The Cooperative Institute for Climate, Ocean, and Ecosystem Studies

By Joe Selmont, CICOES

Puget Sound is celebrated for its salmon runs, Dungeness crab harvests, and oyster farms. But beneath the surface, the Sound’s changing waters may pose a threat to this abundant ecosystem. 

Because of its geography and the way ocean currents bring in carbon-rich water from the Pacific, Puget Sound is vulnerable to ocean acidification – the chemical process by which carbon dioxide from the atmosphere enters seawater and decreases the pH level. Research shows that the Sound’s waters naturally have higher acidity than the open ocean. This means that additional CO2 can create difficult conditions for species that people in the Pacific Northwest depend on for food, income, and cultural practices.

To help communities respond, the University of Washington’s Cooperative Institute for Climate, Ocean, and Ecosystem Studies (CICOES) has announced a new project funded by the Puget Sound Partnership. The project team will build a data-based tool called Puget Sound Acidification and Impacts (PSAI). The tool will provide accessible, location-specific information on acidification across the Sound, supporting the needs of fisheries, marine resource managers, tribes, and other communities.

Having better information on acidification is more than an academic exercise. Shellfish harvesters need to know whether larvae will survive in local waters. Fisheries managers need to understand how changing chemistry might affect salmon or Dungeness crab. Tribal leaders and state officials are tasked with protecting resources that support both cultural traditions and economic stability.

This is why the PSAI research team will convene an advisory panel of marine resource users and managers. This aspect of the project builds on a long history of collaboration among scientists and community partners from across the region, as exemplified by prior and ongoing work by the Washington Ocean Acidification Center (WOAC), whose co-director Jan Newton is a collaborator on the PSAI project. 

By drawing on the expertise of people who live and work on the Puget Sound, the team aims for PSAI to meet real-world needs. 

“Engagement with local experts is critical for this project,” said Larissa Dias, a CICOES postdoctoral scholar who is helping to lead the PSAI project. “Our goal is to co-design a functional tool tailored to the needs of resource managers, the people who translate the scientific information into action. To do that, we’re tapping the expertise and perspectives of people who directly support fisheries and other management activities in the Sound. It’s great that several members of our advisory panel have partnered with WOAC in the past, so they already have experience with these sorts of collaborations.”

Panel members will use their extensive knowledge of and experience with local systems to provide guidance on what information would be most useful, what regions or species should be prioritized, and how best to present the data in a way that makes sense to non-researchers. The project team will then incorporate that feedback into the final design of PSAI. The goal is to create not just a technical tool, but a shared resource that will assist with decision-making in the region.

PSAI will draw on existing scientific data from the National Oceanic and Atmospheric Administration (NOAA) and WOAC, adapting years of ocean monitoring efforts into a user-friendly format. Data from more than 61 research cruises and 7,500 samples collected across the Salish Sea since 2008 – known as the Salish Cruise data package – will form the backbone of the tool. These samples include detailed measurements of temperature, salinity, nutrients, oxygen, and carbonate chemistry. Additional data from other sources, such as the Washington State Department of Ecology, will supplement the Salish Cruise data package.

“The Salish Cruise time series provides invaluable long-term observations on changing oceanographic conditions in the Salish Sea. Together with research on biological impacts of ocean acidification performed by the Washington Ocean Acidification Center, the data are now being used to develop decision support tools and information for managers, fishers, and others who rely on our rich marine resources,” said Simone Alin, who is a supervisory oceanographer at NOAA’s Pacific Marine Environmental Laboratory, as well as a founding research partner at WOAC and a collaborator on the PSAI project.

One challenge of assessing the impacts of ocean acidification in dynamic estuarine regions like Puget Sound is that conditions vary dramatically in both space and time, with many processes influencing the water’s chemical composition. A single cruise captures short-term snapshots of conditions at sampling stations, but models and other data analysis approaches can help fill in gaps. 

To that end, the project team will apply a combination of machine learning and interpolation techniques to develop algorithms that provide accurate and timely acidity estimates for locations across Puget Sound. In other words, the researchers will build a simple yet robust artificial intelligence tool using proven methods that allow computers to recognize patterns in the data that would be nearly impossible for a human to detect, such as subtle relationships among temperature, salinity, and acidity.

