SOCAN has completed the state-of-the-science webinar series on ocean acidification.  Below you will find the archived webinars and presentations from the series.  Sign up for our listserv for updates on webinars and other SOCAN news.

Archived Webinars:

March 10, 2015:
“A Far-field View of Ocean Acidification in the South Atlantic Bight” by Rik Wanninkhof, NOAA/AOML

Ocean acidification (OA) is a global phenomena with regional impacts that will get increasingly worse with time based on projected  increases in atmospheric CO2 levels.  In this presentation the factors influencing OA in the South Atlantic Bight (SAB) will be discussed with a focus on offshore effects including those caused by changes in water mass characteristics and currents.  Two coastal cruises, measurements on ships of opportunity, and mooring observations sponsored by the NOAA Ocean Acidification Program are used to describe and attribute the ocean acidification patterns in the SAB.

Click here to access presentation slides.



March 18, 2015Estuarine Acidification: A Conceptual Discussion with Examples” presented by Wei-Jun Cai, University of Delaware

Wei-Jun Cai will discuss how estuarine pH is affected by mixing between riverine and anthropogenic carbon dioxide (CO2) enriched seawater and by respiration under various conditions (salinity, temperature and river end-member alkalinity). A few rivers with different levels of weathering products and temperature are selected for the discussion. It is shown here that estuaries receiving low to moderate levels of weathering products exhibit maximum pH decrease in mid-salinity region as a result of anthropogenic COintrusion. Such maximum pH decrease coincides with a mid-salinity minimum buffer zone. In addition, water column oxygen consumption can further depress pH for all simulated estuaries. Recognition of the estuarine minimum buffer zone may be important for studying estuarine calcifying organisms and pH-sensitive biogeochemical processes.

Click here to access presentation slides.


April 7, 2015: Understanding Larval Bivalve Responses to Ocean Acidification” presented by George Waldbusser, Oregon State University

Bivalve larvae have been noted as the canaries in the coal mine of ocean acidification, and are the only commercially important organisms that have been documented in a commercial setting to be responsive to current day changes to marine carbonate chemistry. One of the challenges of understanding organismal responses to ocean acidification is aligning the variable conditions in coastal environments with responses. It has been assumed that since certain organisms are found in variable environments, they must be pre-adapted to withstand the entire range of conditions of a given environment, however decades of work on coastal marine organism recruitment highlights the importance of timing of conditions to critical life history stages. I will present results from hatchery and laboratory based research that shows the timing of this critical stage for bivalve larvae, the mechanisms for their sensitivity, traits that may convey resiliency, and discuss our group’s findings in the context of variable coastal marine systems.

Presentation slides coming soon!


April 21, 2015 Effects of Elevated CO2 on the Early Life-Stages of Marine Fishes and Potential Consequences of Ocean Acidification” presented by R. Christopher Chambers, Research Fishery Biologist, NOAA Northeast Fisheries Science Center, Howard Marine Sciences Laboratory, Highlands, New Jersey

Elevated concentrations of carbon dioxide (CO2) and the acidification of Earth’s oceans are due largely to absorption by seawater of excess, atmospheric CO2 from fossil-fuel combustion. Evidence available about CO2 effects on fish suggests that effects differ across species and perhaps populations, and may interact with other stressors. Further, these differences may also be associated with life-history strategies, habitat use, and parental exposure. This webinar will summarize experimental work from the NOAA Howard Laboratory on the effects of high CO2 on two species of flatfish from the Northwest Atlantic, winter flounder, Pseudopleuronectes americanus, and summer flounder, Paralichthys dentatus, that differ in life history and habitat. Overall, winter flounder displayed increased fertilization success and embryonic survival with increasing CO2  and decreasing temperature. The responses of winter flounder varied with the source of adults (Mid-Atlantic Bight vs Gulf of Maine) with offspring of Gulf of Maine origin more tolerant to elevated CO2 than those from the Mid-Atlantic Bight, but less tolerant to warmer water. Summer flounder exhibited reduced fertilization and embryonic survival with elevated CO2 and colder temperature. Population and species differences in early life-stage responses to elevated CO2 may influence the adaptation potential and persistence of these species at predicted levels of near-future climate change.

Click here to access presentation slides.


