Cold comfort
A FLOATING MOUNTAIN of grey and white ice, castellated and crevassed like an Alpine ridge, the iceberg is vast: the size of two aircraft carriers, maybe more. Scale is hard to judge in the Arctic because of its ubiquitous icy-white backdrops. Yet much the biggest part of the icebergperhaps nine times the size of the visible partis submerged and invisible. As it drags along the bottom of the Jakobshavn Fjord, this mass of ice could cause earth tremors. Were it to flip over, pressed by sea ice from behind, it might cause a tsunami. The Arctic will retain its power to amaze for a long time. Yet it is now changing beyond the usual regional and annual variations in sea-ice formation, glacier melt and so forth. The Arctic is clearly melting. Its floating ice cap is shrinking and thinning and its glaciers are retreating. By the end of this century, maybe much sooner, there will be frequent Arctic summers with almost no sea ice at all. In the balance Why does this matter? For millennia man has been changing the landscape, hacking and burning forests and ploughing up grasslands. This is how societies have evolved and prospered. Why should the melting Arctic, a product of man-made global warming, be any different? For most people living there, it is not. Many welcome the changes. They certainly know what is happening. No one in Greenland would think of climate change as a theory: it's observation, says Minik Rosing, a Greenlandic scientist. Yet many would prefer their winters a bit less chilly. They are also looking forward to the rich opportunities a warmer Arctic will open up in resource development, shipping and the service industries that will flourish around them. These new Arctic industries will not come about overnight and may well deliver less than their cheerleaders promise. Even as the ice recedes, the Arctic will remain extraordinarily cold, dark, remote, expensive and difficult to operate in. But Arctic oil could make a significant contribution to global suppliesmaybe as much as 10% of the total. That will be of huge benefit to Arctic economies. So those greens who have set their hopes on the eco-attuned Inuit or Scandinavians taking a stand against Arctic warming are likely to be disappointed. The best hope is that Arctic governments will continue to develop the region as carefully and harmoniously as they have been doing in recent years. That is no small thing. The Arctic is probably the arena where Russia interacts most usefully with the Western world. And all Arctic countries are opening their offshore areas to exploration with caution: for oil companies, the Arctic is one of the world's most tightly regulated regions. All this is good, but it is not the main point. The impending enrichment of Arctic countries would not compensate for the costs of runaway Arctic warming. Arctic species, habitats and quite possibly whole ecosystems would be lost. No Arctic countrynot even Russia, which has a poor history of conservationcould contemplate wreaking such environmental havoc unilaterally. Yet all are happy to profit from it. That makes the Arctic a textbook illustration of the commons-despoiling tragedy that climate change is. The costs to the world are likely to be greater than those to the Arctic, however. Arctic glaciersincluding the Greenland ice sheetare melting and disintegrating faster than expected. If this were to continue over a couple of centuries, there would be a strong chance of catastrophic rises in sea levels; this alone might cost the world more than it stands to benefit from Arctic resources. As a symptom of global warming, moreover, the warming Arctic is indivisible from the manifold costs it will entail. The World Bank estimates the cost of adapting to climate change between 2010 and 2050 at $75 billion-100 billion a year; other estimates are higher. Watch our animation of the receding Arctic ice-shelf and the shipping routes it could unlockSooner or later such arithmetic is going to force governments to get serious about dealing with climate change. It is already clear what is required: policies to put an appropriate price on carbon emissions, through a tax or market-based system, that is sufficient to persuade polluters to develop and adopt cleaner technologies. These are already available, and so is the ingenuity needed to force down their costs and bring them to market. Indeed, it is evident in the Arctic: the technological feats that oil companies display there are inspiring. With prompt action, the worst outcomes of a warmer Arctic can still be avoided. The shrinking ice cap may find a new equilibrium. Most of the permafrost may remain frozen. But the Arctic will nonetheless be radically changed, to the detriment of a unique polar biome. This much is already inevitable.