“Machine learning has emerged in recent years as an effective tool in oceanography, especially for filling gaps in scattered datasets of carbonate chemistry parameters that relate to ocean acidification,” said Jonathan Sharp, a research scientist at CICOES and the leader of the PSAI project. “As an example, some recent work I led involves the use of machine learning models to quantify the progression of ocean acidification indicators in large marine ecosystems in the U.S. We found significant changes to indicators like pH and calcium carbonate saturation state, but also significant variability across space and time.”

The end result of the PSAI project will be a user-friendly interface where managers and the public can input a location, depth, and date to see estimates of acidity and related values, along with information about uncertainty. This means that users will have a way to generate on-demand, localized insights into ocean conditions, even when there are no research vessels cruising the Sound.

The project officially begins in December 2025 and will continue through May 2027. In its final phase, following the development of PSAI, the project team will host a series of workshops to introduce the tool to potential users and train them on how to apply it. Eventually, PSAI could also help validate existing ocean models, support long-term planning, and guide targeted mitigation efforts in the future.

When all is said and done, the tool will have two versions: one designed for managers and the public, and another with more detailed options for researchers.

“Local resource managers need accessible information on how acidification might affect the Sound,” Dias said. “PSAI will help provide this information, and in a way that is guided by the local managers’ needs. Ultimately, we want this tool to be useful. The science has to be accessible to the people who need it.”

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The Puget Sound Acidification and Impacts team consists of researchers from the University of Washington and NOAA, including lead principal investigator Jonathan Sharp (UW CICOES), researcher Larissa Dias (UW CICOES), collaborator Simone Alin (NOAA PMEL), collaborator Jan Newton (UW WOAC), and collaborator Brendan Carter (UW CICOES). 

The PSAI advisory panel currently consists of Aaron Dufault (Washington Department of Fish and Wildlife), Mike McHugh (Tulalip Tribes Natural Resources), and Andy Surbhier (Pacific Shellfish Institute). Additional members are anticipated to participate. 

The PSAI project is supported by funding from the Puget Sound Partnership, the Washington state agency leading the region’s collective effort to restore and protect Puget Sound.

By Wali Rana, Alaska Public Media

A specialized plane, camera and a crew of four are in Alaska to understand the ecosystems of the Bering and Chukchi seas.

Jiaxu Zhang is a research scientist at the University of Washington, and for the last four summers she’s brought a team of researchers to Nome for the Arctic Airborne Investigations and Research project, or Arctic AIR for short.

“Arctic AIR does all sorts of research, ranging from physical oceanography to sea ice surveys to phytoplankton studies and remote sensing,” Zhang said. “And sometimes we also onboard some observers to do some marine mammal surveys.”

…

By Theo Stein, NOAA Research

Carefully enhanced wastewater could one day benefit coastal marine resources

The continual rise of carbon dioxide in the atmosphere isn’t just changing weather patterns, it’s also silently altering the chemistry of the global ocean. As CO₂ dissolves into seawater, it forms carbonic acid, driving down ocean pH in a process known as ocean acidification. This fundamental shift threatens marine economies,  ecosystems, and organisms from shellfish to coral reefs.

One potential approach for reducing the local effects of ocean acidification is called ocean alkalinity enhancement, which involves shifting the chemistry of ocean water back toward its natural, slightly alkaline (basic) state. Over the past two years, a small-scale research project in Sequim, Washington has explored whether a new electrochemical process could make seawater locally less acidic while enabling it to absorb more carbon dioxide from the atmosphere. The project is part of NOAA’s larger exploration of  emerging ocean carbon management technologies, which it is pursuing at the direction of Congress.

The findings of the research team, which included scientists from NOAA’s Pacific Marine Environmental Laboratory and the University of Washington, the Department of Energy’s Pacific Northwest National Laboratory (PNNL), and the company Ebb Carbon, were published in the journal Frontiers in Environmental Engineering.

“Our project was about implementing the method in a highly-controlled, contained, modeled, and monitored environment,” said Brendan Carter, a scientist with the NOAA-University of Washington Cooperative Institute for Climate, Ocean, and Ecosystem Studies. “Our two federal labs and Ebb Carbon teamed up to ensure that this process was safe and had the expected impacts on the chemistry of seawater when operated on small scales.”

