Arctic thaw
Climate change is playing havoc with rare species and a proud way of life
Activity on deck and in laboratories below is continuous, with individual scientists often working 18-hour days. Dredges, nets, water samplers, seines, and instruments go in and out of the sea constantly to chart how nutrients cycle through a trench in the ocean floor called the Barrow Canyon that dissects the shallow continental shelf and runs into the abyssal deeps farther north.
"The dinner bell is ringing, that's for sure," says one of the 40-plus scientists on board, oceanographer Lou Codispoti of the University of Maryland Center for Environmental Science. With more sunlight and a powerful current of warm Pacific water flowing into the region, the waters burst with microscopic life. Algae blooms are spreading north. Plankton species appear to be undergoing rapid changes, with southern types moving in rapidly.
Codispoti said one water sample had the highest oxygen content he'd ever heard of anywhere. The nutrient richness feeds clouds of flea-size copepods, the base of the animal food chain. "These things are basically sacks of fat," says Carin Ashjian of Woods Hole Oceanographic Institution as she pointed to magnified images on a video screen in the ship's main lab.
The bounty in the increasingly open, ice-free sea may be why salmon are thronging Barrow's lagoons and may augur a full invasion of Pacific fish in regions that have had relatively few fish before, says Jackie Grebmeier of the University of Tennessee, organizer of the icebreaker-borne study.
Predators. The Arctic norm has been a "benthic ecosystem," with most of the action on the bottom, where crustaceans, mollusks, and marine worms abound. They in turn are the prime food source for walruses, many seals, and gray whales. New midwater predators could reduce the food reaching the bottom, making life tough for the Arctic's marine mammals.
More worrisome, says microbiologist Grebmeier, is that a future Arctic without a lid of ice near shore could shift ocean plants into deep water, further starving marine life in the shallows. Walruses and seals that use the ice as a foraging base and sanctuary for their young would find themselves unable to reach the bottom. And if the walruses and seals wane, so will the polar bears that eat them.
As for the bowhead whales, no one knows how their patterns may shift. To Nusunginya, the peril is clear. "If we don't adapt to this climate change, we may be at the end. We live off the land. For us the ice is an extension of the land." But Barrow's hunters are nothing if not resourceful and technically savvy. Most are optimistic that, just as they quickly embraced Yankee whale guns in the last century, they can devise new ways to find bowheads wherever they are. Nusunginya says, "Whatever it takes, boats with more range or bigger engines, we'll find them. We have no choice. It is in our blood."
Temperature Variations from 1951-to-1980 Average
(in Fahrenheit)
History shows that Arctic air-temperature variations exceed those of the globe as a whole. Computer models show that coming decades will bring even more dramatic warming. Floating sea ice is visibly shrinking already, and many researchers predict a mostly ice-free Arctic Ocean every summer by midcentury.
[chart labels]
1900; Global average; 1950; Warmer Arctic avg.; Cooler Arctic avg.; Since 1970, Arctic sea ice is 40 percent thinner; 2000
-3.0
-2.0
-1.0
0
1.0
2.0
3.0
Sources: Goddard Institute for Space Studies, National Snow and Ice Data Center
Rob Cady--USN&WR
Arctic Ocean map
[Map labels]:
Current ice extent
Average ice extent (1979-2000)
UNITED STATES
CANADA
RUSSIA
GREENLAND
Barrow
ALASKA
Arctic Circle
Sources: Goddard Institute for Space Studies, National Snow and Ice Data Center
Rob Cady--USN&WR
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