Alaska Warming Changes Offer Early Warning

Sept. 15, 2003 -- Our northern outpost is melting.

Permafrost is becoming soggy, temperatures are increasing, icebergs are thinning, roads are collapsing and entire villages are being forced to move as the ground beneath homes melts and erodes away.

And scientists say the changes in Alaska may be a sign of what's coming in the lower 48 and elsewhere in the world.

Rugged Researchers Do Science in the Arctic

"We know the signal [of climate change] in the Arctic is substantially larger than it is anywhere else on the planet," said Robert Corell, a former top National Science Foundation scientist who now heads research for an international group of researchers focusing on climate change.

"But if you want to see what's going to happen 25 years from now around the planet, just have a look at the Arctic," Corell added. "This is the canary in the coal mine for climate change of the planet."

Accelerated Warming

Corell heads the Arctic Climate Impact Assessment, or ACIA, a team of experts representing nations and native tribes with territory in the Arctic. Its aim is to assess the scope and effects of global warming in the north. OThe leaders met recently in Svalbard, Norway to work on a report that will be finished by the end of 2004.

But so far, their findings point to changes already under way in the Arctic and suggest that even bigger changes are yet to come.

ACIA's studies find that temperatures in Alaska have risen by 4 degrees Fahrenheit over the past 30 years. The increase is even steeper — 8 degrees — if only winter temperatures are considered. Temperatures have also risen globally, but so far only by about 1.5 degrees Fahrenheit over the last century.

Data from the National Climatic Data Center show that last year was Alaska's hottest on record and the past winter was the second-warmest ever recorded.

Although the cause of the warming remains uncertain, the majority of scientists believe it's related to the increased levels of pollutants from tailpipes and smokestacks. Pollutants containing gases including carbon dioxide and methane rise into the atmosphere and then trap heat, causing warming.

Modeling has suggested that continued warming could lead to a wide array of disruptions, from coastal damage as ice melts and sea levels rise to more intense cycles of drought and floods, along with more frequent outbreaks of tropical diseases such as malaria and yellow fever as warmer weather moves north.

In the Arctic, the signs of warming are already visible. Why has warming been more dramatic in the north? Gunter Weller of the Institute for Arctic Research at the University of Alaska, Fairbanks, explains it's due to a kind of snowball effect — literally.

The glare of an icy and snowy surface reflects sunlight, keeping ground temperatures cool. As some snow or ice melts, less sunlight is reflected and the ground warms up more quickly. That warming causes more snow and ice to melt and the cycle continues.

"It's a positive feedback loop that emphasizes warming," explained Weller.

Sinking Villages

This warming has already had very visible effects. Nearly 98 percent of glaciers and sea ice at Alaska's coast are in a state of melting, says Weller. That has contributed to a sea level rise of nearly a foot over the last 100 years.

Consequently, populations of seals that normally live on the icy surface are threatened, as are polar bears, since the massive animals use ice floats to hunt the seals.

Inland, another kind of ice is disappearing. Permafrost — rock and soil that remains below freezing for two or more years at a time — covers much of the state, creating a unique and sometimes challenging surface for construction and ecosystems.

In lower Alaska, patches of permafrost that had once created islands of trees within wetlands are melting, causing the trees to drown and die. Michael Ferrick, a research hydrologist with the military's Cold Regions Research and Engineering Lab, based in Hanover, N.H., has been observing this change in military-owned territory near Fairbanks.

"As the climate melts, the land subsides back into wetlands," he said. "Then you have a big ecological change."

Melting permafrost also carries consequences for developed areas. Two northwestern Alaskan native villages, Shismaref and Kivalina, must relocate because permafrost melt has led to extreme erosion, making the towns more vulnerable to storms.

Pipeline Problems

One of the largest, privately funded construction projects of all time — the Trans-Alaska Pipeline — is also affected by melting.

The pipeline, which runs for 800 miles from the North Slope to the ice-free Alaska port of Valdez, is buried underground in parts and, in others, rests on platforms. Since 75 percent of the line traverses permafrost, any melting requires attention and occasional repair work by the pipeline's maintenance company.

"That increases the price of your gasoline," argues Weller.

Corell argues that a warming Alaska will need to be part of the consideration of new, proposed drilling in the Arctic Wildlife Refuge in northern Alaska. More importantly, he says, it should be closely watched as a model for dealing with global climate change.

"We have to define areas where we can get smarter about warming," he said. "Watching the Arctic may help us avoid substantial changes elsewhere."