Pushing through the ice floe from a glacier along the wild coast of Greenland, the engine on our converted fishing boat strained as it slowly propelled the vessel through hundreds of small chunks of floating ice that cracked and scraped their way ominously against the hull.
We chugged along slowly, passing jagged white icebergs the size of houses, then giant blue icebergs, gifted their ethereal colour by compressed snowfall, until we rounded a corner in a fjord, and could see the face of the enormous Qooroq glacier in the distance and the pristine Greenland ice sheet looming behind. It was a breathtaking vision of our fragile frozen North.
I was travelling in Greenland while filming for Arctic Live, a new series for BBC2 in which I’ll join fellow presenters Kate Humble and Gordon Buchanan to broadcast live over three nights from Churchill in northern Canada, on the edge of the Arctic. If all goes well, we hope to be there just as scores of polar bears arrive in town. They wait for sea ice to form then head off on their winter hunt. Watching the bears, our largest land carnivores, should make for an extraordinary spectacle.
Within the live broadcasts from Canada will be other films we have shot during recent months across the wider polar region, which try to capture the drama of Arctic life. I went fishing for giant crabs that are crawling around northern Norway, had a close encounter with a Siberian motorcycle gang, and explored a spooky Soviet bunker that once stored nuclear warheads for use during a Cold War apocalypse.
But it was filming the environment of the Arctic that I found most memorable – and frightening. Our planet is warming, and the Arctic is heating faster than anywhere else. Vast areas of ice that cover the Arctic Ocean are now melting. There are scientists who believe that eventually the centre of the Arctic will be free of ice during the summer, and ships will be able to sail to the North Pole.
The consequences will be felt far beyond the Arctic. White ice reflects sunshine, but when it melts, darker seawater absorbs more solar energy, driving further climate change. Without ice in the Arctic acting as a natural air conditioner, winds that blow to Greenland and Siberia will also be warmer, further increasing melting and heating the planet yet more.
The collapse of Arctic sea ice is an enormous event, possibly the largest change on the surface of our planet that humans have ever witnessed, and not surprisingly scientists can’t fully predict all of the consequences.
Glacial ice sheet in Greenland
What does seem clear is that Greenland in particular is a time bomb. Just 57,000 people live around the edges of the world’s largest island, because most of the island is covered by the enormous Greenland ice sheet, a colossal reservoir of frozen freshwater, more than 660,000 square miles in size and on average more than one mile thick.
The sheet is now melting at an astonishing rate. It’s thought to have lost more than one trillion tons of ice in the past five years, far more than is replaced by snowfall. If it melts entirely, and many scientists believe that’s a real possibility during this century or the next, then the size and thickness of the sheet means its loss would raise global sea levels by around seven metres. Billions of tons of melt water pouring into the sea could spell disaster for coastal communities and cities such as New York, and entire countries such as Bangladesh, with hundreds of millions of people affected.
After seeing the sharp edge of the Greenland ice sheet at the Qooroq glacier, I hopped aboard a helicopter patrol that monitors rogue icebergs and warns cruise boats when they drift into shipping lanes. We flew along the coast and then the pilot turned inland, rising to reveal the vastness of the ice sheet, which stretched away beyond the curve of the planet.