Students stand on the roof of a wooden boat as haze blankets the Musi River while they travel to school in Palembang, on Indonesia's Sumatra island, September 10, 2015. Indonesia is investigating 10 firms over worsening forest fires that have created a blanket of smog over Southeast Asia, threatening them with sanctions if they are found responsible, a government minister said on Tuesday. The thick haze from Indonesia's Sumatra and Kalimantan islands has forced the repeated cancellation of flights in the area and pushed air quality to unhealthy levels in neighbouring Singapore and Malaysia. (Photo by Reuters/Beawiharta)

Four-year-old Solaris Arias (right) jumps through water spraying from an open fire hydrant in Providence, Rhode Island, on June 20, 2012. Much of the state remained under a heat advisory Tuesday afternoon because of the steamy air mass that has moved into the region resulting in temperatures in the 90s. (Photo by Steven Senne/AP Photo)

A round circle of smoke coming from the mouth of the Etna volcano is seen in the sky during an eruption on the southern Italian island of Sicily April 11, 2013. Mount Etna is Europe's tallest and most active volcano. (Photo by Antonio Parrinello/Reuters)

Seehund “Bruno” looks out of his transport box before making his way to the water on the beach of the island of Juist, Germany on August 14, 2013. Four young seals were released after six weeks of recovery at a rescue station in Norden-Norddeich. (Photo by Carmen Jaspersen/AFP Photo/DPA)

Playful seals. The pair of playful seals swim around each other. Two passionate seals were captured on camera in a tender embrace by underwater photographer Robert Bailey, 50, near the Farne Islands off the Northumberland coast, UK. (Photo by Robert Bailey/Medavia)

Tsukimi Ayano steps out of her house in the village of Nagoro on Shikoku Island in southern Japan February 24, 2015. Tsukimi Ayano made her first scarecrow 13 years ago to frighten off birds pecking at seeds in her garden. The life-sized straw doll resembled her father, so she made more. Today, the tiny village of Nagoro in southern Japan is teeming with Ayano's hand-sewn creations, frozen in time for a tableau that captures the motions of everyday life. (Photo by Thomas Peter/Reuters)

Garrett Gerloff (L) of the USA GRT Yamaha WorldSBK Junior Team and Sandro Cortese (R) of Germany on OUTDO Kawasaki TPR colide during a warm up session of the the World Superbike Championship on Phillip Island, Victoria, Australia, 01 March 2020. (Photo by Scott Barbour/EPA/EFE)

In this picture taken Thursday, August 4, 2016, seal Tristan looks out of a basket while being released into the North Sea together with others at the beach of the island Juist, Germany. He is part of the first group of released seals of the seal breeding station Norddeich this year. (Photo by Carmen Jaspersen/DPA via AP Photo)