Arctic Flight Shows Substantial Ice Melting

Every 101 minutes or so, a Department of Defense imaging satellite circles the Earth, capturing images from the equator to the polar ice caps. It's that DOD drone (colorfully named the DMSPF-17) that monitors geologic changes, such as the decreasing size of the Arctic and Antarctic ice covers. The images it snaps are the ones most people see of the Earth's two white domes, which have been steadily diminishing for the past decade.

But step closer to the Earth—about 250 miles closer—until you're just above the surface, and the picture becomes more vivid.

Skimming over the top of the world feels a bit like being on a different planet, according Rick Steiner, a marine conservation researcher at the University of Alaska. For the past two years, Steiner has led research missions flying low over thousands of miles of Arctic seas for a handful of polar climate scientists, some of whom work for the federal government. He times the daylong voyage to coincide with the time of year when sea ice is at a minimum, the exact end of summer melting in mid-September, before the autumn cool begins to refreeze some of the water. Having lived in Alaska for 30 years, Steiner can tell you in personal detail how the minimum has shrunk from year to year. He calls the voyage his annual "bearing witness to the Arctic crisis" trip.

The crisis has been mapped out in precise detail in slide shows and research papers, with startling statistics. The past three summers have seen the lowest ice volume ever recorded, according to data released annually by the National Snow and Ice Data Center (NSIDC). The sea-ice minimum in 2007 (1.6 million square miles) was the single lowest year, with nearly 40 percent less ice than the seasonal average recorded over the past three decades. And the problem is only expected to worsen. As the ice melts, it releases highly concentrated carbon and methane that is locked in the permafrost, creating an accelerating warming loop. An additional compounding factor is that dark oceans absorb more of the sun's energy than light-colored ice, which reflects a large portion of it. That means that the more ice melts over the summer, the more open ocean there is, which leads to more absorbed energy and warmer oceans, which means that less ice forms the following winter, which leads to even more open ocean the following year. Early this past summer, researchers thought 2009 would be even worse than 2007 in terms of melting, until a late-arriving wind from the equator brought cool air that prevented even more melting. NSIDC director Mark Serreze calls it a "small blip" on a downward-sloping line.

"When you're actually looking out the window and seeing mile after mile of warm ocean water where there used to be sea ice that you once walked around on, it gives you the certainty that something major is going on there," says James Overland, a marine environmental researcher with the National Oceanic and Atmospheric Administration, one of the handful of researchers on the flight. The thickness of the ice and water temperatures—which were also measured at disturbingly high levels by Steiner and his team this year—are also measurements you can't make by peering at satellite images.

The Antarctic has problems of its own; last month researchers discovered the continent's largest glacier melting four times faster than initially projected. But of the two poles, the Arctic is more volatile. The smallest changes in global climate can affect millions of square miles of open sea there, since it has a smaller ice cover than its South Pole counterpart. It's also a territory of immense interest to the U.S. Just days before President Bush left office this past January, he signed a directive ordering further study of the Arctic region and the natural resources it might offer. "High levels of uncertainty remain concerning the effects of climate change and increased human activity in the Arctic," the directive said, encouraging skeptics who claim that climate change is still a debatable proposition. In Alaska, Steiner was incredulous, and he has since recommended to Obama administration officials to change the directive. (The White House Council on Environmental Quality submitted a report to the president last month highlighting the urgency of Arctic issues.)

Possible disagreements about human contribution to global warming notwithstanding, a melting Arctic does bring up questions about sovereignty and national security. Russia already made a play in 2007 to claim the northernmost parts of the globe, with an eye on the valuable oil reserves below. But more generally, less ice means more area for the U.S. Coast Guard to monitor. Rear Adm. Chris Colvin runs the Coast Guard's district office in Juneau, Alaska, and has seen the effect of longer summers and warmer winters in the region. "Our concern is an increase of [human] activity up here, which is definitely the case," says Colvin. Much of that increase, he says, is tourism vessels and oil companies that see dollar signs in the newly accessible ocean and seabed.

Shipping vessels may pose a future problem. Transport analysts started calculating in 2006 that with increased melting caused by global warming, ships could save thousands of miles by exchanging equatorial routes for a more direct passage along the northern parts of Asia and North America and down through the Bering Strait. Most of the insurance companies that cover transport vessels aren't yet willing to insure valuable goods passing through dangerous and potentially icy waters, but future melting and longer summers could remove that obstacle, requiring additional military attention in the region. "If ships start passing through [the Bering Strait], we're going to have concerns up there," says Colvin. (That's one reason why the Coast Guard is the leading sponsor of Steiner's annual trip.)

While the world awakens to the increasing seriousness of a melting Arctic, Steiner and his colleagues have moved on to the question of how increased Arctic temperatures will affect the rest of the globe. Less ice locked up at the poles means more water in the oceans and higher ocean levels. What that means for the environment—and consequently for the economies and politics—in coastal areas all over the world is still unclear.

Effects can also be felt by the critters on the ground. On a good day, with a clear cloud cover, biologists can spot signs of Arctic wildlife from satellite images. On-the-ground censuses have highlighted the dangers posed to Arctic wildlife, most significantly polar bears, who may find themselves stranded with few food options on floating bits of melting ice. For his part, Steiner has seen some changes himself on his annual flights. "Last year we saw about seven polar bears, thousands of walruses, and a handful of seals," he says. This year they saw none.

Government estimates suggest that it may take 30 years until the Arctic is ice-free during the summer, although more alarmist voices have set the date as close as 2013. Crunching the numbers and basing his assessment on his team's observations, Steiner foresees a completely ice-free summer within the next decade. By then, he fears, the crisis he sees worsening each year will have turned into a catastrophe.