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Climbing temperatures will affect oil patch Ocean access may improve, but thawing permafrost, less sea ice may require reengineering Kristen Nelson PNA Editor-in-Chief
Since the 1860s, temperatures around the world have increased about 1 degree Fahrenheit, and if computer models are correctly predicting the planet’s weather future, temperatures may increase by 10 degrees F by 2100 — and perhaps twice as much in high latitudes such as Alaska.
Retired University of Alaska Fairbanks professor of geophysics Gunter Weller reviewed what those changes can mean for the state in a Feb. 26 presentation to the House Resources Committee.
There is a natural greenhouse effect caused by CO2 in the atmosphere, Weller said, holding in heat. Without that natural greenhouse effect it would be 60 degrees F colder on earth, and life probably wouldn’t exist. But studies of bubbles in ice show an increase on CO2 in the atmosphere since the burning of fossil fuels increased with the industrial revolution, Weller said, and additional CO2 in the atmosphere increases the greenhouse effect.
“I think there is no longer a controversy about the effect of the greenhouse on the climate,” Weller said. “If there is any controversy… it is about the magnitude and the exact timing now.” Impacts for Alaska Meteorological stations around the Arctic recorded an increase of 1 degree Centigrade — about 2 degrees F — per decade between 1965 and 1995, Weller said, an average of about 5 degrees F. But in some areas of the Arctic, including Alaska, the temperature is up 10 degrees F over the past three decades.
Photographs from 1945 to 1995, he said, show there has been a substantial reduction in the extent of sea ice. And sonar records from U.S. nuclear submarines cruising under the ice of the Arctic Ocean are measuring a decrease in ice thickness: from an average of 4 meters in the Chukchi and Beaufort seas in the central Arctic in 1958-1976, to an average of 2 meters in the same areas in 1993-1997.
One result of warming is that permafrost melts. In Fairbanks, the average mean temperature is 28 degrees F, Weller said, “so you only need to raise the temperature by 4 degrees and the permafrost is beginning to thaw.” If temperature models are correct, that permafrost will be gone in 80 to 100 years. “And while it melts problems occur — roads and houses collapse and pipelines have to be reengineered.” Oil and gas impacts mixed As the temperature warms, glaciers will melt and the sea level will rise, as much as a meter (39.5 inches) over several hundred years, he said, affecting the Yukon Delta which is very low lying and also facilities on the North Slope.
Looking at short-term impacts, Weller said offshore oil and gas exploration in the Arctic would benefit if there is less sea ice and ship transportation to the North Slope would be easier.
“On the other hand, offshore exploration also relies fairly strongly on ice roads along the Beaufort coast in the Prudhoe Bay area,” he said, and a warmer temperature will make ice roads more difficult to build.
As the sea ice recedes, coastal facilities and artificial islands will face stronger storm surges and erosion problems. And permafrost thaw will affect oil and gas pipelines, Weller said, and some will have to be reengineered.
What will the cost be in Alaska?
“We’ve reached the stage now,” Weller said, “where we’re talking with economists in order to really put dollar values” on the changes for Alaska.
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