A study by NASA's Jet Propulsion Laboratory which will be published in Geophysical Research Letters this week shows that arctic ice melted at record rates this year. The shrunken ice-levels are creating new potential trading routes, but this benefit is overshadowed by many other costs including rising sea-levels and habitat destruction for the arctic ecosystems.

Retreating Ice: A blue Arctic Ocean in summers by 2013?
The Arctic ice cap shrank so much this summer that waves briefly lapped along two long-imagined Arctic shipping routes, the Northwest Passage over Canada and the Northern Sea Route over Russia.

Over all, the floating ice dwindled to an extent unparalleled in a century or more, by several estimates.

. . . Astonished by the summer's changes, scientists are studying the forces that exposed one million square miles of open water - six Californias - beyond the average since satellites started measurements in 1979.

At a recent gathering of sea-ice experts at the University of Alaska in Fairbanks, Hajo Eicken, a geophysicist, summarized it this way: "Our stock in trade seems to be going away." Scientists are also unnerved by the summer's implications for the future, and their ability to predict it.

Complicating the picture, the striking Arctic change was as much a result of ice moving as melting, many say. A new study, led by Son Nghiem at NASA's Jet Propulsion Laboratory and appearing this week in Geophysical Research Letters, used satellites and buoys to show that winds since 2000 had pushed huge amounts of thick old ice out of the Arctic basin past Greenland. The thin floes that formed on the resulting open water melted quicker or could be shuffled together by winds and similarly expelled, the authors said.

These unprecedented melting rates alarmed the scientists, and a new concern is that their computer models may be too conservative to make accurate predictions in the future. Previous estimates suggested that the blue arctic ocean would not be a reality until around 2040 , twenty-seven years later than the new data indicates.

The pace of change has far exceeded what had been estimated by almost all the simulations used to envision how the Arctic will respond to rising concentrations of greenhouse gases linked to global warming. But that disconnect can cut two ways. Are the models overly conservative? Or are they missing natural influences that can cause wide swings in ice and temperature, thereby dwarfing the slow background warming?

The world is paying more attention than ever. Russia, Canada and Denmark, prompted in part by years of warming and the ice retreat this year, ratcheted up rhetoric and actions aimed at securing sea routes and seabed resources.

Proponents of cuts in greenhouse gases cited the meltdown as proof that human activities are propelling a slide toward climate calamity.

Arctic experts say things are not that simple. More than a dozen experts said in interviews that the extreme summer ice retreat had revealed at least as much about what remains unknown in the Arctic as what is clear. Still, many of those scientists said they were becoming convinced that the system is heading toward a new, more watery state, and that human-caused global warming is playing a significant role.

At a loss to attribute the cause to other factors, even those skeptical of global warming are now changing their minds. Human-caused global warming is becoming the only rational explanation for these mass changes.

For one thing, experts are having trouble finding any records from Russia, Alaska or elsewhere pointing to such a widespread Arctic ice retreat in recent times, adding credence to the idea that humans may have tipped the balance. Many scientists say the last substantial warming in the region, peaking in the 1930s, mainly affected areas near Greenland and Scandinavia.

Some scientists who have long doubted that a human influence could be clearly discerned in the Arctic's changing climate now agree that the trend is hard to ascribe to anything else.

"We used to argue that a lot of the variability up to the late 1990s was induced by changes in the winds, natural changes not obviously related to global warming," said John Michael Wallace, a scientist at the University of Washington. "But changes in the last few years make you have to question that. I'm much more open to the idea that we might have passed a point where it's becoming essentially irreversible."

The article then proceeds to explain that some natural variation may change this direction, but in the long-term human impacts will override the limits of any residual natural variation factors.

While some may want to close their eyes to this ever increasing problem, the rest of us should be discussing paradigm shifts to address these concerns. The natural world has no sympathy for us. We must make the necessary changes or face the consequences of our actions.