May 5, 2015: Crumbling Coral: Cold-water Reefs in the Acidic Northeast Pacific and their Implications for Other Regions of the USA” presented  presented by Leslie Wickes and Peter Etnoyer, NOAA National Centers for Coastal Ocean Science Center for Coastal Environmental Health and Biomolecular Research

Cold-water reefs are fragile, complex ecosystems that extend into the bathyal depths of the ocean, creating three-dimensional structure and habitat for deep-water invertebrates and fishes. The most prolific cold-water reef-building coral is Lophelia pertusa, which occurs at depths where aragonite saturation is three to four times lower than their shallow-water reef counterparts. The current study employed an unprecedented number of ROV dives (n=564, 2003-2014) to document the widespread distribution of a reef-building coral on the U.S. West Coast for the first time, providing empirical evidence of species survival but loss of reef integrity in the naturally acidified conditions. The study found that while Lophelia can persist in the corrosive waters, framework extent, linear extension and skeletal densities were greatly reduced relative to regions such as the North Atlantic and US South Atlantic Bight, where the coral forms more expansive reefs of robust skeleton. Preliminary findings in the South Atlantic Bight suggest corrosive water will also be impinging on Lophelia reefs in this region. The future health of these SAB reefs may depend on both the degree and rate of change, necessitating new monitoring efforts to evaluate carbonate chemistry with respect to cold-water reefs in the Southeast region.

The information presented in this webinar is being prepared for publication. If you have any questions regarding the work, please contact Leslie Wickes at


June 2, 2015: Oceans Acidic and Low in Oxygen: Lessons from Estuarine Organism” presented by Lou Burnett, College of Charleston

Animals living in coastal and estuarine waters along the southern coast of the United States experience dramatic changes in water chemistry and, in particular, they experience carbon dioxide levels far above those predicted in 2100 for the open ocean. This webinar will review the responses of select marine organisms to elevated CO2 showing some of the behavioral, immunological, and physiological responses. The changes organisms experience in CO2 can occur because of their behavior in addition to their habitat. Furthermore, CO2 in coastal waters is tightly linked to oxygen levels, such that during bouts of severe hypoxia waters become acidic. Organisms can adapt to hypoxia, but new evidence suggests that, at least in some crustaceans, adaptation to hypoxia is muted by elevated CO2.


Click here to access presentation slides.


June 16, 2015: Ocean acidification time-series mooring at Grays Reef National Marine Sanctuary” presented by Scott Noakes, Ph.D., The University of Georgia

Operation of the Grays Reef time-series mooring has been a multi-organization effort which has successfully collected high-resolution data since 2006. The mooring is located in the South Atlantic Bight offshore Georgia, USA and within the boundaries of Gray’s Reef National Marine Sanctuary. It sits along the divide between the inner and middle shelf with water depths of 20 m. Water chemistry is primarily controlled by the middle shelf oceanic dynamics, but during heavy rain events, it can be affected by freshwater plumes coming from the numerous rivers along the Georgia and South Carolina coast. Temperature also plays a major role in the partial pressure of carbon dioxide (pCO2) variability with seasonal changes being apparent. During summer months, GRNMS acts as a CO2 source to the atmosphere while during winter months it is a CO2 sink. The benthic community at GRNMS has proven to be hardy enduring large seasonal swings of seawater CO2 and pH. Research planned for the sanctuary will be aimed at determining how these organisms cope with the seasonal changes and how they will adapt to rising seawater CO2 over time.


Click here to access presentation slides.


June 30, 2015: The NECAN story – Linking Ocean and Coastal Acidification science to managers, policymakers, and coastal communities in the northeast United States and Canadian Maritimes” presented by presented by J. Ruairidh Morrison, Northeast Regional Association of Coastal Ocean Observation Systems; Todd Capson; Mel Cote, U.S. EPA; Dwight Gledhill, U.S. NOAA Ocean Acidification Program; Matt Liebman, U.S. EPA; Bill Mook, Mook Sea Farms; Joe Salisbury, University of New Hampshire; Esperanza Stancioff, University of Maine Sea Grant Extension; Cassie Stymiest, Northeast Regional Association of Coastal Ocean Observation Systems; Helmuth Thomas, Dalhousie University; Elizabeth Turner, U.S. NOAA National Centers for Coastal Ocean Science

