Mexican wrestler known as Mini Psycho walks inside the Basilica of Our Lady Guadalupe during the annual pilgrimage in Mexico City, Mexico August 25, 2016. (Photo by Carlos Jasso/Reuters)

“Mountain Goats, Colorado”. A herd of mountain goats huddle together on top of Mount Evans, Colorado during a lightning storm. This photo was selected out of more than 5,000 entries to go on display in “Wilderness Forever: 50 Years of Protecting America’s Wild Places”, a new photo exhibition at the Smithsonian’s National Museum of Natural History, which will run through summer 2015. (Photo by Verdon Tomajko/Smithsonian Wilderness Forever Photo Contest)

People take photos as an Ariane 5 space rocket with a payload of four Galileo satellites lifts off from ESA's European Spaceport in Kourou, French Guiana, on November 17, 2016. Ariane 5 successfully launched on November 17 four satellites which will be part of the Galileo global satellite navigation system. (Photo by Jody Amiet/AFP Photo)

A protester performs the symbolic death of a student demonstrator during a march near Congress where Chile's President Michelle Bachelet gives her annual address in Valparaiso, Chile, Thursday, May 21, 2015. Demonstrators are protesting the death of two students killed during an education reform march last week in Valparaiso and demanding more involvement in education reform. (Photo by Luis Hidalgo/AP Photo)

A prisoner from the Pedrinhas prison is carried to receive medical help after he was injured during a fight between rival gangs inside the jail, in Sao Luiz, capital of Maranhao state, January 8, 2014. The recent posting on a major Brazilian news website of a video filmed last December 17 by Pedrinhas prisoners of the decapitated and tortured bodies of rival inmates inside the jail has highlighted some of the problems present in the country's prison system which houses nearly twice as many prisoners as its capacity, according to official statistics. (Photo by Douglas Cunha/Reuters/O Estado do Maranhão)

The Greenland ice sheet is a vast body of ice covering 660,235 sq miles, roughly 80% of the surface of Greenland. It is the second largest ice body in the world, after the Antarctic Ice Sheet. Some scientists predict that climate change may be near a "tipping point" where the entire ice sheet will melt in about 2000 years. If the entire 2,850,000 cubic kilometres (683,751 cu mi) of ice were to melt, it would lead to a global sea level rise of 7.2 m (23.6 ft).

A group of women laugh at artwork referencing U.S. Republican presidential candidate Donald Trump made by the artist Hanksy and being sold at a temporary store in New York, U.S., June 4, 2016. (Photo by Lucas Jackson/Reuters)