Ivanelis Jimenez, front, and Veronica Barreto pose for the camera wearing Puerto Rican flag dresses as they welcome passengers exiting Carnival's Mardi Gras cruise ship, docked in the bay of San Juan, Puerto Rico, Tuesday, August 3, 2021, marking the first time a cruise ship visits the U.S. territory since the COVID-19 pandemic began. (Photo by Carlos Giusti/AP Photo)

Rescuers carry an injured passenger on stretcher at Soshigaya Okura Station after stabbing on a commuter train, in Tokyo Friday night, August 6, 2021. A man with a knife attacked 10 passengers on a commuter train in Tokyo on Friday and was arrested by police after fleeing, fire department officials and news reports said. (Photo by Kyodo News via AP Photo)

Smoke billows from the Mt Etna volcano as seen from Linguaglossa, Sicily on Monday, August 9, 2021. Europe's most active volcano remains active scattering ashes around a vastly populated area on its slopes. (Photo by Marco Restivo/Barcroft Media via Getty Images)

A woman cools off at a fountain in central Cordoba, southern Spain, 11 August 2021. Andalucia was put on orange alert for high temperatures, with a new heatwave forecast to reach temperatures of over 41 degrees Celsius in the region. (Photo by Salas/EPA/EFE)

People wearing face masks to protect against the spread of the coronavirus walk on a crossing in Tokyo Tuesday, August 17, 2021. Japan’s coronavirus state of emergency will continue through Sept. 12 rather than finishing at the end of this month as initially planned, the government decided Monday. (Photo by Koji Sasahara/AP Photo)

A woman rides a donkey during a donkey race in Roum village, Jizeen countryside, southern Lebanon, August 9, 2015. (Photo by Ali Hashisho/Reuters)

Revellers pose during the 24th Street Parade dance music event in Zurich, August 29, 2015. (Photo by Arnd Wiegmann/Reuters)

Indonesian residents look at the Mount Sinabung volcano as it spews volcanic ash near the Tiga Pancur village in Karo, North Sumatra on August 3, 2016. Volcanic eruptions in Indonesia in recent days have forced the closure of two airports and disrupted some flights to the holiday island of Bali, officials said August 3. Mount Sinabung, a volcano on the western island of Sumatra which has been rumbling for some time, also erupted violently on August 2, although its ash clouds did not disrupt any flights. (Photo by Y.T. Haryono/AFP Photo)