Residents make their way along a fence as they try to cross a flooded street after heavy rainfall hit Wuhan, Hubei province, China, July 23, 2015. Severe downpours hit the city on Thursday, flooding streets and shutting down public transportations, local media reported. (Photo by Reuters/China Daily)

Rioters scuffle with police on a street in Mongkok district of Hong Kong, Tuesday, February 9, 2016. Rioters clashed with police overnight and into the early hours of Tuesday in a crowded area of Kowloon. The unrest started when local authorities tried to prevent street food sellers from operating on Monday night. Activists who are dissatisfied with Hong Kong's administration took part in the clashes, local media reports said. (Photo by Kin Cheung/AP Photo)

A Mark IV tank, part of the parade at the Lord Mayor's Show in London. (Photo by Topical Press Agency/Getty Images). November 1917

Members of the French Foreign Legion arriving in Paris for a Bastille Day parade. (Photo by Fox Photos/Getty Images). July 13th 1939

A pug dressed as Yoda from the movie Star Wars walks along the runway at the 9th Annual Pug Parade on February 25, 2006 in Bradenton, Florida. 117 pugs competed for 10 prizes in 6 categories. Proceeds from the event benefit the Sarasota County Humane Society. (Photo by Phillippe Diederich/Getty Images)

Alejandro Simon of Spain prepares to serve during their Preliminary Phase Pool E match against Canada during the VISA FIVB Beach Volleyball International at Horse Guards Parade on August 10, 2011 in London, England. (Photo by Scott Heavey/Getty Images)

A combination picture shows Will Adam, 14, snowboarding down a street on Beacon Hill during a large winter blizzard in Boston, Massachusetts, United States January 27, 2015 (top), and a woman looking at her phone as she walks down the same street June 13, 2015. Outdoor scenes in Boston show local residents enjoying balmy weather amid lush greenery as the summer solstice approaches on 21 June. The very same locations suffered heavy snowstorms last winter, with snow ploughs, skiers and snowboarders battling the drifts. Boston got 275.8 cm of snow over the winter, the most since 1872, when records began. A few months after the snowstorms, Brian Snyder revisited the same places and shot pictures at exactly the same locations. (Photo by Brian Snyder/Reuters)

A truck creates a wake as its driver tries to navigate a severely flooded street as heavy rains pour down Monday, September 8, 2014, in Phoenix. Storms that flooded several Phoenix-area freeways and numerous local streets during the Monday morning commute set an all-time record for rainfall in Phoenix in a single day. (Photo by Ross D. Franklin/AP Photo)