People are seen in the crowd as Serbian Emir Kusturica & The No Smoking Orchestra performs during the third day of the Mexican musicial festival Vive Latino, at the Foro Sol in Mexico City, on March 29, 2014. (Photo by Alfredo Estrella/AFP Photo)

“Just hanging out”. As full autumn hits the valley of Hallingdal in Norway, this bear chills out in a tree which seems to barely cover its weight. Photo location: Flå, Hallingdal, Norway. (Photo and caption by Jorgen Tharaldsen/National Geographic Photo Contest)

This picture taken on July 25, 2014 shows people cooling off in a waterpark in Suining, southwest China's Sichuan province. Meteorological departments issued an orange alert for high temperature as a heat wave embraces Sichuan province, with temperature of most area topped 37, local media reported. (Photo by AFP Photo)

Members of the Baby Dolls, a traditional Mardi Gras social club, dance during a second line parade honoring music legend Fats Domino, in New Orleans, Wednesday, November 1, 2017. The thousand-strong group marched and danced from Vaughn's Lounge to Domino's former home in the Lower 9th Ward. Domino, a New Orleans native, died this past week. (Photo by Gerald Herbert/AP Photo)

A spectator cools herself at a water spraying fan at the Australian Open tennis championships in Melbourne, Australia, Tuesday, January 17, 2017. (Photo by Kin Cheung/AP Photo)

Revellers ride during the 54th annual brass band festival in the Serbian village of Guca August 7, 2014. Every year Guca is swamped by thousands of people taking part in the celebration of brass band music. (Photo by Marko Djurica/Reuters)

A folk performer (front R) with make-up and props takes part in a “Blood Shehuo” parade, during a performance in Linyi county, Shanxi province March 21, 2015. “Shehuo” is the common name of Chinese traditional activities consisting of folk performances in northern China. The “Blood Shehuo” performers use make-up and props to re-enact scenes of horror in classic Chinese novels like Water Margin. (Photo by Reuters/Stringer)

A South Sudanese People Liberation Army (SPLA) soldier patrols the streets in Malakal on January 21, 2014. (Photo by Harrison Ngethi/AFP Photo)