New Global Ocean Acidification Observing Network Brings Multi-National Approach

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Here, we describe major elements of the Global Ocean Acidification Observing Network (GOA-ON) Requirements and Governance Plan.

Ocean acidification is occurring because the world’s oceans are absorbing increasing amounts of atmospheric carbon dioxide, leading to lower seawater pH and greater acidity. Scientists and policymakers have recognized the need for coordinated, worldwide information about the status of ocean acidification and its ecological impacts. The importance of obtaining such measurements has been endorsed by the United Nations General Assembly, and by many governmental and non-governmental bodies who have assisted the scientific community in developing the Global Ocean Acidification Observing Network (GOA-ON).

Figure 1. The Global Ocean Acidification Observing Network Requirements and Governance Plan. Image Credit:

Figure 1. The Global Ocean Acidification Observing Network Requirements and Governance Plan. Image Credit:

During 2012-3, more than 100 participants from more than 30 nations took part in developing and designing GOA-ON through two international workshops. An active international Executive Council has continued its development. Here, we describe major elements of the GOA-ON Requirements and Governance Plan (Figure 1) which emerged from the workshops, and we cast a broad invitation for wider participation in GOA-ON.

The goals of GOA-ON are to use a collaborative global approach to: 1) measure the status and progress of ocean acidification in open-ocean, coastal, and estuarine environments; 2) understand how ocean acidification affects marine ecosystems; and 3) provide the data necessary to create forecast tools for ocean acidification and its effects. These goals and the nature of ocean acidification itself require that the approach be global.

The GOA-ON Plan identifies ocean acidification as a global issue with local effects. Local effects such as reduced coral growth and decreased shellfish settlement cannot be understood or predicted outside of their global context. In turn, the global condition cannot be truly assessed without including the mosaic of local conditions, which can vary substantially. Coastal pH and carbon conditions can differ from those in the open ocean because of varying local processes such as upwelling, eutrophication and river inputs that can contribute to the signal. GOA-ON observations are designed to span these scales in order to achieve the network’s goals.

Why is a Global Approach to Ocean Acidification Observing Needed?

  • Ocean acidification processes are occurring at global scales; therefore, it is critical to observe ocean acidification on global scales in order to understand the processes controlling its expression correctly.
  • Only data coverage at scales that can nest local observations within the global context will lead to the understanding required to develop predictive skills and early-warning forecast systems.
  • An effective response to ocean acidification requires information based on comparable and consistent data, and reliable forecast products that can be used to inform policymakers and the public worldwide about ocean acidification and its effects on ecosystem health.

While national observational ocean acidification programs now exist or are being developed, their value can be greatly enhanced when brought together at global and linked regional levels. GOA-ON achieves this by building on and integrating existing observing assets including hydrographic surveys, time-series stations, floats and gliders, and volunteer observing ships throughout the world’s oceans and coasts; identifying gaps where capacity must be built; and working to fill these gaps within the international community.

Observations and Modeling Will Inform Science and Polic

A well-coordinated, multidisciplinary and multi-national approach to ocean acidification observations and modeling will provide authoritative evidence to policymakers on fundamental changes to marine ecosystems occurring from pole to equator, and from estuaries to ocean depths. The collation and analysis of global-scale datasets documenting chemical changes and associated biological responses will greatly increase understanding of the processes involved, allowing us to firmly establish impacts attributable to ocean acidification, assess the importance of associated climate change feedbacks, and improve the reliability of projections of future biogeochemical and ecological conditions and their societal consequences.

What Does the Global OA Observing Network Aim to Achieve?

