The Trump administration is dismantling a $368 million deep-ocean observation system that was put in place a decade ago to monitor coastal environments, marine ecosystems and powerful currents that affect the global climate.
The National Science Foundation said it would send ships in June to begin removing more than 900 deep-sea instruments anchored off Oregon, Washington State, Alaska, North Carolina, and an area between Greenland and Iceland known as the Irminger Sea.
Scientists have used data from the system to understand how the ocean is absorbing greenhouse gases from the atmosphere, how changes in ocean temperature such as marine heat waves might affect fisheries or signal bigger shifts in the climate, and coastal flooding along the East Coast.
The station in the Irminger Sea has been key to understanding changes in the Atlantic Meridional Overturning Current, a global conveyor belt of water that some scientists are concerned may be weakening as a result of climate warming. A collapse of the current could have severe weather effects.
The Irminger Sea moorings are fixed to seafloor 9,200 feet below the surface and are part of an international collaboration among scientists who are studying the overturning current.
Michael England, a spokesman for the National Science Foundation, said the decision to dismantle the network, known as the Ocean Observatories Initiative, “aligns with N.S.F.’s wider strategy to have a nimbler approach to prioritizing support for evolving scientific priorities and emerging technologies as well as a deliberate approach to smart life cycle management within its portfolio of research infrastructure.”
Craig McLean, who was the acting chief scientist at the National Oceanic and Atmospheric Administration during the first Trump term, said the move was part of a pattern in the Trump administration.
“This reflects the further lack of understanding that the current administration has of scientific value and scientific merit,” Dr. McLean said. “By dismantling such a system, we push the United States back yet again into a rear seat in global scientific leadership.”
The ocean observation system began operating in 2016 and was expected to continue for 25 years. Jim Edson, a marine meteorologist who led the Ocean Observatories Initiative, called it “the world’s most advanced continuously operating ocean observing systems.” When it was first proposed, the science foundation said it was important to have a long-term presence at scientifically important sites in the Atlantic and Pacific oceans.
Removing the instruments could take 15 months. Seismic instruments positioned around an active underwater volcano off Oregon will continue operating until 2028.
Each observation station consists of several moorings that secure long arrays of devices connected to wires. The devices measure ocean currents as well as chemical and biological conditions from the water’s surface down thousands of feet.
The instruments were hardened to resist the pressure of the deep ocean, corrosive seawater as well as marine plants and animals that can foul electronics. Remotely controlled robotic vehicles and gliders around the moorings collect and transmit data to research laboratories.
Funded by the National Science Foundation, the network was coordinated by the Woods Hole Oceanographic Institution in collaboration with Rutgers University, the University of Washington and Oregon State University. A Woods Hole spokeswoman referred questions to the N.S.F.
It cost $48 million annually to operate the network. The Trump administration repeatedly tried to shutter it, proposing to cut its funding by 80 percent in both 2025 and again in 2026. Congress pushed back, restoring the money.
To try to reduce costs, managers turned off some of the instruments and collected less data, according to a December 2025 presentation about the observatories at a the annual meeting of the American Geophysical Union, a nonprofit organization of scientists.
Still, the science foundation moved ahead to decommission the observatory network.
Hilary Palevsky, professor of earth and environmental sciences at Boston College, has been using data from the Irminger instruments for the past decade to better understand how the ocean absorbs carbon dioxide from the atmosphere.
Scientists have benefited from downloading data from remote ocean instruments, rather than making difficult, dangerous and expensive trips to sea each year. Pulling up the instruments without a plan to store them or to continue collecting data “is very hasty,” she said.
“One of the real tragedies here is that collecting data effectively at this site was a huge engineering challenge, and it’s not the kind of thing where you can just leave your notes for the next person who comes in,” Dr. Palevsky said. “There’s a lot of expertise that has the potential to be lost.”
The $48 million annual budget for the observation network was small compared with the value of the data it collected for understanding the oceans and the climate, Dr. McLean said.
The observation station off Cape Hatteras, N.C., collected data about coastal currents that influence the weather and commercial fisheries along the U.S. East Coast.
Mike Muglia, professor of coastal studies at East Carolina University, used the data to understand waves, currents and sea life for a marine renewable energy test site in Nags Head, N.C., that was funded by the Energy Department.
Moorings that stretch west off the coast of Newport, Ore., and Grays Harbor, Wash., captured temperature, acidity, and oxygen content data that is key to predicting climate-related environmental changes as well as the health of the region’s commercial fishing industry. Another station is anchored 620 miles offshore in the central Gulf of Alaska.
