Indian tourists walks during heavy snowfall by Dal Lake in Srinagar on January 6, 2017. The sub-zero temperatures has frozen many water bodies in Kashmir and even drinking water taps have frozen at some places. (Photo by Tauseef Mustafa/AFP Photo)

Revelers dressed as Santa Claus drink outside at a bar during the annual SantaCon event December 10, 2011 in New York City. SantaCon is a mass gathering of revelers dressed as Santa Claus who take to the streets in cities across the country before Christmas. (Photo by Allison Joyce/Getty Images)

The Grand Canyon Skywalk is a transparent horseshoe-shaped cantilever bridge and tourist attraction in Arizona near the Colorado River on the edge of a side canyon in the Grand Canyon West area of the main canyon. USGS topographic maps show the elevation at the Skywalk's location as 4,770 ft (1,450 m) and the elevation of the Colorado River in the base of the canyon as 1,160 ft (350 m), and they show that the height of the precisely vertical drop directly under the skywalk is between 500 ft (150 m) and 800 ft (240 m).

A massive positive cloud-to-ground lightning strike hits in Coolidge, Arizona, 31 August 2016. Thousands of rain drops merge to form mammoth travelling sheets of water in these breathtaking monsoons. Veteran storm chaser and photographer Mike Olbinski captured the stunning beauty of monsoons in timelapses and stills while chasing storm systems across America. (Photo by Mike Olbinski/Barcroft Images)

The photography of Art Wolfe covers the globe, capturing landscapes, wildlife, and cultures from every continent; here he talks through a selection of his favourite images. Art Wolfe is an American photographer and conservationist. His photographs have been noted by environmental advocacy groups for their “stunning” visual impact. Here: Snowy owlets (Bubo scandiacus), Arctic National Wildlife Refuge, Alaska, USA. (Photo by Art Wolfe/Art Wolfe Stock)

An Afghan girl carries water on her back as she climbs a hill in Kabul, Afghanistan February 20, 2017. A growing population is straining water supplies in Afghanistan's capital, forcing those who can afford it to dig unregulated wells ever deeper to tap a falling water table. Finding water in arid Afghanistan is virtually always a challenge, but a drop in the groundwater level in Kabul caused by overuse and drought is making it even more difficult for residents, especially the poor. (Photo by Omar Sobhani/Reuters)