Clouds gather as walkers pause atop a ridge in Mountain View, California January 7, 2016. (Photo by Noah Berger/Reuters)

A pro-independence protester sits in front of Catalonia's regional parliament as lawmakers vote inside, in Barcelona, January 16, 2014. (Photo by Albert Gea/Reuters)

Saudi youths demonstrate a stunt known as “sidewall skiing” (driving on two wheels) in the northern city of Tabuk, in Saudi Arabia December 3, 2014. (Photo by Mohamed Al Hwaity/Reuters)

A visitor stands in the exhibition “I Am A Drop In The Ocean” dedicated to the artistic and visual expressions of the protests that shook the Ukraine from November 2013 until February 2014 at the Kuenstlerhaus gallery in Vienna, Austria, Thursday, April 10, 2014. The exhibition opens its doors from April 11 until May 23, 2014. (Photo by Ronald Zak/AP Photo)

With the United Nations and Tudor City in the foreground, lightning strikes in the sky over the East River as a major storm approaches New York City July 2, 2014. Tropical Storm Arthur, the first of the Atlantic hurricane season, gathered strength July 20, 2014 and would likely reach hurricane strength over the next couple of days. (Photo by Timothy A. Clary/AFP Photo)

An Iraqi man cooks traditional Masgouf fish on a barbecue for sale in the Karada market July 02, 2014. Masgouf, one of the national dishes of Iraq is a grilled carp seasoned with olive oil, rock salt, tamarind and ground turmeric. (Photo by Scott Nelson for the Washington Post)

Members of a teenage girl gang convincing an unwilling recruit to join the gang, circa 1955. (Photo by Vecchio/Three Lions)