Public awareness and concern about Ocean Acidification (OA) is growing at the same time as the science is still maturing. In addition to the trend in global OA, near-coastal areas experience Coastal Acidification that is highly dependent on factors such as freshwater and nutrient delivery which are beyond the general increase in atmospheric carbon dioxide, but may be influenced by other human use and climate trends. Addressing these interacting stresses, their influences on Ocean and Coastal Acidification (OCA), and impacts to coastal resources is complex and challenging, both due to the relative paucity of OCA studies and communication gaps between scientists and stakeholders. The Northeast Coastal Acidification Network (NECAN) is a cross border collaboration of scientists, agency representatives, industry and non-governmental organizations that seeks to provide relevant information about OCA to stakeholders in the Canadian Maritimes, Gulf of Maine and Long Island Sound. Efforts to date include a webinar series, state-of-the-science meeting and publications, web-based translation materials and face-to-face interactive stakeholder engagement workshops. The ultimate goal is to develop a regional implementation plan that will outline the information needed by stakeholders, including managers, policymakers, and industry, as well as the required observations, research, and communication mechanisms. This presentation will review these approaches, where we are to date, and the work that remains.

Click here to access presentation slides.


July 14, 2015 : “Leveraging the IOOS Regional Associations to Achieve Ocean Acidification Program (OAP) Goals – The SECOORA and OAP Partnership in the South Atlantic, including discussion of SOCAN” ” presented  by Debra Hernandez, Southeast Coastal and Ocean Observing Regional Association (SECOORA), and Libby Jewett, NOAA Ocean Acidification Program

The NOAA Ocean Acidification Program is working in close collaboration with the Southeast Coastal and Ocean Observing Regional Association (SECOORA) to maximize understanding of how changing ocean chemistry, especially OA, could impact marine resources in the Southeast region. In this webinar, NOAA’s general approach to expanding OA understanding will be presented with special focus on what OAP does independently and together with IOOS, both in the Southeast and in other regions around the US. In addition, we will hear about SECOORA’s operations and infrastructure, which can be leveraged to support OAP mission objectives. One of the joint projects between OAP and SECOORA has been the co-creation of the Southeast Ocean and Coastal Acidification Network (SOCAN) which brings together scientists, managers and stakeholders in an effort to understand the state-of-the-science regarding marine resources and ocean acidification in the southeast, and to determine gaps in both our knowledge and observing/monitoring. We will elaborate on the SOCAN process in an effort to open the discussion to the broader community on effective ways to engage additional stakeholders as we move forward.

Click here to access Libby Jewett’s presentation slides.

Click here to access Debra Hernandez’s presentation slides.

July 28, 2015: Modeling ocean circulation and biogeochemical variability in the Southeast U.S. coastal ocean and Gulf of Mexico” presented  by Ruoying He, North Carolina State University

Changing climate and rising atmospheric CO2 coupled with impacts of human activity, have the potential to dramatically alter coupled hydrologic-biogeochemical processes and associated movement of water, carbon, and nutrients through various terrestrial reservoirs. Such changes will result in dramatic alterations in terrestrial environments, biogeochemistry, and delivery of dissolved and particulate materials into rivers, estuaries, and coastal ocean waters. This may lead to vulnerabilities of coastal ecosystems to warming temperatures, stratification, altered freshwater and nutrient exports, eutrophication, hypoxia, and ocean acidification. Further, coastal and open ocean waters are impacted directly by increasing atmospheric CO2, compounding the effects. This presentation will describe a coupled physical-biogeochemical modeling effort that is aimed at stimulating and examining temporal and spatial variability of coastal circulation and biogeochemical cycling in the southeast U.S. coastal ocean and Gulf of Mexico. The model is driven by realistic atmospheric forcing, open boundary conditions from a data assimilative global ocean circulation model, and observed (or model predicted) freshwater and terrestrial nitrogen input from major rivers. Long-term model simulations were performed, and validated against in-situ and satellite observations. The ultimate goal is todevelop a regional impact assessment and predictive capabilities for coastal ocean ecosystems in the southeast U.S. and Gulf of Mexico to support decision making and management of the combined impacts of ocean acidification (OA), eutrophication, and hypoxia, and to offer a wider marine ecosystem context for carbonate system measurements and monitoring undertaken by NOAA and other agencies. 

Click here to access presentation slides. 



August 18, 2015 : Science, Industry, Management: Perception of Ocean Acidification and Fisheries in Georgia and Florida Virtual Panel ” presented by Brian Hopkinson, University of Georgia; Pat Geer, Georgia DNR; Holly Greening, Tampa Bay Estuary Program; and Curtis Hemmel, Bay Shellfish Co.


