Julian, left, is photographed by his mother with friend Gianluca, right, under water at a public pool in Gelsenkirchen, Germany, on a hot Friday, July 3, 2015. Germany faces a heat wave with temperatures up to 38 degrees Celsius (100 degrees Fahrenheit) at the weekend. (Photo by Martin Meissner/AP Photo)

A Fulton Hotshot lights a controlled burn on the so-called “Rough Fire” in the Sequoia National Forest, California, August 21, 2015. In California, suffering its worst drought on record, about 2,500 people were forced to flee Christian camps east of Fresno at Hume Lake as the so-called Rough Fire crossed Highway 180, officials said. (Photo by Max Whittaker/Reuters)

US freestyler, gold medalist Mcrae Williams competes during the men' s SlopeStyle (SS) finals at the FIS Snowboard and Freestyle Ski World Championships 2017 in Sierra Nevada on March 19, 2017. (Photo by Albert Gea/Reuters)

A boy holds his mother's leg as he cries in front of their damaged house after a strong 6.6 magnitude earthquake at Longmen village, Lushan county in Ya'an, Sichuan province. (Photo by Jason Lee/Reuters)

Sri Lankan military personnel march during the country's 66th Independence Day celebrations in the central town of Kegalle, about 40 kms from the capital Colombo on February 4, 2014. Sri Lanka cemmemorates its independence from British rule on February 4, 1948. (Photo by Ishara S. Kodikara/AFP Photo)

A visitor holds an Israeli-made rifle during the 8th International Land and Naval Defense system exhibition, in New Delhi, India, on February 6, 2014. (Photo by Anindito Mukherjee/Reuters)

A newborn baby giraffe shows its tongue at the Planckendael zoo in Mechelen, 25 kilometers North of Brussels, Tuesday, February 18, 2014. The calf was born on Valentines day, February 14, and has a heart shaped spot on the hip. (Photo by Yves Logghe/AP Photo)

A man watches the approaching flames as the Springs fire continues to grow near Camarillo, California, on May 3, 2013. The wildfire has spread to more than 18,000 acres on day two and is 20 percent contained. (Photo by David McNew)