  • Goal 1: Improve our understanding of global ocean acidification conditions.
    • Determine status of and spatial and temporal patterns in carbon chemistry, assessing the generality of ocean acidification status worldwide;
    • Document and evaluate variation in carbon chemistry to infer mechanisms (including biological mechanisms) driving ocean acidification; and
    • Quantify rates of change and trends in carbon chemistry and identify areas of heightened vulnerability or resilience.
  • Goal 2: Improve our understanding of ecosystem response to ocean acidification.
    • Track biological responses to ocean acidification, commensurate with physical and chemical measurements and in synergy with relevant experimental studies and theoretical frameworks; and
    • Quantify rates of change in populations and ecosystems and identify locations and populations of heighted vulnerability or resilience.
  • Goal 3: Acquire and exchange data and knowledge necessary to optimize modeling of ocean acidification and its impacts.
    • Acquire and exchange chemical and biological data for developing and validating models needed to address societally-relevant needs for assessing ocean acidification and its effects and making forecast projections; and
    • Use improved knowledge gained through models to guide Goals 1 and 2 in an iterative fashion.
Conceptually, GOA-ON addresses each of these three goals through the use of a nested design encompassing observations from a wide range of marine environments (from open ocean to coastal waters, including estuaries and coral reefs), and using a variety of integrated and interdisciplinary observing strategies appropriate to the environment of interest.

The GOA-ON plan provides both broad concepts and key critical details for the observing system needed to inform society, decision-makers, and scientists. The plan defines a design strategy for the observing network including GOA-ON’s ecosystem and goal-specific variables; desired spatial and temporal coverage; observing platform-specific recommendations; data quality objectives and requirements; and initial products, outcomes, and applications. International data-sharing arrangements are proposed based on defined data and metadata standards and open access to observing data. While the ocean carbon community has a relatively mature data-sharing process, it is recognized that the addition of coastal sites, as well as biological and ecological data to this framework, will take time and effort to structure.

Efforts are still young. Developing observing systems to detect the impacts of ocean acidification on various types of ecosystems (Figure 2), and within the context of other stressors, has only recently begun. This is especially challenging because the ecosystems vary substantially — tropical, temperate, and polar regional seas; warm and cold-water corals; and nearshore, intertidal and estuarine habitats — and the observing requirements differ as a result, as discussed in the Plan. Further work is needed to refine detailed protocols for relevant biological observations on a habitat- or regionally-specific basis. GOA-ON calls for this process to be informed by results from biological field studies and manipulative experiments.

Figure 2. The Global Ocean Acidification Observing Network must address world environments as diverse as polar seas and coral reefs, among numerous others. The GOA-ON Plan discusses environment-specific requirements. Image Credits: left, Dan Naber, University of Alaska Fairbanks; right, UK Ocean Acidification research programme (UKOA)

GOA-ON builds on, and is conceptually part of, the Framework for Ocean Observation developed by the Global Ocean Observing System (GOOS) and the International Ocean Carbon Coordination Project (IOCCP), while also working closely with the Intergovernmental Oceanographic Commission (IOC) of the United Nations Educational, Scientific and Cultural Organization (UNESCO), the Ocean Acidification International Coordination Center (OA-ICC) of the International Atomic Energy Agency (IAEA), and other relevant bodies. GOA-ON has defined itself to operate effectively within the context of these and other international entities.

The Value of a Fully-Realized Global Network

GOA-ON is not merely a pH monitoring program, nor only composed of sensors in the water. A fully-realized network needs to have the capability to not only track changes in many relevant chemical parameters, such as calcium carbonate (CaCO3) saturation state, but also biological rates and species distributions. Moreover, the network must include the intellectual capacity to sustain asset operation and maintenance, data quality control, data management, analysis, and synthesis product development, as described further in the Plan.

The GOA-ON interactive map offers information for the best-available inventory of global ocean acidification observing platforms. It identifies repeat hydrographic surveys, time-series stations, float and glider observations, and volunteer observing ships.

The GOA-ON interactive map offers information for the best-available inventory of global ocean acidification observing platforms. It identifies repeat hydrographic surveys, time-series stations, float and glider observations, and volunteer observing ships.