A discussion about ocean acidification and potential implications for fisheries in Georgia and Florida. Members of the shellfish industry, natural resource management, and ocean acidification and fisheries research fields will share their expertise and perspective during this virtual panel. Questions from the public will then be posed to our panelists and the panel will conclude with a discussion among panelists and those attending.


Click here to access presentation slides.




August 25, 2015, “Science, Industry, Management: Perception of Ocean Acidification and Fisheries in the Carolinas Virtual Panel” presented by Bob Rheault, East Coast Shellfish Growers Association; Mel Bell, South Carolina Department of Natural Resources; James Morris, Center for Coastal Fisheries and Habitat Research; and Erik Smith, North Inlet-Winyah Bay National Estuarine Research Reserve System


A discussion about ocean acidification and potential implications for fisheries in the Carolinas. Members of the shellfish industry, natural resource management, and ocean acidification and fisheries research fields will share their expertise and perspective during this virtual panel.  

Click here to access presentation slides.








September 15, 2015, “Deciphering the effects of OA on microbial assemblage structure and community function”-  Astrid Schnetzer, Associate Professor, North Carolina State University

Progressing ocean acidification may significantly impact marine plankton community structure and community-level processes. Yet, our ability to predict specific responses is highly limited due to the taxonomic complexity of microbial assemblages and the limitations of the methodological and experimental tools presently available to test specific hypotheses. Research focusing on single microbes (typically well-studied cultured species) has begun to reveal important mechanistic insight into the potential effects of a changing CO2 regime. Much less, however, is known about how mixed (natural) assemblages may respond to ocean acidification. A central question is if the trends and patterns that are observed in microbial communities during short-term manipulations can be extrapolated to the responses of fully acclimated plankton communities over decadal or longer timescales. Further challenges arise from linking shifts in microbial assemblage structure to shifts in biogeochemistry at the base of the food web in response to changed global climate parameters (i.e. pCO2 and temperature).  State-of-the-art molecular approaches allow researchers to tackle these challenges across an array of marine systems. These novel approaches will help us understand the impacts of OA on microbial communities in the SAB.   

Click here to access presentation slides.



Tuesday October 6th, 2015 : Dramatic Variability of the Coastal North Carolina Carbonate System Across Multiple Timescales ” presented Zackary Johnson, Duke University

Increased atmospheric carbon dioxide (CO2) from anthropogenic sources is acidifying marine environments with potentially dramatic implications for the physical, chemical and biological functioning of these ecosystems. If current trends continue, mean ocean pH is expected to decrease by ~0.2 units over the next ~50 years. Yet, at the same time there is substantial spatial and temporal variability in pH and other carbon system parameters in the ocean resulting in regions that already exceed long term projected pH changes, suggesting that short-term variability is an important layer of complexity on top of long term acidification. Thus, in order to develop predictions of future climate change impacts including ocean acidification, there is a critical need to characterize the natural range and variability of the marine CO2 system and the mechanisms responsible for this variability. Here we examine pH and dissolved inorganic carbon (DIC) variability at time intervals spanning 1 hour to >5 years in a dynamic coastal marine system to quantify variability of the carbon system at multiple time scales. Daily and seasonal variability of the carbon system is largely driven by temperature, alkalinity and the balance between primary production and respiration, but high frequency variability (hours to days) is further influenced by water mass movement (e.g. tides) and stochastic events (e.g. storms). Both annual variability (~0.3 units) and diurnal variability (~0.1 units) in coastal ocean acidity are similar in magnitude to long term projections associated with increasing atmospheric CO2 and their drivers highlight the importance of characterizing the complete carbonate system (and not just pH). Short term variability of ocean carbon parameters may already exert significant pressure on some coastal marine ecosystems with implications for ecology, biogeochemistry and evolution and this shorter term variability layers additive effects and complexity, including extreme values, on top of long term trends in ocean acidification.

Presentation slides coming soon!



