In this Friday, December 4, 2018 photo, a half sunken cruise ship lays on its side, in the Gulf of Elefsina, west of Athens. Dozens of abandoned cargo and passenger ships lie semi-submerged or completely sunken around the Gulf of Elefsina, near Greece’s major port of Piraeus. Now authorities are beginning to remove the dilapidated ships. Some of them have been there for decades, leaking hazards like oil into the environment and creating a danger to modern shipping. One expert calls the abandoned ships “an environmental bomb”. (Photo by Thanassis Stavrakis/AP Photo)

An Indian sadhu (Hindu holy man) sits on the banks of Sangam – the confluence of the Ganges, Yamuna and mythical Saraswati rivers – on the auspicious bathing day of 'Maghi Purnima' during the Kumbh Mela festival in Allahabad on February 19, 2019. Millions of Hindu pilgrims took the plunge in holy rivers on the most auspicious bathing days of the Kumbh Mela festival, led by naked, ash-smeared holy men and accompanied by chants from Hindu holy texts. (Photo by Sanjay Kanojia/AFP Photo)

Children of the Roma community play as they cool off in a fountain in the main square of Pristina, Kosovo on June 14, 2017. (Photo by Armend Nimani/AFP Photo)

Young Japanese women dressed in colourful Kimonos take a photo of themselves as they gather for a ceremony marking the “Coming of Age Day” at the Toshimaen Amusement Park in Tokyo, Japan, 11 January 2016. The Coming of Age Day is the day to celebrate young people who turn 20 years old while the age of 20 is considered the beginning of adulthood and is the minimum legal age for voting, drinking and smoking in Japan. (Photo by Kiyoshi Ota/EPA)

Syrian refugee girl Nur El-Huda, 9, shows a drawing of her home in Syria, in her classroom in Yayladagi refugee camp in Hatay province near the Turkish-Syrian border, Turkey, December 16, 2015. Syria's conflict has left hundreds of thousands dead, pushed millions more into exile, and had a profound effect on children who lost their homes or got caught up in the bloodletting. The drawings of young refugees living in Turkey show their memories of home and hopes for its future. The pictures also point to the mental scars borne by 2.3 million Syrian refugees living in Turkey, more than half of them children. (Photo by Umit Bektas/Reuters)

A tomtit bird flies past a squirrel running on a fence after a snowfall in a park in Almaty, Kazakhstan, January 12, 2016. (Photo by Shamil Zhumatov/Reuters)

A bakery worker rides a bicycle as he carries fresh bread on his head in Cairo, Egypt, February 9, 2016. (Photo by Asmaa Waguih/Reuters)

Self-employed pedicab driver Danilo Guerra, 25, uses his mobile phone as he waits for clients in downtown Havana April 12, 2016. (Photo by Alexandre Meneghini/Reuters)