More than 100 scientists and crew from more than 20 U.S. research institutions will embark for NASA’s month-long , or EXPORTS, oceanographic campaign. The 91̽»¨ is leading one of the expedition’s , with several others led by 91̽»¨School of Oceanography alumni who are now faculty members at other institutions.

A NASA event Aug. 9 in Seattle will kick off the expedition.

Two large research vessels — the R/V Revelle and R/V Sally Ride, both operated by the Scripps Institution of Oceanography at University of California, San Diego — will sail west 200 miles into the open ocean. From these seaborne laboratories, researchers will explore plankton life and the chemical and physical properties of the ocean from the surface down a half-mile to the “” — a region below the sunlit surface layer where carbon from the plankton can be sequestered, or kept out of the atmosphere, for periods ranging from decades to millennia.

“By employing two ships we’ll be able to observe complex oceanographic processes that vary both in space and time that we wouldn’t be able to capture with a single ship,” , program manager for Ocean Biology and Biogeochemistry at NASA Headquarters said in a NASA .

and , both oceanographers at the 91̽»¨Applied Physics Laboratory who also hold faculty appointments with the 91̽»¨School of Oceanography, are part of the using two robotic instruments developed at the UW. The first is a 6.5-foot-long underwater vehicle called the Seaglider that will gather measurements as deep as 1 kilometer, more than half a mile. The second is a float designed to follow the motion of water in the upper ocean that will be used to collect measurements just below the sunlit upper layer.

The 91̽»¨team will use these and other autonomous tools to track upper-ocean community structure, sinking organic matter, currents and migrating zooplankton at two measurement sites in the ocean.

“Understanding, and eventually predicting, the oceans’ role in fixing and exporting carbon to depth will require sustained, long-term measurements,” Lee said. “EXPORTS takes us a step farther down that path, by advancing the use of long-endurance robotic vehicles — profiling floats and underwater gliders — for collecting biological and biogeochemical observations.”

Seven years in the making, the 2018 campaign has been a huge undertaking, said , EXPORTS science lead from the University of California, Santa Barbara.

“The impact the EXPORTS data will have for understanding how our planet is changing will be significant,” Siegel said. “NASA’s ocean-color satellite record shows us these ecosystems are highly sensitive to climate variability. Changes in phytoplankton populations affect the marine food web, since phytoplankton are eaten by many animal species, big and small.”

The projects are being funded by NASA and the National Science Foundation. Other participating institutions include Oregon State University, Monterey Bay Aquarium Research Institute, Woods Hole Oceanographic Institution, Skidmore College, University of Rhode Island, University of North Carolina at Chapel Hill, NASA Goddard Space Flight Institute, Bowdoin College and the Virginia Institute of Marine Science.

Watch a video about the UW-developed Seaglider technology:

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For more information, contact Lee at craiglee@uw.edu or 206-685-7656. For information on EXPORTS, visit . Reporters can RSVP for the Aug. 9 before July 19.

Adapted from a NASA press release: ““

The experiment conducted in the Gulf of Mexico near the site of the Deepwater Horizon oil spill placed hundreds of drifting sensors to observe how material moves on the ocean’s surface. Rather than spread out, as current calculations would predict, many of them clumped together in a tight cluster.

The results hold promise for the cleanup of marine pollution and have wider implications for ocean science. The was published the week of Jan. 16 in the Proceedings of the National Academy of Sciences.

“To observe floating objects spread out over a region the size of a city concentrate into a region smaller than a football stadium was just amazing,” said first author , a 91̽»¨professor of oceanography. “We knew there would be some concentration, but the magnitude seen was quite stunning.”

Textbook science would predict that material in the ocean would simply diffuse — that is, move apart or flow with the currents. But recent research has begun to explore the role of oceanic fronts and vortexes, and a 2015 study showed that small-scale to hundreds of feet below the water’s surface.

The new study shows that such eddies can draw in flotsam from a wide area. If scientists could somehow observe or predict this funneling behavior, it might help to clean up oil spills or recover marine plastics and other floating debris.

“The hope is to apply this in ocean cleanup projects, but first we have to figure out how to observe or predict where these concentrations will occur,” D’Asaro said.

The research was funded by the industry-backed .

For the 2016 , co-author Tamay Özgökmen and his team at the University of Miami designed inexpensive that are built from biodegradable plastic so that hundreds can be deployed at a time. During a winter cruise, the team placed the instruments about 75 kilometers from the mouth of the Mississippi River, in an area where fresh, cold river water meets saltier, warmer and denser water from the Gulf of Mexico. The cruise deployed more than 1,000 drifters, making it the largest-ever deployment of individually-trackable ocean drifters in a single location to see how they behave as a group.

The experiment that’s the focus of this study dropped 326 drifters in a grid with 1 kilometer spacing over the course of about 16 hours. Eight days later, roughly half the drifters were contained in a circle the size of 60 meters (200 feet), an area 400 times smaller than when they began. Underwater observations show a bulge of seawater plunging down simultaneously in this location.

“It is much like the spinning vortex that forms in a bathtub: Water sinks in a small region, but water from much larger region moves toward the vortex,” D’Asaro said.

The drifters are buoyant and stayed floating on the surface. They remained clumped together for about 10 days and then slowly dispersed over the following weeks. Meanwhile the other half of the drifters simply spread out over an area of 100 kilometers, as traditional calculations would predict.

“This is probably how the vertical exchange in the ocean ultimately works,” said second author , an oceanographer at the UW’s Applied Physics Laboratory. “Even though we think about ocean mixing as a large-scale process, once we start looking closer we begin to realize that it might actually happen episodically, on very small scales, at select hotspots that flash here and there.”

The findings also have wider implications for how the ocean behaves. If mixing happens at smaller scales, and less buoyant material gets sucked down into the vortex, then finer-grained models could better capture processes such as blooms of marine plants, carbon transport and water circulation.

“There have been increasing theoretical reasons to believe that something like this should happen, and some previous measurements which supported those ideas,” D’Asaro said. “But I think this will be a landmark experiment, because it is so dramatic and easy to understand.”

The project was part of the multi-institutional , based at the University of Miami. Other co-authors are Shuyi Chen at the UW; Jody Klymak at the University of Victoria; Jeroen Molemaker, James McWilliams and Roy Barkan at the University of California, Los Angeles; Guillaume Novelli, Cédric Guigand, Angelique Haza, Brian Haus and Edward Ryan at the University of Miami; Gregg Jacobs at the Naval Research Laboratory; Helga Huntley and A.D. Kirwan Jr. at the University of Delaware; Nathan Laxague at Columbia University; Falco Judt at the National Center for Atmospheric Research; and Andrew Poje at the College of Staten Island.

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For more information, contact D’Asaro at 206-685-2982 or dasaro@uw.edu and Shcherbina at 206-897-1446 or ashcherbina@apl.washington.edu. See more from the deployment cruise.