Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Research Regions

Pacific Islands

The Pacific Islands are greatly affected by worldwide ocean changes threatening important coral reefs, species and fisheries that are vital for the economy and culture. Researchers study the direct and indirect effects of ocean acidification to develop ways to manage the impacts on the environment and communities.

View All Regions

Monitoring OA alongside the health of coral reefs and other marine species

The Pacific Islands region covers a vast area and includes the Exclusive Economic Zones surrounding the State of Hawaiʻi, the Territories of American Samoa and Guam, the Commonwealth of the Northern Marianas Islands, and the U.S. Pacific Remote Island Areas. While much of the region is uninhabited and federally protected, it is home to biologically-diverse coral reef ecosystems and a number of threatened or endangered species. It also supports culturally and economically valuable commercial, subsistence and recreational fisheries. These ecosystems generally experience relatively low levels of local anthropogenic stress. However, global forcing including basin-wide climate variability such as the El Niño Southern Oscillation and the Pacific Decadal Oscillation, and global change significantly impacts this region.

Underwater scene of cheveroned butterflyfish and corals
View FULL Research Plan (PDF)

Tracking progress of ocean acidification research in the Pacific Islands

Map of North America highlighting the Pacific Islands Region
The Pacific Islands Region includes the Exclusive Economic Zones surrounding the State of Hawai'i, the Territories of American Samoa and Guam, the Commonwealth of the Northern Marianas Islands and the U.S. Pacific Remote Island Areas.

The research goals in the Pacific Islands Region are to:

  • Maintain existing and develop new ocean acidification monitoring sites co-located with biological surveys of coral reef and broader marine ecosystems to improve understanding of ocean acidification progression and response to be used in real-time forecasts for risk assessment and decision making
  • Integrate physical, chemical, biological, and ecological data to assess ecosystem-wide direct and indirect impacts of ocean acidification, with an emphasis on key Pacific marine species
  • Couple environmental, ecological, human-use, and non-use valuation models to assess ocean acidification impacts to human well-being and develop effective ecosystem-based management strategies and relevant science communication tools.

The following charts represent the mid-point progress in implementing research actions that focus on the Pacific Islands Region according to the NOAA Ocean, Coastal, and Great Lakes Acidification Research Plan.

NOAA invests in research and activities toward meeting goals that improve our ability to understand and predict environmental change, species and ecosystem to response to changing ocean chemistry, and the human impacts of these changes. The report card below summarizes progress over the past five years toward meeting these goals for the Pacific Islands Region, measured by the number of major actions toward meeting this goal: good progress (4+ actions), some progress (1-3 actions) and no known progress.

Good overall progress

Some progress

No known progress

Environmental Change

There are eight environmental change actions: three have good overall progress, four have made some progress and one has no known progress.

Biological Sensisitivity

There are eight biological sensitivity actions: one has good overall progress, four have made some progress and three have no known progress.

Human Dimensions

There are six human dimension actions: five have made some progress and one has no known progress.

Featured Research Projects

Environmental Change
Long-term Assessment of Ocean Acidification and Coral Reef Health
View Project
Biological Sensitivity
Assessing Alkalinity Enhancement on Coral Reef Calcifiers
View Project
Human Dimensions
Aquaculture Research and Outreach Assessing Ocean Acidification Mitigation
View Project

OAP Funded Projects

A large coral in American Samoa known as "Big Momma" Credit: NOAA Fisheries
Fatoata: Sami a Taeao (Tomorrow’s Ocean)
  • PI(s): Vera Peck, Fatoata
  • Fiscal Year Funded: 2024, 2025, 2026
  • Grant Award # NA25OARX017G0001-T1-01
This project provides new ocean acidification education to communities in American Samoa...
Project Summary >
The colder water assemblage of foraminifera. T. quinqueloba, N. incompta and G. falconensis are common. Credit: NOAA Fisheries
Determining the Influence of Ocean Alkalinity Enhancement on Foraminifera Calcification, Distribution, and Calcium carbonate Production
  • PI(s): Laura Haynes
  • Fiscal Year Funded: 2023, 2024, 2025, 2026
  • Grant Award # NA23OAR0170513
This project examines the effects of different materials used in ocean alkalinity enhancement on foraminifera...
Project Summary >
Coral Reef off the coast of Coconut Island in Kāneʻohe. Photo by Keisha Bahr
Assessing the effects and risks of ocean alkalinity enhancement on the physiology, functionality, calcification, and mineralogy of corals and crustose coralline algae in the Pacific
  • PI(s): Melissa Meléndez
  • Fiscal Year Funded: 2023, 2024, 2025, 2026
  • Grant Award # NA23OAR0170507
This project will identify how corals and crustose coralline algae respond to immediate alkalinity additions and to determine the effects of chronic and acute exposure to ocean alkalinity enhancement...
Project Summary >
View More Projects

