You're looking at Pine Island Glacier in Antarctica. It pushes more ice to the sea than any other glacier in the world. See that gigantic 18-mile-long canyon? That's the birth point of a new gargantuan iceberg.
The huge crack has been discovered by NASA's Operation IceBridge team, who took this photo aboard their retrofitted DC-8. The 18-mile-long crack goes as deep as 190 feet at some points and stretches 240 feet wide. It's opening faster than expected and, when it completes the process, scientists expect that it will originate a 300-square-mile iceberg.
It's the first time since 2001 in which such event has occurred. The Pine Island Glacier drains about 10 percent of the West Antarctica ice sheet. According to NASA, "scientists are concerned about the impact Pine Island's continued thinning will have on sea level."
The calving of this huge iceberg, however, seems to be part of a cyclical natural process not linked to global warming. According to Ted Scambos, the lead scientist at the National Snow and Ice Data Center, these "occur every few years, very similar in size and even shape. As a cyclical process, they are not part of the real climate-change/ice-shelf disintegration story."
The team is now working to install GPS markers alongside the opening line. I hope they install microphones too, because the sound of this thing cracking completely would scare the beejeezus out of Leonardo DiCaprio. [NASA Goddard Flickr and NASA]