Rwandan refugees cross the Rusumo border to Tanzania from Rwanda carrying their belongings, goats, mattresses and cows, May 30, 1994. The bloodshed that claimed 800,000 Tutsi and moderate Hutu lives began 25 years ago on April 7, 1994, when a plane carrying Rwandan President Juvenal Habyarimana, Burundi President Cyprien Ntaryamira and a French air crew was shot down. (Photo by Jeremiah Kamau/Reuters)

Arizona Cardinals cheerleader Claire Thorton, center, smiles as Air Force Capt. Eric Straub proposes to her during the first half of an NFL football game against the Washington Redskins, Sunday, October 12, 2014, in Glendale, Ariz. Thorton accepted the proposal. (Photo by Rick Scuteri/AP Photo)

King Abdullah of Jordan and Queen Rania who holds Princess Salma in her arms, pose for a portrait November 20, 2000 in Amman, Jordan

Winner of the National Park Foundation's photo contest; Honorable Mention: Fan Favorite. Grand Canyon National Park, Arizona. Three friends enjoy sunrise over the Grand Canyon. (Photo by Peter Blanchard)

Lighting from an approaching thunder storm strikes near the shore in Panama City Beach, Fla., on Thursday, July 10, 2014. (Photo by Brennen Smith/AP Photo/The Decatur Daily)

Brian Skerry can be called many things – explorer, journalist, conservation advocate – but he is first and foremost a photographer. His journeys to capture amazing underwater photographs have taken him across the world’s oceans. Photo: This Bahamian oceanic whitetip shark, known for the distinctive coloring on its white-tipped, rounded extremities, is part of a globally threatened species due to overfishing demands, primarily for its fins. (Photo by Brian Skerry)

Dave Zdanowicz, a prominent landscape photographer from the north of England, here shares his favourite shots from this year. This series brings together photos from January to last month, displaying the fine range of English seasons he has documented. Here: Misty sunrise at Winnat's Pass, Derbyshire on August 26, 2016. (Photo by Dave Zdanowicz/Rex Features/Shutterstock)

A surfer braves a large wave at Queenscliff in Sydney, Monday, June 6, 2016. Storms have lashed Australia's easter coast for several days whipping up waves as high as 12 meters (40 feet), which caused serious beach erosion and forced hundreds of coastal residents to evacuate. (Photo by Rick Rycroft/AP Photo)