A major product of the GOA-ON effort to date is the interactive map of observing system components maintained at the GOA-ON website

Based on GOA-ON contributor input, this map provides continuing updates on the current inventory of various ocean acidification observing assets (Figure 3). The map also provides a tangible means for increasing awareness and coordination between network partners and others with interest in, as well as access to, ocean acidification data being collected around the globe. The strength of GOA-ON will be evidenced by global participation. The website provides easy entry for submitting new GOA-ON observing system components and information. While the map serves only metadata now, ultimately, GOA-ON envisions an on-line data portal where data can be viewed and accessed.





Figure 3. Examples of the diverse observing platforms (assets) that the Global Ocean Acidification Observing Network will utilize; these include moorings, surveys, dock installations, ships, and gliders. These platforms range widely in expense and complexity, but also in the data types yielded and quality assurance/quality control considerations; the latter are addressed in the GOA-ON Plan. Image Credits, left to right: Wendi Ruef, University of Washington; Woods Hole Oceanographic Institution (WHOI); Burke Hales, Oregon State University; UK Ocean Acidification research programme, (UKOA); Andy Suhrbier, Pacific Shellfish Institute; National Oceanic and Atmospheric Administration (NOAA)

At its inception, GOA-ON recognized that the system must be responsive to societal information needs regarding ocean acidification, thus these needs have driven the design of GOA-ON. A key aspect of GOA-ON is recognition that carbon chemistry measurements are required with two different, but defined, levels of uncertainty for addressing two different uses. The measurement uncertainty required in order to track multi-decadal changes at a long-term time-series is different than that needed to determine relative contributions of acidification signal in an estuary or to inform assessments of biological response. GOA-ON has defined each of these two data quality objectives, climate and weather, respectively, in a way that the community can follow consistently.

GOA-ON will maintain consistency in core measurements, but the Plan also states that further development of GOA-ON will require the adoption of advanced new technologies to reliably track ocean acidification and its impacts synoptically. New technologies for monitoring dissolved inorganic carbon, total alkalinity and pH would be beneficial for tracking changes in the marine inorganic carbon system, including those resulting from non-carbon dioxide (CO2) sources of acidification, and for more fully understanding diverse effects on organisms. The biological measurements are admittedly more difficult and complex to measure repeatedly or remotely. Thus technologies for measuring biological abundance, speciation, and rate measurements are important in order to identify biological impacts and adaptations to ocean acidification, especially in coastal zones where globally-driven changes in ocean acidification are augmented by local processes. Advances in technologies will provide critically important information on the changing conditions of ocean acidification and its effects in under-sampled open-ocean and coastal environments.

Implementation of GOA-ON requires coordination and integration internally and externally through linkage to existing international research and observational programs. Leveraging existing infrastructure and monitoring, for both carbon-related work and broader ecological activities, will improve efficiency. However, new infrastructure will be necessary given that considerable observational gaps remain. The GOA-ON Plan identifies some of these gaps. In addition to helping to sustain existing infrastructure and its capabilities, it is essential to identify and prioritize new stations, surveys or measurements urgently needed in under-sampled marine environments and for under-resourced countries to address these gaps.

No single nation can address all the requirements GOA-ON identifies on a truly global basis. GOA-ON is therefore being developed as a collaborative international enterprise, stimulating additional effort and sharing expertise between nations to advance infrastructure development and capacity-building. The existence of the GOA-ON Plan serves the aim that observational network development can occur in a coordinated and consistent fashion needed in order to address issues nations will face as ocean acidification increases. Additional participation in GOA-ON is needed. We welcome your involvement and input.

By Dr. Jan Newton, senior principal oceanographer, University of Washington; lead author of the Global Ocean Acidification Observing Network Plan

Dr. Libby Jewett, director, NOAA Ocean Acidification Program; åÊco-chair, Global Ocean Acidification Observing Network

Dr. Phil Williamson, University of East Anglia School of Environmental Sciences; åÊco-chair, Global Ocean Acidification Observing Network

— This article is based on the Global Ocean Acidification Observing Network: Requirements and Governance PlanåÊ(JA Newton, RA Feely, EB Jewett, P Williamson, J Mathis), published September 2014. Detailed information about this new network’s design, implementation, data strategy and management, and current partnerships can be found in the report.