Seaman Sikuliaq reporting for duty, Captain. The low rumbling of the engine of the RV Sikuliaq was music to ocean scientists’ ears last week during a 23-day cruise to test how the newest addition to the U.S. oceanographic fleet handled icy seas. Starting from Dutch Harbor on the Aleutian island of Amaknak in Alaska, the ship ventured north into so-called ten-tenths sea ice—the name shiphands give to a sea ice coating that stretches to the horizon.
The 80-meter-long Sikuliaq is not an icebreaker, but its hardened hull is rated to move through sea ice as thick as 0.8 m. And it “crunched” smoothly through ice it encountered during various trial procedures, reports chief scientist Carin Ashjian, a biological oceanographer from the Woods Hole Oceanographic Institution (WHOI) in Massachusetts. (The ship moved easily through 0.5 m-thick solid ice, but was stopped by stacked "rafting" ice that was 1.5 m thick. For images of the ship in action, see 1:53 in the video below.)
Other aspects of the $200 million ship’s facilities impressed the science crew aboard. Winches delivered sampling and sensory equipment smoothly in ice and water, and crews successfully exited the ship on foot to take samples from surrounding ice. Inside the nearly 3500-gross-ton vessel, large decks and spacious lab areas had scientists salivating. “She’s a great ship, and a great addition to the U.S. science fleet,” Ashjian says. The ship has about 24 berths for scientists, in addition to a crew of about 20, and has a range of about 30,000 kilometers.
Previously, U.S. scientists have relied on the Coast Guard’s Healy icebreaker for access to the Arctic. Now, Sikuliaq will allow scientists to access icy areas during the fall and spring “shoulder seasons” that other existing vessels generally avoid. “She opens the southern parts of the Bering Sea during those times of year,” Ashjian says.
WHOI oceanographer Sam Laney was particularly interested in the scientific possibilities that will allow. “Since people don’t get a lot of opportunities to come up here in the Bering Sea this early in the year, we don’t have a lot of data on what phytoplankton species are ‘early risers’, i.e., species that do especially well in early spring. These would be analogous to crocuses or daffodils on land: the plants that you see blooming earliest in the year,” he wrote in a blog post during the cruise.
Laney tested some new sampling equipment during a foray with other scientists off the ship and onto the ice. A few graduate students took samples that might inform their dissertations, Ashjian says. But the real science will begin in July, when Sikuliaq finally begins research operations in icy seas during a fall cruise back to the edge of the sea ice.