Where global warming gets real inside Nasa’s mission to the north pole. For 10 years, Nasa has been flying over the ice caps to chart their retreat. This data is an invaluable record of climate change. But does anyone care? By Avi Steinberg. From the window of a Nasa aircraft flying over the Arctic, looking down on the ice sheet that covers most of Greenland, it’s easy to see why it is so hard to describe climate change. The scale of polar ice, so dramatic and so clear from a plane flying at 450 metres (1,500ft) – high enough to appreciate the scope of the ice and low enough to sense its mass – is nearly impossible to fathom when you aren’t sitting at that particular vantage point. But it’s different when you are there, cruising over the ice for hours, with Nasa’s monitors all over the cabin streaming data output, documenting in real time – dramatising, in a sense – the depth of the ice beneath.