The three-year project involved pumping small amounts of seawater from Washington’s Sequim Bay into PNNL’s Marine and Coastal Research Laboratory. The seawater then entered Ebb’s prototype bipolar membrane electrodialysis system, which passed it through a series of electrically-charged membranes that split seawater into alkaline and acidic streams.

The treated alkaline seawater was held in open-air tanks while scientists measured the partial pressure of carbon dioxide dissolved in the seawater, pH, turbidity, dissolved oxygen, total dissolved inorganic carbon, and total alkalinity. The treated seawater was returned to the ocean through PNNL’s existing wastewater system in accordance with existing permits.

The researchers conducted two experiments, one in November 2024 and the second in February 2025. Their primary objectives were to assess their ability to maintain and monitor the elevated pH (less acidic) within the facility, ensuring it remained below the permitted maximum at the end of the pipe, and to determine if the increased alkalinity could be detected beyond the outfall.

In the November trial, about 7,000 gallons of alkalinity-enhanced seawater was released, roughly the volume carried by a large tanker truck. The February trial involved releasing 47,000 gallons of alkalinity-enhanced seawater —  a nearly seven-fold increase in the volume of discharged seawater compared to the November pilot. (For comparison, an Olympic swimming pool holds 660,000 gallons.) Still, the team observed no detectable alterations to the surrounding water’s temperature, salinity, turbidity, or oxygen levels, indicating a minimal immediate environmental impact. They did observe a very localized increase in alkalinity and pH that dissipated within approximately eight feet of the discharge pipe. This rapid dilution highlighted the challenges of detecting small-scale ocean alkalinity enhancement signals in dynamic coastal environments.

This study demonstrates that a conservative small-scale release of electrochemically generated alkalinity-enhanced seawater from a coastal outfall can meet existing environmental permits, and temporarily improve water quality.

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For more information, contact Theo Stein, NOAA Communications: theo.stein@noaa.gov

By Evan Bush, NBC News

The magnitude-8.8 earthquake off Russia’s Kamchatka peninsula sent a wave of water racing at the speed of a jetliner toward Hawaii, California and Washington state, spurring warnings and alarm overnight Wednesday.

But when the tsunami waves arrived, they didn’t cause devastation or deaths in the United States, and the inundation might not have appeared threatening in some locations where warnings were issued.

That doesn’t mean the tsunami was a “bust,” that it was poorly forecast or that it didn’t pose a risk, earthquake and tsunami researchers said.

“You start to hear ‘tsunami warning,’ and everyone immediately thinks of the last Hollywood movie they saw, and then it comes in at 3 feet and people are like, ‘What’s that?’” said Harold Tobin, the director of the Pacific Northwest Seismic Network and a professor at the University of Washington. “We should count it as a win that a tsunami occurred, we got a warning and it wasn’t the worst-case scenario.”

Here’s what to know.

How strong was the Kamchatka earthquake? And why did it change so much?

Initial reports from the U.S. Geological Survey pegged the Kamchatka earthquake at magnitude 8.0. Later, it was upgraded to 8.8.

“That is not uncommon for very, very large earthquakes in those initial minutes,” Tobin said. “Our standard algorithms for determining the size of an earthquake quickly saturate. It’s like turning up an amp and getting a lot of distortion.”

One of the first signs the earthquake was stronger than the initial seismic reports said was an initial measurement from a buoy about 275 miles southeast of the Kamchatka peninsula.

The buoy, which is part of the National Oceanographic and Atmospheric Administration’s DART (Deep-ocean Assessment and Reporting of Tsunamis) system, is connected to a seafloor pressure sensor about 4 miles below the surface.

The sensor registered a 90-centimeter wave — more than 35 inches — which is eye-popping to tsunami researchers.

“That’s the second-largest recording we ever saw in the tsunami world,” said Vasily Titov, a senior tsunami modeler at NOAA’s Pacific Marine Environmental Laboratory, adding that it indicated there was “a catastrophic tsunami propagating in the ocean.”

Titov said the only higher reading was from the 2011 Tōhoku earthquake and tsunami, which killed nearly 16,000 people in Japan.

Seismic models later confirmed that Wednesday’s earthquake was magnitude 8.8, which means it released nearly 16 times as much energy as a magnitude-8.0 earthquake, according to a USGS calculation tool.

