This combination of August 30, 2005 and July 29, 2015 aerial photos shows downtown New Orleans and the Superdome flooded by Hurricane Katrina and the same area a decade later. Katrina's powerful winds and driving rain bore down on Louisiana on August 29, 2005. The storm caused major damage to the Gulf Coast from Texas to central Florida while powering a storm surge that breached the system of levees that were built to protect New Orleans from flooding. (Photo by David J. Phillip/Gerald Herbert/AP Photo)

A male deer barks at dawn during the annual deer rutting season at Richmond Park in London, Britain, October 9, 2016. (Photo by Toby Melville/Reuters)

Comandos de Salvamento rescuers Maria Martinez (L) and Ana Chichilla attend to a wounded homeless man in San Salvador, El Salvador July 16, 2016. The man was attacked with a machete by suspected gang members. In 2015, El Salvador registered a record 103 homicides per 100,000 habitants, making it one of the most dangerous countries in the world outside a war zone. But for many young people who have few chances to distance themselves from rivalries between so-called maras in their schools and neighbourhoods, a civil-society organisation called the Comandos de Salvamento, or Rescue Corps, has been a refuge. (Photo by Jose Cabezas/Reuters)

A woman smokes a cigar as she reads the newspaper in a street of Havana, on November 26, 2016, the day after Cuban revolutionary leader Fidel Castro died aged 90. One of the world's longest-serving rulers and modern history's most singular characters, Castro defied 11 US administrations and hundreds of assassination attempts. (Photo by Yamil Lage/AFP Photo)

A woman worker prepares her stall at Tanah Abang textile market in Jakarta, Indonesia January 11, 2017. (Photo by Fatima El-Kareem/Reuters)

The battleship USS Iowa fires its 16-inch guns during duty in the Persian Gulf on December 16, 1987. In 1943, the Iowa ferried President Franklin Roosevelt home from the Teheran Conference, where post-WW II leaders divided up the world. The ship fought battles from the South Pacific to Korea and escorted convoys through the Persian Gulf. Forty-seven sailors died atop its deck when an explosion ripped through a gun turret. Now, the new port for the retired USS Iowa just might be the home of California's annual asparagus festival, the gritty agriculture port town of Stockton on the San Joaquin River, about 80 miles inland from San Francisco. (Photo by Eric Risberg/AP Photo)

Police officers display their AI-powered smart glasses in Luoyang, Henan province, China on April 4, 2018. (Photo by Reuters/China Stringer Network)

In this Thursday, June 14, 2018, file photo, students wear virtual reality goggles during a science class at Pyongyang Teachers' University, a teacher training college, in Pyongyang, North Korea. (Photo by Dita Alangkara/AP Photo)