Villagers look on as Mount Sinabung volcano spews thick volcanic ash, as seen from Beganding village in Karo, North Sumatra province, on May 19, 2017. Sinabung roared back to life in 2010 for the first time in 400 years. After another period of inactivity, it erupted once more in 2013 and has remained highly active since. (Photo by Ivan Damanik/AFP Photo)

Visitors watch as Grigory Broverman, a member of the Cryophile winter swimmers club, pours a bucket of cold water over his 6-year-old daughter Liza during a flash mob, part of a celebration of Polar Bear Day at the Royev Ruchey Zoo in a suburb of the Siberian city of Krasnoyarsk, Russia, November 29, 2015. The air temperature was around minus 5 degrees Celsius. (Photo by Ilya Naymushin/Reuters)

In this January 7, 2016, photo, conservationists of Borneo Orangutan Survival Foundation hold a baby orangutan rescued along with its mother during a rescue and release operation for orangutans trapped in a swath of jungle in Sungai Mangkutub, Central Kalimantan, Indonesia. Last year's forest fires drove orangutans closer to the river bank, where they had to live in an over-populated swath of forest as thin as 30 meters wide along the river. (Photo by Dita Alangkara/AP Photo)

An Iranian man sells colorful ropes at the Tehrans old Bazaar, the place where the main economy trades take place, in Tehran, Iran, 25 January 2016. Reports state that Iranian officials expected the Iranian economy to grow on an average of eight percent over the coming five years following the lifting of sanctions against Iran. (Photo by Abedin Taherkenareh/EPA)

Pictures from Tasmania’s central plateau, shot by wilderness photographer Dan Broun, show the extraordinary damage wrought by more than a week of bushfires following lightning strikes in Australia’s southernmost state on January 13. 2016. The world heritage area was home to a range of unique alpine flora including pencil pines, king billy pines and cushion plants, some more than 1,000 years old. Now more than 10,000ha of land has been incinerated, and ecologist say that, unlike eucalyptus trees, the ancient flora will not recover. (Photo by Dan Broun)

Residents watch volcanic smoking and ashes rising from Mount Sinabung during an eruption in Karo, North Sumatra, Indonesia, February 24, 2016. Authorities have repeatedly called on local residents to remain patient in dealing with the impact of Sinabung's eruptions, which some experts have predicted will continue for five more years. (Photo by Xinhua/Barcroft Media)

Balinese Hindus carry Pratimas, or symbols of God, on the beach during Melasti, a purification ceremony, ahead of the holy day of Nyepi, in Gianyar on the Indonesian resort island of Bali, March 6, 2016. Nyepi is a day of silence to celebrate the Balinese new year, reserved for self-reflection, where people are not allowed to use lights, light fires, work, travel or enjoy entertainment. (Photo by Roni Bintang/Reuters)

In this Monday, March 28, 2016 photo, trainer Catrina Bloomquist works with Nav, an 11-year-old rescued California sea lion, as part of a new exhibit opening at the Georgia Aquarium. The aquarium is in the midst of celebrating its tenth anniversary, and as part of the festivities, patrons will be introduced to the newest faces in Atlanta, a group of rescued California sea lions. (Photo by David Goldman/AP Photo)