Tōhoku was much bigger.

Tobin estimated that earthquake released two to three times as much energy as was observed in Kamchatka. Titov said the tsunami in Japan was also about three times larger.

In addition, he said the Tōhoku earthquake “produced an anomalously large seafloor displacement,” lurching and moving more water than expected, even for an earthquake of its magnitude.

At Kamchatka, “it’s likely that there was less seafloor displacement than could have happened in a worst-case or more dire scenario for a magnitude-8.8,” Tobin said, though more research will be needed to confirm that theory.

[…]

Why were people in Hawaii evacuated for a 5-foot wave?

Yong Wei, a tsunami modeler and senior research scientist at the University of Washington and the NOAA Center for Tsunami Research, said a 1.5-meter (5-foot) tsunami wave can be very dangerous, particularly in shallow waters off Hawaii.

Tsunami waves contain far more energy than wind waves, which are far shorter in wavelength and period (time between waves) and slower in speed.

Wei said tsunami waves of the size that struck Hawaii can surge inland “tens of meters,” produce dangerous currents and damage boats and other moveable objects.

“People die. If they stay there and they don’t get any warning, 2 meters can definitely kill people,” Wei said. “If you’re on the beach, strong currents can definitely pull you out into the ocean and people will get drowned.”

Tobin said the initial warnings were conservative but appropriate, in his view.

“I don’t want people to think, oh, we had a warning and nothing much happened and pooh-pooh it — ‘I can ignore it,’” he said. “Warnings by nature have to err a bit on the side of caution.”

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Read more about CICOES research on tsunami forecasts and modeling.

By Monica Allen, NOAA

Ice forecasts would boost public safety, subsistence fishing, hunting, transportation and commerce

NOAA and the University of Washington have joined with the Native Village of Kotzebue, Alaska, to create a new forecast model that will help predict the spring ice breakup on a major lake outside the village.

Hotham Inlet, known locally as Kobuk Lake, is a 38-mile-long, 19-mile-wide lake that transforms each fall when the ice freezes into a prime place for fishing and a critical travel corridor for people on snowmachines and with dog teams.

The lake is a few miles from Kotzebue, the largest community and the economic and transportation hub in Alaska’s Northwest Arctic Borough. The iced-over lake allows local communities to create an ice road to transport air freight that arrives in Kotzebue to communities around the lake, visit friends and make it easier for people from smaller villages to get to Kotzebue for shopping.

While NOAA National Weather Service ice forecasts provide information about ocean and coastal sea ice and ice breakups on major rivers, there are no specialized forecast models for Alaskan lakes, even large ones like Kobuk Lake, which is fed by two rivers and influenced by tidal flow from the Chukchi Sea.

“This new model we are developing is the future of ice prediction,” said Jiaxu Zhang, the project leader who is a research scientist at the UW’s Cooperative Institute for Climate, Ocean and Ecosystem Studies and NOAA’s Pacific Marine Environmental Laboratory in Seattle. “We want to make it useful and relevant to the people who depend on knowing the condition of ice for safe fishing, hunting, transportation and trade. And the best way to do that is to work directly with the people of Kotzebue on it.”

Unlike traditional ice models that treat ice as one continuous sheet, this new model will simulate how individual ice floes crack, move and pile up — complex processes that are key to predicting exactly when and where Kobuk Lake ice will break up.

For thousands of years, the community has used its Indigenous knowledge and deep understanding of ice to plan their fishing and hunting. But with changing temperatures and weather, this new model which combines physical science with Indigenous knowledge could improve the forecasting of spring breakup for Kotzebue and become a model for other Alaskan and Arctic locations.

The residents of Kotzebue bring valuable knowledge of the ice, the wildlife that inhabit it and the ways they have detected when the breakup is occurring in the past.

Ice fishing provides major source of protein for locals

“Fishing here is really important for us,” said Bobby Schaeffer, an elder from Kotzebue who contributes to the project. For Schaeffer and many of his neighbors, much of their protein comes from subsistence fishing and hunting.

Kobuk Lake is well known for a large whitefish called sheefish that can grow as large as 50 pounds. Community members also fish for herring and a variety of smaller whitefish species. These fish are then frozen, pickled or dried to be consumed throughout the year.

