U.S. President Barack Obama laughs as he reads the storybook “Where the Wild Things Are” during the annual Easter Egg Roll at the White House in Washington April 6, 2015. Thousands of children gathered at the White House for the annual Easter Egg Roll. This year's event features live music, cooking stations, storytelling, and of course, some Easter egg roll. (Photo by Jonathan Ernst/Reuters)

Revellers use water guns as they participate in a water fight during Songkran Festival celebrations at Kowloon City district, known as Little Thailand as there is large number of restaurants and shops run by Thais, in Hong Kong April 12, 2015. The Songkran festival, also known as the water festival, marks the start of Thailand's traditional New Year and is believed to wash away bad luck. (Photo by Tyrone Siu/Reuters)

Bridegrooms pose for a photograph as they attend a mass wedding ceremony at Arena Corinthians soccer stadium in Sao Paulo, Brazil, September 26, 2015. According to the event's organizers, at least 400 couples tied the knot during a mass wedding which was organized by the Department of Justice and Citizenship of the state of Sao Paulo. (Photo by Paulo Whitaker/Reuters)

A reporter takes pictures of a soldier during the annual Han Kuang military exercise in Kinmen, Taiwan, September 7, 2015. Rustic Kinmen, with a population of less than 129,000, is a half-hour ferry ride to China, but it takes an hour to fly to major Taiwan cities. Just off its shores, glass-walled high-rises wink seductively from the booming mainland port of Xiamen in one of China's most prosperous provinces. (Photo by Pichi Chuang/Reuters)

The Aletsch Glacier is pictured at dusk in Fiesch, Switzerland, August 11, 2015. One of Europe's biggest glaciers, the Great Aletsch coils 23 km (14 miles) through the Swiss Alps – and yet this mighty river of ice could almost vanish in the lifetimes of people born today because of climate change. The glacier, 900 metres (2,950 feet) thick at one point, has retreated about 3 km (1.9 miles) since 1870 and that pace is quickening. (Photo by Denis Balibouse/Reuters)

A hyena eyes a herd of zebra at Lake Nakuru National Park, Kenya, August 19, 2015. The Park is home to some of the world's most majestic wildlife including lions, rhinos, zebras and flamingos. The scenery is stunning, from forests of acacia trees to animals congregating at the shores to drink. UNESCO says that with rapid population growth nearby, the area is under "considerable threat from surrounding pressures," particularly deforestation, a contributing factor in floods. (Photo by Joe Penney/Reuters)

A worker looks on with his camel as he waits for tourists at the Giza Pyramids on the outskirts of Cairo, Egypt, November 8, 2015. Egypt's Tourism Minister Hesham Zaazou said Cairo regretted the suspension of flights and was doing all it could to secure its airports and tourist sites, adding that he would fly to Sharm al-Sheikh to oversee measures to support tourists there. (Photo by Amr Abdallah Dalsh/Reuters)

A model wears a bazin dress made by designer Fadi Maiga in Bamako, Mali, October 21, 2015. Gasps of delight filled the convention hall as models, decked out in Mali's signature bazin fabric in crimson reds, indigoes and neon greens, strutted the catwalk while musicians from across the West African nation provided the soundtrack. (Photo by Joe Penney/Reuters)