Latest Publications

Estimating coral reef carbonate budgets using Structure‑from‑Motion photogrammetry
Citation: Barkley, H.C., Halperin, A.A., Torres-Pulliza, D. et al. Estimating coral reef carbonate budgets using Structure-from-Motion photogrammetry. Coral Reefs 44, 937–951 (2025). https://doi.org/10.1007/s00338-025-02660-7
Read Summary >
Biological Responses to Ocean Acidification Are Changing the Global Ocean Carbon Cycle
  • R. C. Barrett, B. R. Carter, A. J. Fassbender, B. Tilbrook, R. J. Woosley, K. Azetsu-Scott, R. A. Feely, C. Goyet, M. Ishii, A. Murata, F. F. Pérez
  • Global Biogeochemical Cycles
  • March 24, 2025
Citation: Barrett, R. C., Carter, B. R., Fassbender, A. J., Tilbrook, B., Woosley, R. J., Azetsu-Scott, K., Feely, R. A., Goyet, C., Ishii, M., Murata, A., & Pérez, F. F. (2025). Biological Responses to Ocean Acidification Are Changing the Global Ocean Carbon Cycle. Global Biogeochemical Cycles. https://doi.org/10.1029/2024GB008358
Read Summary >
Global Carbon Budget 2024
  • Pierre Friedlingstein, Michael O'Sullivan, Matthew W. Jones, Robbie M. Andrew, Judith Hauck, Peter Landschützer, Corinne Le Quéré, Hongmei Li, Ingrid T. Luijkx, Are Olsen, Glen P. Peters, Wouter Peters, Julia Pongratz, Clemens Schwingshackl, Stephen Sitch, Josep G. Canadell, Philippe Ciais, Robert B. Jackson, Simone R. Alin, Almut Arneth, Vivek Arora, Nicholas R. Bates, Meike Becker, Nicolas Bellouin, Carla F. Berghoff, Henry C. Bittig, Laurent Bopp, Patricia Cadule, Katie Campbell, Matthew A. Chamberlain, Naveen Chandra, Frédéric Chevallier, Louise P. Chini, Thomas Colligan, Jeanne Decayeux, Laique M. Djeutchouang, Xinyu Dou, Carolina Duran Rojas, Kazutaka Enyo, Wiley Evans, Amanda R. Fay, Richard A. Feely, Daniel J. Ford, Adrianna Foster, Thomas Gasser, Marion Gehlen, Thanos Gkritzalis, Giacomo Grassi, Luke Gregor, Nicolas Gruber, Özgür Gürses, Ian Harris, Matthew Hefner, Jens Heinke, George C. Hurtt, Yosuke Iida, Tatiana Ilyina, Andrew R. Jacobson, Atul K. Jain, Tereza Jarníková, Annika Jersild, Fei Jiang, Zhe Jin, Etsushi Kato, Ralph F. Keeling, Kees Klein Goldewijk, Jürgen Knauer, Jan Ivar Korsbakken, Xin Lan, Siv K. Lauvset, Nathalie Lefèvre, Zhu Liu, Junjie Liu, Lei Ma, Shamil Maksyutov, Gregg Marland, Nicolas Mayot, Patrick C. McGuire, Nicolas Metzl, Natalie M. Monacci, Eric J. Morgan, Shin-Ichiro Nakaoka, Craig Neill, Yosuke Niwa, Tobias Nützel, Lea Olivier, Tsuneo Ono, Paul I. Palmer, Denis Pierrot, Zhangcai Qin, Laure Resplandy, Alizée Roobaert, Thais M. Rosan, Christian Rödenbeck, Jörg Schwinger, T. Luke Smallman, Stephen M. Smith, Reinel Sospedra-Alfonso, Tobias Steinhoff, Qing Sun, Adrienne J. Sutton, Roland Séférian, Shintaro Takao, Hiroaki Tatebe, Hanqin Tian, Bronte Tilbrook, Olivier Torres, Etienne Tourigny, Hiroyuki Tsujino, Francesco Tubiello, Guido van der Werf, Rik Wanninkhof, Xuhui Wang, Dongxu Yang, Xiaojuan Yang, Zhen Yu, Wenping Yuan, Xu Yue, Sönke Zaehle, Ning Zeng, and Jiye Zeng
  • Earth System Science Data
  • March 14, 2025
Citation: Friedlingstein, P., O’Sullivan, M., Jones, M. W., Andrew, R. M., Hauck, J., Landschützer, P., Le Quéré, C., Li, H., Luijkx, I. T., Olsen, A., Peters, G. P., Peters, W., Pongratz, J., Schwingshackl, C., Sitch, S., Canadell, J. G., Ciais, P., Jackson, R. B., Alin, S. R., Arneth, A., Arora, V., Bates, N. R., Becker, M., Bellouin, N., Berghoff, C. F., Bittig, H. C., Bopp, L., Cadule, P., Campbell, K., Chamberlain, M. A., Chandra, N., Chevallier, F., Chini, L. P., Colligan, T., Decayeux, J., Djeutchouang, L. M., Dou, X., Duran Rojas, C., Enyo, K., Evans, W., Fay, A. R., Feely, R. A., Ford, D. J., Foster, A., Gasser, T., Gehlen, M., Gkritzalis, T., Grassi, G., Gregor, L., Gruber, N., Gürses, Ö., Harris, I., Hefner, M., Heinke, J., Hurtt, G. C., Iida, Y., Ilyina, T., Jacobson, A. R., Jain, A. K., Jarníková, T., Jersild, A., Jiang, F., Jin, Z., Kato, E., Keeling, R. F., Klein Goldewijk, K., Knauer, J., Korsbakken, J. I., Lan, X., Lauvset, S. K., Lefèvre, N., Liu, Z., Liu, J., Ma, L., Maksyutov, S., Marland, G., Mayot, N., McGuire, P. C., Metzl, N., Monacci, N. M., Morgan, E. J., Nakaoka, S.-I., Neill, C., Niwa, Y., Nützel, T., Olivier, L., Ono, T., Palmer, P. I., Pierrot, D., Qin, Z., Resplandy, L., Roobaert, A., Rosan, T. M., Rödenbeck, C., Schwinger, J., Smallman, T. L., Smith, S. M., Sospedra-Alfonso, R., Steinhoff, T., Sun, Q., Sutton, A. J., Séférian, R., Takao, S., Tatebe, H., Tian, H., Tilbrook, B., Torres, O., Tourigny, E., Tsujino, H., Tubiello, F., van der Werf, G., Wanninkhof, R., Wang, X., Yang, D., Yang, X., Yu, Z., Yuan, W., Yue, X., Zaehle, S., Zeng, N., and Zeng, J.: Global Carbon Budget 2024, Earth Syst. Sci. Data, 17, 965–1039, https://doi.org/10.5194/essd-17-965-2025, 2025.
Read Summary >
View More Publications

