By Bob McDonald, Quirks & Quarks

An international study released this week has provided the best picture yet of the 344 billion tons of ice that are lost from Antarctica and Greenland each year due to climate change. Ironically, at the same time, a supertanker carrying liquid natural gas, one of the fossil fuels responsible for changing the climate, is making the first winter crossing of the Arctic Ocean on a shortcut between Europe and Japan.  

The study, called the Ice sheet Mass Balance Inter-comparison Exercise (IMBIE), a joint effort by NASA and the European Space Agencies, was an attempt to solve the problem of wildly different estimates of how much ice is being lost, from many studies by independent groups in different regions over the past two decades. Most studies have shown that ice is being lost at an accelerating rate, but some have shown either no loss at all or even gains. This effort brought everyone together to get a truer picture of what's happening to continental ice at both poles.

The group of 47 glaciologists from 26 institutions combined data collected by all the different studies going back to 1992, as well as measurements from satellites and GPS sensors on the ground, to calculate the mass of both ice sheets and how that has changed over time. The results showed that there is, indeed, an overall decline in ice from both regions, and that the loss has accelerated in the last decade.

However, the loss of ice is not the same everywhere.  

One area in Eastern Antarctica is actually growing ice, due to local weather conditions, a fact that has been used by climate deniers to show how global warming is not actually happening. But that growth is overshadowed by greater losses in the western part of the continent and the Antarctic Peninsula, which runs north towards the tip of South America. Those ice sheets are being melted from below by warmer ocean currents that erode the floating ice along the shorelines at the mouths of glaciers, which makes the glaciers flow faster down the mountainsides.

Greenland is losing ice at an even faster rate, for the same reasons. Altogether, the Earth is now losing almost three times as much ice from the ice sheets as it was in the early 1990s. This melting has already contributed to 0.59 mm of sea level rise per year, which doesn't sound like much. But on a global scale, that's a lot of water being added to the ocean - water that can increase the effect of storm surges such as the ones from Hurricane Sandy that struck New York.

If all the ice in Antarctica and Greenland were melted into the seas, most coastal cities would be completely flooded over. Fortunately, that's not going to happen immediately, but scientists are concerned that the rate of ice melting is accelerating.

But while climate scientists are concerned about the increasing loss of polar ice, industry is taking advantage of it. This month, the supertanker Ob River departed from Norway carrying 150,000 cubic metres of liquefied natural gas. The ship is attempting the first winter crossing of the Barents Sea north of Russia on its way to Japan. The route across the Arctic Ocean shaves 20 days off the normal transit through the Panama Canal, which equates to a 40 per cent saving in fuel. Ships that attempt this route usually do it in the summer, when most of the ice is either gone or broken up. This ship is being escorted by a Russian nuclear-powered ice breaker, but mostly its passage is made possible by the tremendous loss and thinning of ice in the North from climate change, which makes it easier for a ship to pass through.

This is the tip of the melting iceberg for the shipping industry. The Arctic Ocean will soon become a supertanker superhighway.

In nature, there are feedback loops, where one effect causes another, which, in turn, feeds back into the first. So, for example, warm air melts ice, exposing dark sea water, which absorbs heat faster than ice, which creates more warm air that melts the ice faster, exposing more dark sea water, and so on, in an accelerating way until all the ice is gone.

In this case, the feedback is between nature and industry, where fossil fuel emissions are warming the climate and melting the ice so that industry can take advantage of open water to expand its operations and increase carbon emissions further.

From a business standpoint, an ice-free Arctic is a win situation, but the billions of dollars to be gained in the short term comes with a cost of billions of tons of ice lost in the long run.