In this Thursday, December 1, 2016 photo, Cat Bigney, part of the Oglala Native American tribe, waits on the shore of the Cannonball river for travelers to arrive by canoe at the Oceti Sakowin camp where people have gathered to protest the Dakota Access oil pipeline in Cannon Ball, N.D. So far, those at the camp have shrugged off the heavy snow, icy winds and frigid temperatures. But if they defy next week's government deadline to abandon the camp, demonstrators know the real deep freeze lies ahead. Life-threatening wind chills and towering snow drifts could mean the greatest challenge is simple survival. (Photo by David Goldman/AP Photo)

The Northern Lights glow green in a spectacular light show above a field of trees frozen solid with snow. (Photo by Jaak Sarv/Solent News & Photo Agency)

A woman rides a donkey during a donkey race in Roum village, Jizeen countryside, southern Lebanon, August 9, 2015. (Photo by Ali Hashisho/Reuters)

In this July 9, 2016 file photo, girls jump from a diving platform into the Geneva Lake and enjoy sunny and warm weather, in Villeneuve, Switzerland. After nearly 90 years, women can legally swim topless in Geneva’s lake and Rhone River without running the risk of a fine. Geneva’s regional council has voted to modify a 1929 ordinance that banned women from swimming topless in the city’s main natural waterways, though the change doesn’t apply to public swimming pools or swimming totally naked. Nicolas Bolle, an official with Geneva’s security department, on Thursday, April 6, 2017 confirmed the council’s action a day earlier. (Photo by Jean-Christophe Bott/Keystone via AP Photo)

Pakistani students look out from a vehicle on their way to school near the Army Public School which was targeted by Taliban militants last year, in Peshawar, Pakistan, Monday, January 12, 2015. (Photo by B.K. Bangash/AP Photo)

An Afghan man prepares tea for customers at a roadside tea shop on the outskirts of Jalalabad February 2, 2015. (Photo by Reuters/Parwiz)

A P-51 Mustang named “Charlotte's Chariot” from the Southern Heritage Air Foundation flies past a cloud of smoke and fire from a nearby battle reenactment during the Wings Over Houston Airshow in Houston, on Saturday, November 1, 2014. Battle reenactments are part of the yearly show held at Ellington Airport. (Photo by Kar Hlava/AP Photo/Bay Area Citizen)

Actor Bella Thorne (L) and model Amber Rose at the NYLON Young Hollywood Party at AVENUE Los Angeles on May 2, 2017 in Los Angeles, California. (Photo by Joe Scarnici/Getty Images for NYLON)