Each year in June, just before all the sea ice has melted, climate scientists at the Danish Meteorological Institute head out by dog sled onto the Greenland sea ice to collect their instruments. Typically the dogs walk on ice for this task, but because of warming temperatures, this year the dogs were splashing in ankle-deep water.
The photo above was taken on June 13 by climatologist Steffen Olsen from the Center for Ocean and Ice at the institute. Olsen's colleague, Rasmus Tonboe, tweeted the image, saying "rapid melt and sea ice with low permeability and few cracks leaves the melt water on top."
Olsen said the ice was about 1.2 meters (3.9 feet) thick. It was taken in the middle of Inglefield Bredning, a fjord in northwestern Greenland. He tweeted that the dogs weren't running on the ice sheet, but on sea ice flooded by surface meltwater.
"This year the expedition to retrieve the instruments – by dog-sled, still the most practical way to get around in this region at this time of year – ran into a lot of standing water on the sea ice," Ruth Mottram, climate scientist at the institute, told The Guardian. "The ice here forms pretty reliably every winter and is very thick, which means that there are relatively few fractures for meltwater to drain through. Last week saw the onset of very warm conditions in Greenland and in fact much of the rest of the Arctic, driven by warmer air moving up from the south."
Those conditions led to a lot of melting ice, she said. Because the ice is thick in the area and there are no fractures where it can drain, the water pools on the surface. Events like this aren't unusual, but they typically don't occur until later in the summer.
Is it global warming?
Mottram told The Guardian that the temperatures are out of the ordinary but it's too early to say whether global warming has played a part because it's "still a weather-driven extreme event, so it's hard to pin it down to climate change alone."
However, she said: "Our climate model simulations expect there to be a general decline in the length of the sea ice season around Greenland, [but] how fast and how much is very much dependent on how much global temperature rises."
As for the photograph, Olsen said he was overwhelmed by all the interest it has received.
"The photo documents an unusual day," Olsen tweeted. "I learn now that it is even more symbolic than scientific to many. Tend to agree."