Lightning illuminates a thundercloud as a storm front hits the North Sea region near Westerhever, northern Germany, on August 11, 2014. (Photo by Daniel Reinhardt/AFP Photo/DPA)

Gold medallists of China perform Synchronised Swimming Free Combination routine at the Munhak Park Tae-hwan Aquatics Center during the 17th Asian Games in Incheon September 23, 2014. (Photo by Tim Wimborne/Reuters)

This long exposure picture shows vehicles on roads during rush hour on the eve of the National Day holidays in Shanghai on September 30, 2014. According to local media, police checkpoints will be set up at highways, elevated roads and business hubs to tackle drunk driving during the National Day holiday. (Photo by Johannes Eisele/AFP Photo)

A woman waters the plants outside her house in an alley at a slum in Mumbai October 28, 2014. (Photo by Danish Siddiqui/Reuters)

A girl who suffers from hearing and speech disorders reacts to the camera at a rehabilitation centre supported by Bhopal Medical Appeal, for children who were born with mental and physical disabilities, in Bhopal November 11, 2014. The rehabilitation centre only treats families they believe have been affected by the Union Carbide gas leak 30 years ago. Human rights groups say that thousands of tonnes of hazardous waste remain buried underground, and the government has conceded it is contaminated. There has, however, been no long-term epidemiological research which conclusively proves that birth defects are directly related to the drinking of the contaminated water. (Photo by Danish Siddiqui/Reuters)

Gloria Lincoln-Thompson carries her 9mm Smith & Wesson pistol in her waistband during a rally in support of the Michigan Open Carry gun law in Romulus, Michigan, in this April 27, 2014 file photo. (Photo by Rebecca Cook/Reuters)

A jogger runs on the bank of Donaukanal channel in central Vienna, Austria, September 5, 2016. (Photo by Heinz-Peter Bader/Reuters)

The moon rises behind the skyline and financial district in Toronto, November 25, 2015. (Photo by Mark Blinch/Reuters)