Small transportation boats, known as bumboats, leave trails of light as they travel across Marina Bay past the skyline of Singapore in this photo taken in 2004. Singapore holds a Jubilee weekend from 7 to 10 August to celebrate the 50th anniversary of its independence. Fifty years ago, hundreds of small boats lined the Singapore river in the city centre. Today, most small boats are gone, except a handful of neon-lit tourist ferries. Maritime trade is still the backbone of the city-state but after decades of rapid growth Singapore, which at less than half the size of London is among the world’s most densely populated nations, is also a popular tourist destination and a thriving global financial hub. (Photo by Edgar Su/Reuters)

Mount Etna erupts near Sicily, Italy on March 15, 2021. This is the thirteenth time in twenty-eight days. During the early evening of 14 March and the night between 14 and 15 March a strombolian activity at the Southeast Crater gradually increased, leading to a paroxysmal event which had its peak around 01:00 am, ash blown by the wind touched the south-southeast slope of the volcano reaching also Catania, the event ceased completely around 3:45, photo taken from Milo near Catania on March 15, 2021. (Photo by Salvatore Allegra/Anadolu Agency via Getty Images)

A young girl splashes through a waterfall at a park in Washington, DC, on June 28, 2021, as a heatwave moves over much of the United States. Swathes of the United States and Canada endured record-setting heat on June 27, 2021, forcing schools and Covid-19 testing centers to close and the postponement of an Olympic athletics qualifying event, with forecasters warning of worse to come. The village of Lytton in British Columbia broke the record for Canada's all-time high, with a temperature of 46.6 degrees Celsius (116 Fahrenheit), said Environment Canada. (Photo by Jim Watson/AFP Photo)

Zhu Jianqiang, or “strong-willed pig”, famous for surviving more than a month buried in the ruins after the magnitude-8.0 Wenchuan earthquake in 2008, feeds on food sent by admirers wishing it a safe winter in Jianchuan Museum, Chengdu city, southwest China's Sichuan province, 11 January 2021. (Photo by Rex Features/Shutterstock)

A woman walks in a street in freezing weather of –24 degrees Celsius in Omsk, Russia on January 13, 2021. Daytime temperatures have been below –20 degrees Celsius in the Omsk Region since 25 December 2020. (Photo by Yevgeny Sofiychuk/TASS)

Monster girl Crazy Sa-ya, an iconic Harajuku girl and a staff member of the cafe, wearing a face mask poses for a photograph at Kawaii Monster Cafe, amid the coronavirus disease (COVID-19) outbreak, in Tokyo, Japan on January 31, 2021. (Photo by Issei Kato/Reuters)

A model is seen posing in front of Olivier Rousteing, during the Balmain Pre-Fall 2021 Collection photoshoot by Olivier Rousteing, from Saint-Honore Flagship store in Paris, on December 09, 2020 in Paris, France. (Photo by Edward Berthelot/Getty Images)

A Sumatran elephant calf receives medical attention at the Saree elephant conservation centre in Saree, Aceh province on February 15, 2021, following the three week-old pachyderm's rescue in Pidie district after being stuck in mud. (Photo by Chaideer Mahyuddin/AFP Photo)