“Kilauea Rules”. The most extreme place we put ours kayakers to paddle till now. Photo location: Big Island, Hawaii. (Photo and caption by Alexandre Socci/National Geographic Photo Contest)

A long exposure image of embers flying off burnt out trees following the wind driven wildfire ranging in the mountain area near Rancho Cucamonga late 30 April 2014. Earlier in the day more than 1,500 homes were evacuated as the Etiwanda fire charred around 1,000 acres in San Barnardino National Forest. (Photo by Stuart Palley/EPA)

A man sits on top of a car as he is stranded on a flooded street in Tianjin, China, July 20, 2016. (Photo by Reuters/Stringer)

A man takes a shower on a street from water coming from a drainpipe as it rains in Havana, Cuba, Wednesday, July 27, 2016. During the last couple of weeks short but intense tropical downpours have been coming down of Havana every afternoon. (Photo by Desmond Boylan/AP Photo)

In this August 1, 2014 photo provided by the National Park Service are male caribou antlers in the Oolah Valley, likely the result of a grizzly kill as he migrated south for the winter at the Arctic National Park and Preserve in Alaska. The nation's northernmost national park says its new management plan will have to consider the effects of a new industrial road to the mining district of Ambler, the first road that would be constructed within its Maryland-sized boundaries. (Photo by Cadence Cook/AP Photo/National Park Service)

Residents walk past an overturned car as the cleanup begins from severe flooding in White Sulphur Springs, W. Va., Friday, June 24, 2016. (Photo by Steve Helber/AP Photo)

Migrants react after boarding the Migrant Offshore Aid Station (MOAS) ship MV Phoenix some 20 miles (32 kilometres) off the coast of Libya, August 3, 2015. Some 118 migrants were rescued from a rubber dinghy off Libya on Monday morning. The Phoenix, manned by personnel from international non-governmental organisations Medecins san Frontiere (MSF) and MOAS, is the first privately funded vessel to operate in the Mediterranean. (Photo by Darrin Zammit Lupi/Reuters)

St Louis County police officers arrest an anti-police demonstrator in Ferguson, Missouri August 10, 2015. Dozens of protesters were arrested on Monday afternoon after blocking rush-hour traffic on Interstate 70 a few miles (km) from Ferguson, Missouri, during demonstrations over the police shooting of an unarmed black man a year ago, according to a Reuters witness. (Photo by Lucas Jackson/Reuters)