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 reindeer is seen as people visit ice sculptures illuminated by coloured lights at the Harbin Ice and Snow Festival to celebrate the new year in Harbin on January 4, 2017. (Photo by Nicolas Asfouri/AFP Photo)

Canada's Yuri Nazarkin carves Star Wars character C-3PO (R) and R2-D2 for the ice sculpture festival in Liege, Belgium, November 13, 2015. (Photo by Eric Vidal/Reuters)

A hostage runs towards a police officer outside Lindt cafe, where other hostages are being held, in Martin Place in central Sydney December 15, 2014. Two more hostages have run out of the cafe at the center of a siege in Sydney, Australia's largest city, according to a Reuters witness at the site. The two women were both wearing aprons indicating they were staff at the Lindt cafe where a gunman has been holding an unknown number of hostages for several hours. Three men had earlier run out of the cafe. (Photo by Jason Reed/Reuters)

As these Cafe Taina Coffee ads explicitly assert, there are "times when sleeping is not an option."
Executed by Giovanni + Draft FCB, this animated advertising campaign captures two situations in which awareness is of necessity: when you're trapped in a jail cell with a large creepy inmate, and when a fellow castaway is equally prepared to resort to cannibalism as you are. It's very lucky that the cartoon characters in the Cafe Taina Coffee ads had a bag of the grind handy, or one tired blink may have been their last.

Iceland is known as the land of fire and ice and these images capture the essence of that perfectly. Incredible ever-changing landscapes demonstrate the contrast between the freezing ice and burning skies that dominate Iceland's beauty. The stunning pictures taken by photographer Lurie Belegurschi show the breathtaking and utterly unique ice plains formed in sub-zero temperatures. (Photo by Lurie Belegurschi/Caters News)

A female swimmer reacts after finishing the competition in a pool carved from thick ice covering the Songhua River during the Harbin Ice Swimming Competition in the northern city of Harbin, Heilongjiang province, January 5, 2016. The swimming competition was held on the official launch day of the Harbin International Ice and Snow Sculpture Festival. (Photo by Aly Song/Reuters)

Customers drink a coffee as several cats roam at Cat Cafe Melbourne on July 25, 2014 in Melbourne, Australia. Cat Cafe Melbourne is Australias first cat cafe. The cafe has several cats from rescue shelters which live at the premises. Patrons can watch and play with the cats while enjoying a coffee. Cat Cafes are becoming known world wide, the first opening in Taiwan in 1998. (Photo by Scott Barbour/Getty Images)