The ice fishing season typically begins in late fall and continues into May. In recent years, the ice in parts of the lake has broken up earlier than it did 20 or more years ago, said Schaeffer. He attributes it to the warming atmosphere, which is affecting not only the ice formation and thickness, but all the fish migration patterns, birds, seals and caribou that depend on the lake’s ecosystem.

Team gathers aerial and on-ice observations for model

To create the model, Zhang and her interdisciplinary team collected observations of the ice before and during breakup, including aerial surveys from a NOAA Twin Otter airplane operated by NOAA Commissioned Corps officers and crew. In May, the aircraft was loaded with sensors to take high-resolution images and LIDAR (Light Detection And Ranging), a remote-sensing method that uses laser light to measure distances and create highly detailed 3D representations of ice thickness, surface roughness, and environmental features.

In addition to the aerial observations, Schaeffer and Alex Whiting, the Native Village of Kotzebue environmental program director, collected observations on the ground and on the ice. Schaeffer measured the thickness of the ice over time by drilling holes in strategic locations on the ice. Tyler Kramer, a Kotzebue high school student, monitored the salinity of the water flowing into the lake from the Chukchi Sea. By understanding how much salt water flows into the lake and how much of the colder fresh water from rivers blocks that salt water flow into the lake, the scientists have key information for the model about how the warmer saltier water accelerates ice melting from below.

The Kotzebue community members have also contributed a wealth of information about how the breakup has occurred in past years, areas where it is likely to soften first and areas where ice may support fishing and hunting longer into the spring before it breaks up.

Two interesting focal points of the research are the formation of annual pressure ridges running across the lake and recurring thin ice areas that melt out early in the breakup process.  While the location of these open water areas reappear in the same place each year, the position of the associated cracks can change from year to year, according to an analysis of satellite images and the current observations. Understanding the forces that cause these phenomena will help to create a successful and accurate breakup model.

The next step to building a model is to create what’s called a hindcast, a validation technique that involves running historical observations through the model and comparing the accuracy of the output to the actual timing of past ice breakups. From this, the team will create and test a model to predict future ice breakup.

By Lauren Kirschman, UW News

The Atlantic Meridional Overturning Circulation, or AMOC, is a system of ocean currents that plays a crucial role in regulating Earth’s climate by transporting heat from the Southern to Northern Hemisphere. Confined to the Atlantic basin, the AMOC modulates regional weather — from mild summers in Europe to monsoon seasons in Africa and India.

Climate models have long predicted that global warming will cause the AMOC to weaken, with some projecting what amounts to a near-collapse relative to the AMOC strength in observations today. But a new study from a team of researchers that included the University of Washington shows that the AMOC is likely to weaken to a much lesser extent than current projections suggest. The study was published May 29 in Nature Geoscience.

A severe weakening would have far-reaching consequences, including changes in regional sea level rise, and major shifts in regional climate, such as colder conditions in northern Europe and drier weather in parts of the Amazon and West Africa.

“Our results imply that, rather than a substantial decline, the AMOC is more likely to experience a limited decline over the 21^st century — still some weakening, but less drastic than previous projections suggest,” says David Bonan, lead author of the study and a UW postdoctoral research fellow in the Cooperative Institute for Climate, Ocean and Ecosystem Studies.

The researchers developed a simplified physical model based on fundamental principles of ocean circulation — specifically, how sea water density differences and the depth of the overturning circulation are related — that also incorporates real-world measurements of the ocean current’s strength. The real-world data was collected over 20 years with monitoring arrays and other observations of the Atlantic basin.

Results show that the AMOC will weaken by around 18-43% by the end of the 21^st century. While this represents some weakening, it’s not the near-collapse that more extreme climate model projections suggest.

By Joe Selmont, CICOES

Each year, the ocean and atmosphere exchange billions of tons of carbon dioxide (CO₂). This process is one of the planet’s most powerful natural balancing acts — and it’s not happening uniformly over time or across the world. 

In a new international study including researchers from the University of Washington and NOAA, a team of scientists has shown that the Pacific Ocean is taking up more CO₂ than ever before, and that this uptake is increasing over time.