Get involved with ocean acidification

The NOAA Ocean Acidification Program exists to meet the ocean acidification research and monitoring needs of the U.S. See how you can get involved to serve your community and participate in cutting-edge research and education and outreach. 

Get involved

Long-term assessment of ocean acidification and coral reef health

Colorful coral reef with different types of corals and fish.
Credit: Julie Bedford, NOAA

The Office for Coastal Management’s National Coral Reef Monitoring Program (NCRMP) provides consistent, sustained and long-term measurement of key indicators that gauge the status and trends of U.S. coral reef health. In the Pacific Islands, monitoring of climate change and ocean acidification indicators is led by the Pacific Islands Fisheries Science Center and supported by the Ocean Acidification Program. NCRMP monitoring in the region consists of diel carbonate chemistry sampling at fixed sites and discrete carbonate chemistry sampling at fixed and random sites. NCRMP also conducts ocean acidification ecological response monitoring, which include coral growth and calcification, net carbonate accretion and bioerosion rates. Coral reefs provide many ecosystem services like protection from storms and sea level rise and support fisheries and tourism that help safeguard coastal communities and economies.

Assessing alkalinity enhancement on coral reef calcifiers

Landscape view of coral reef on coconut island
Image credit: K. Bahr

Coral reefs are important ecosystems for marine biodiversity and human communities that can be impacted by ocean acidification. In a project supported through the National Oceanographic Partnership Program with funding from the Department of Energy, scientists are investigating how ocean alkalinity enhancement may help counteract the effects of ocean acidification. The goal of the research is to understand how Pacific tropical and subtropical corals and crustose coralline algae respond to immediate alkalinity additions and to determine the effects of chronic and acute exposure to ocean alkalinity enhancement. Laboratory and mesocosm experiments will test the mechanisms of calcification under different scenarios, with the goal of informing future coral restoration and ocean alkalinity enhancement activities.

More about this work

Aquaculture Research and Outreach Assessing Ocean Acidification Mitigation

An arrangement of bivalve shells
Image credit: Maria Haws

The Hilo Bay Research and Training Farm was established in 2011 by researchers to develop shellfish farming in collaboration with non-profit, educational and private sector partners to enhance community benefits. A new project is undertaking research, training and demonstration activities to develop a feasible model for a near-shore integrated multi-trophic aquaculture system that tests the use of four bivalves and limu (native seaweed) for water quality improvement, including ocean acidification mitigation. The project will focus on outreach on key coastal issues, such as water quality and sustainable economic development, and the results will be widely disseminated to interested groups and people throughout Hawai‘i.

