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).

Young Japanese women pose with a green bear costumed person during the 'Earth Parade 2015' in Tokyo, Japan, Saturday, November 28, 2015. Ahead of the U.N. climate change summit in Paris starting this week, about 1,000 citizens and environmental activists took to the streets of Tokyo on Saturday, calling for strong actions to combat global warming. (Photo by Franck Robichon/EPA)

A graffiti, portraying a woman, is seen in Medellin, Colombia on November 19, 2017. Mural graffitis from different artists, street art can be seen in almost every city on Earth, but street arts raw power and potential for change was felt by me most intensively in Medellins Comuna 13, previously one of Colombias most dangerous neighbourhoods, in fact Communa 13 was constant battleground between gangs, narcos, paramilitaries and the government, but today you would hardly recognise it. (Photo by Juancho Torres/Anadolu Agency/Getty Images)

Buddhist monks walk past a statue of comic character the Hulk at Tamru temple in Samut Prakan province, Thailand, March 3, 2016. It’s a sign of changing times for Buddhism in Thailand when one sees temples, including Wat Tam Ru, using U.S. comic superheroes to attract children and teenagers into the religion. (Photo by Chaiwat Subprasom/Reuters)

A French riot police officer is surrounded by flames, during a demonstration against the controversial labour reforms of the French government in Paris on September 15, 2016. Opponents of France's controversial labour reforms took to the streets on September 15, 2016 for the 14th time in six months in a last-ditch bid to quash the measures that lost the Socialist government crucial support on the left. Scores of flights in and out of France were cancelled as air traffic controllers went on strike to try to force the government to repeal the changes that became law in July. (Photo by Thomas Samson/AFP Photo)

With the humpback calving season drawing to a close, here’s a look at some of Rita Kluge’s distinctive marine photos from the south Pacific. The Sydney-based photographer fell in love with whales after witnessing southern rights from the New South Wales coastline as they travelled to and from their feeding grounds in the Antarctic. She has since been to Tonga, where humpbacks breed and calf in winter months, to photograph them in the water. (Photo by Rita Kluge/The Guardian)