The study is part of a larger effort called RECCAP2, an international collaboration coordinated through the Global Carbon Project. One of RECCAP2’s goals is to “take stock” of carbon in the ocean. This is an ambitious task that requires synchronizing observations, models, and expertise from many countries. 

For the Pacific Ocean, this meant assembling decades of measurements and modeling results to understand not just how much carbon the Pacific absorbs, but how that uptake is changing over space and time. According to the study, between 1985 and 2018, the Pacific absorbed, on average, about 2.6 billion tons more carbon per year than it did in pre-industrial times. And the annual rate of uptake has been growing steadily each decade — by about 0.1 billion tons per year.

“This is a comprehensive synthesis of a lot of collaborative research on the Pacific Ocean over the last several decades,” said Brendan Carter, an oceanographer at the UW’s Cooperative Institute for Climate, Ocean, and Ecosystem Studies. “Across the world, scientists are taking on the challenging task of tracking ocean carbon dioxide uptake from a lot of different angles.”

Carter worked alongside Richard Feely, a senior scientist at NOAA’s Pacific Marine Environmental Laboratory, and other collaborators from the U.S., Europe, and Japan. Together, they compared results derived from several methods: observational data from research cruises, autonomous vehicles, and moored sensors, as well as outputs from many different models — sophisticated simulations that aim to represent ocean physics and chemistry from first principles.

Both approaches have strengths and limitations. 

Observational data and estimates, Carter explained, are grounded in the real world and require fewer assumptions. But the vast majority of the ocean is not being measured at any given time, so estimation techniques are still needed to fill in the gaps. 

Models, on the other hand, can simulate every part of the ocean at every moment — including future conditions. In theory, this eliminates blind spots. In practice, however, a model’s accuracy depends on the assumptions it is built upon. And while those assumptions are grounded in historical data, the ocean and atmosphere form an especially complex system, inevitably introducing some unpredictability. 

This underscores why the research team used a wide variety of methods.

Carter said, “By using both observations and models — and multiple kinds of models — we can compare results and learn where our approaches agree, and where the uncertainties still lie.”

One key finding from this comparison is that despite occasional differences, the methods tended to converge upon similar results in many regions. That gives researchers growing confidence in their estimates, and allows them to track trends over time.

And in the Pacific, the trend is clear: CO₂ uptake is increasing. But Carter, Feely, and the rest of their team wanted to determine what is driving this increase. 

“The southern Pacific is one of the largest CO₂ sinks on Earth,” said Feely. “But we also see a huge amount of variability across the Pacific — especially in the equatorial Pacific, which is strongly affected by El Niño events.”

During El Niño years, warm water spreads across the equator, reducing upwelling — the process by which deep, carbon-rich and nutrient-rich water rises to the surface. Once at the surface, this upwelled water exchanges carbon with the atmosphere, often for the first time in decades or centuries. It releases old “natural” carbon accumulated by the decomposition of plants and animals over the years, but also picks up some of the carbon that humans have added to the atmosphere over that same timespan. However, the upwelled nutrients support the growth of marine life near the surface, which enables the ocean to take back some of the natural carbon.

“That dance of carbon — the interplay between natural and anthropogenic sources, upwelling, and biology — that is what we’re trying to understand and quantify,” Carter said.

Despite year-to-year and regional variability, the team’s analysis shows a consistent increase in CO₂ uptake across the Pacific over recent decades. In one sense, that’s good news: the ocean continues to perform a vital role in moderating the amount of carbon in the atmosphere. 

But Carter and Feely also expressed caution. There are concerns related to ocean acidification: as more carbon enters the ocean, it initiates a series of chemical reactions that increase acidity. This may have consequences for all kinds of marine life and ecosystems — and the humans who rely upon them. Plus, chemical principles suggest that as more CO₂ is absorbed, the ocean’s ability to take up additional carbon may eventually slow down.

“We’re trying to get the best data we can,” said Carter. “That way, the methods we use to project future scenarios will be as accurate as possible.”

This research reinforces the necessity of both global collaboration and methodological diversity. The strength of the conclusions, Carter emphasized, come not from one model or one dataset, but from combining many.

“By having so many groups, each with their own tools and expertise, we’re able to create a fuller picture,” he said. “With big questions like this, it’s important that we work together.” 

Read the full study in Global Biogeochemical Cycles.