More about this work supported by Hawai’i Sea Grant

Bioeconomic modeling to inform Alaska fisheries management

Fishing Dock in Juneau Alaska
Image credit: Allen Shimada, NOAA NMFS

Bioeconomic models are a multidisciplinary tool that use oceanography, fisheries science and social science to assess socioeconomic impacts. Funded by the Ocean Acidification Program, researchers at the Alaska Fisheries Science Center use a bioeconomic model to study the impacts of ocean acidification on Eastern Bering Sea crab, northern rock sole and Alaska cod. The goal is to predict how ocean acidification will affect abundance yields and income generated by the fisheries. This work informs the potential economic impacts of ocean acidification and future decision making and research planning.

More about this work

Effects of ocean acidification and temperature on Alaskan crabs

Red King Crab
Image credit: David Csepp, NMFS AKFSC ABL

Long-term declines of red king crab in Bristol Bay, Alaska may be partially attributed to ocean acidification conditions. These impacts may be partially responsible for the fishery closures during the 2021–2022 and 2022–2023 seasons. Researchers found that ocean acidification negatively impacts Alaskan crabs generally by changing physiological processes, decreasing growth, increasing death rates and reducing shell thickness. Funded by the Ocean Acidification Program, scientists at the Alaska Fisheries Science Center continue to investigate the responses of early life history stages and study the potential of various Alaska crabs to acclimate to changing conditions. Results will inform models that will use the parameters studied to predict the effects of future ocean acidification on the populations of red king crab in Bristol Bay as well as on the fisheries that depend on them. Fishery managers will better be able to anticipate and manage stocks if changing ocean chemistry affects stock productivity and thus the maximum sustainable yield.

More about this work

Forecasts for Alaska Fisheries

Crab pots and fishing nets in Alaska's Dutch Harbor
Image credit: Michael Theberge

Understanding seasonal changes in ocean acidification in Alaskan waters and the potential impacts to the multi-billion-dollar fishery sector is a main priority. Through work funded by NOAA’s Ocean Acidification Program, the Pacific Marine Environmental Laboratory developed a model capable of depicting past ocean chemistry conditions for the Bering Sea and is now testing the ability of this model to forecast future conditions. This model is being used to develop an ocean acidification indicator provided to fisheries managers in the annual NOAA Eastern Bering Sea Ecosystem Status Report.

ADAPTING TO OCEAN ACIDIFICATION

The NOAA Ocean Acidification Program (OAP) works to prepare society to adapt to the consequences of ocean acidification and conserve marine ecosystems as acidification occurs. Learn more about the human connections and adaptation strategies from these efforts.

Adaptation approaches fostered by the OAP include:

FORECASTING

Using models and research to understand the sensitivity of organisms and ecosystems to ocean acidification to make predictions about the future, allowing communities and industries to prepare

Closeup of oysters cupped in someone's hands

MANAGEMENT

Using these models and predictions as tools to facilitate management strategies that will protect marine resources and communities from future changes

TECHNOLOGY DEVELOPMENT

Developing innovative tools to help monitor ocean acidification and mitigate changing ocean chemistry locally

REDUCING OUR CARBON FOOTPRINT

50 more ways to reduce your carbon footprint >

On the Road

Drive fuel-efficient vehicles or choose public transportation. Choose your bike or walk! Don't sit idle for more than 30 seconds. Keep your tires properly inflated.

With your Food Choices

Eat local- this helps cut down on production and transport! Reduce your meat and dairy. Compost to avoid food waste ending up in the landfill

With your Food Choices

Make energy-efficient choices for your appliances and lighting. Heat and cool efficiently! Change your air filters and program your thermostat, seal and insulate your home, and support clean energy sources

By Reducing Coastal Acidification

Reduce your use of fertilizers, Improve sewage treatment and run off, and Protect and restore coastal habitats

TAKE ACTION WITH YOUR COMMUNITY

You've taken the first step to learn more about ocean acidification - why not spread this knowledge to your community?

Every community has their unique culture, economy and ecology and what’s at stake from ocean acidification may be different depending on where you live.  As a community member, you can take a larger role in educating the public about ocean acidification. Creating awareness is the first step to taking action.  As communities gain traction, neighboring regions that share marine resources can build larger coalitions to address ocean acidification.  Here are some ideas to get started:

  1. Work with informal educators, such as aquarium outreach programs and local non-profits, to teach the public about ocean acidification. Visit our Education & Outreach page to find the newest tools!
  2. Participate in habitat restoration efforts to restore habitats that help mitigate the effects of coastal acidification
  3. Facilitate conversations with local businesses that might be affected by ocean acidification, building a plan for the future.
  4. Partner with local community efforts to mitigate the driver behind ocean acidification  – excess CO2 – such as community supported agriculture, bike & car shares and other public transportation options.
  5. Contact your regional Coastal Acidification Network (CAN) to learn how OA is affecting your region and more ideas about how you can get involved in your community
       More for Taking Community Action