on a crisp, clear morning, Thursday, December 15, 2016, in Portland, Maine. Much of the northern Mid-Atlantic and Northeast will stay cold for the next couple of days as the arctic air remains stuck over the northern Appalachians, the National Weather Service said. (Photo by Robert F. Bukaty/AP Photo)

A woman sits behind a bicycle on a cold winter morning in New Delhi, December 31, 2019. (Photo by Anushree Fadnavis/Reuters)

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)

A tourist stands on a paddle boat near soldiers taking part on a military and police drill in preparation for the temporary closure of the holiday island Boracay in Philippines on April 24, 2018. (Photo by Erik De Castro/Reuters)

Second place, Nature: double trapping. Picture taken in the Brazilian Pantanal ... when I downloaded the CF did not want to believe it ... The nature knows we always give magnificent events but sometimes extraordinary. (Photo by Massimiliano Bencivenni/National Geographic Travel Photographer of the Year Contest)

A pupil arrives on the first day of school at Yas American Academy in Abu Dhabi in the last decade of August 2025. (Photo by Victor Besa/The National)

Agriculture Secretary Sonny Perdue adjusts his mask before an event in the Roosevelt Room of the White House, Tuesday, May 19, 2020, in Washington. (Photo by Evan Vucci/AP Photo)

People stroll alongside one of the hills of the Tio Pio park in Madrid, Monday, January 25, 2016. The park is a high viewpoint frequented mostly by locals due to its view of the Spanish capital skyline. (Photo by Francisco Seco/AP Photo)