A salsa dancer performs in the “Salsodromo” parade, which marks the start of the Fair of Cali, Colombia, December 25, 2015. Picture taken December 25, 2015. (Photo by Jaime Saldarriaga/Reuters)

Workers carve ice art works at Harbin Ice and Snow World one day before the 32th Harbin International Ice and Snow Festival in Harbin city, China's northern Heilongjiang province, 04 January 2016. The festival will run from 05 January to 05 February. (Photo by Wu Hong/EPA)

It might have been foggy in the Willamette Valley, but Cerridwen Martin was able to revel in a view of the top of the clouds from the summit of Spencer Butte in Eugene, Ore., on Tuesday, December 16, 2014. Martin was joined by Joe Martinson, right, for the 1.1 mile trek. Fog shrouded much of the city for most of the day. (Photo by Andy Nelson/AP Photo/The Register-Guard)

This picture taken on November 11, 2016 shows participants releasing a hot- air balloon during the Tazaungdaing Lighting Festival at Taunggyi in Myanmar' s northeastern Shan State. The skies of central Myanmar were set ablaze this week with the beginning of the Taunggyi fire balloon festival, one of the most beautiful and dangerous celebrations in Asia. Brightly coloured balloons with hundreds of homemade fireworks woven into their frames are sent soaring into the night sky, showering down cascades of sparks onto adoring crowds. (Photo by Ye Aung Thu/AFP Photo)

Rare images of wild tigers in Bhutan, captured by camera traps, show tigers and other animals using high-altitude wildlife corridors which are lifelines to isolated tiger populations and critical to genetic diversity, conservation and growth. Here: A wild Bengal tiger (Panthera tigris tigris) captured on a camera trap in corridor eight at an altitude of 3,540 metres in Trongsa, Bhutan. (Photo by Emmanuel Rondeau/WWF UK/The Guardian)

A policeman controls traffic at 42nd Street and 7th Avenue as New York City remains without electricity caused by a blackout that affected the entire city and most of the eastern part of the nation August 15, 2003 in New York, New York. More than 50 million people were affected by the outage, in Toronto, Detroit, Cleveland and New York City. (Photo by Jose Jimenez/Primera Hora/Getty Images)

Qian Hao's imported Pekingese dog, Mixiu, runs in a park in Beijing, China, February 8, 2018. (Photo by Thomas Peter/Reuters)

Tiny pieces of space rocks, called meteorites, are seen burning in the atmosphere over the night sky near Salgótarján, some 109km northeast of Budapest, Hungary, 21 April 2018 (issued 22 April 2018). (Photo by Peter Komka/EPA/EFE)