October 20th, 2015 : Vulnerability and adaptation of US shellfisheries to ocean acidification ” presented by Lisa Suatoni, Natural Resources Defense Council

Ocean acidification is a global, long-term problem whose ultimate solution requires carbon dioxide reduction at a scope and scale that will take decades to accomplish successfully. Until that is achieved, feasible and locally relevant adaptation and mitigation measures are needed. To help to prioritize societal responses to ocean acidification, we present a spatially explicit, multi disciplinary vulnerability analysis of coastal human communities in the United States. We focus our analysis on shelled mollusc harvests, which are likely to be harmed by ocean acidification. Our results highlight US regions most vulnerable to ocean acidification (and why), important knowledge and information gaps, and opportunities to adapt through local actions. The research illustrates the benefits of integrating natural and social sciences to identify actions and other opportunities while policy, stakeholders and scientists are still in relatively early stages of developing research plans and responses to ocean acidification.

Click here to access the PDF of the presentation.


November 17, 2015: “Effects of Ocean Acidification on Tropical Coral Reefs in Florida and the Caribbean” ” presented  by Kimberly Yates, U.S. Geological Survey Coastal and Marine Science Center

Coral reefs are vital to the long-term viability of coastal society, providing economic, recreational, and aesthetic value from which coastal communities thrive. Coral reefs form over thousands of years as reef organisms build calcium carbonate skeletons, creating the three-dimensional structure of reefs that supports high levels of biodiversity and protects coastlines from waves, storm surges and tsunamis.Risk analyses indicate more than 66% of the world’s reefs will be threatened by ocean acidification and warming under ‘business as usual’ climate scenarios. Ocean acidification poses a direct threat to the ability of coral reefs to grow at rates fast enough to keep up with rising sea level. This webinar will summarize the effects of ocean acidification on coral reef community metabolism, the long-term implications for reef structure, and results from recent studies in Florida and the Caribbean on ecosystem-level responses of coral reefs to ocean acidification. Additionally, natural refuges from ocean acidification for reef-building corals and other region-specific factors that may affect coral reefs will be discussed.

Click here to access the PDF of the presentation. 



November 24, 2015“Potential Effects of Climate Change on the Ecotoxicology of Pesticides and Contaminants of Emerging Concern: Implications for Ocean Acidification Interactions”  presented by Geoffrey I. Scott*  1,,  M. H. Fulton  2, P. L, Pennington2, E.F. Wirth2, J. Moore2,  M. DeLorenzo2, G. T. Chandler1, D. E. Porter1, S. Norman 1

Arnold School of Public Health University of South Carolina; 2 NOAA, NOS  NCCOS – Center for Coastal Environmental Health and Biomolecular Research

Increased urbanization is a problem globally, as >55% of the world’s population lives within 50 miles of the coast, 33 of the 50 largest cities in the world are located there, and >80% of world commerce is transported by ships. The compression of >50% of the population into the coastal zone creates a dilemma for environmental managers. Global climate change may cause numerous effects on coastal ecosystems including increased sea level rise, increased temperature, altered precipitation patterns, and ocean acidification. Climate change models when viewed in the face of this accompanying unprecedented, global urbanization, poses even greater impacts on environmental quality and human health as water quality will be greatly affected. Ocean Acidification is one of the major consequences associated with a changing environment. Changes in pH associated with Climate Change may have significant effects on many legacy pollutants as well as Contaminants of Emerging Concern (CECs) found in the environment and may alter their partitioning, persistence and fate/effects within coastal ecosystems. Results will be presented to describe how Climate Change may affect the environment including a discussion of changes in water quality such as temperature, salinity and pH which may alter the ecotoxicology of contemporary use pesticides as well as other contaminants. The resulting effects of these changes on future environmental risk assessment for chemical contaminants will be discussed. Focus will be placed on the urban environment where some of the highest pesticide use occurs, particularly in coastal ecosystems.

Click here to access the PDF of the presentation. 

December 8, 2015: Modeling Coastal Acidification (and Hypoxia) Linkages with Land-Based Nutrient Loads ” presented by John Lehrter, U.S. Environmental Protection Agency

The combination of coastal acidification and hypoxia (O2 < 2 mg/L) is an emerging water quality issue because in combination lower pH and O2 concentration may have a greater impact on coastal fauna than either stressor alone. Further, the prevalence of both low pH and low O2 in coastal waters is increasing due to increasing land-based nutrient loads and uptake of CO2 by the global ocean. Addressing these issues simultaneously is attractive because in effect the decreasing O2 and increasing respiratory CO2 that contribute to the occurrence of coastal acidification and hypoxia are simply different sides of the respiratory equation and should respond proportionally to changes in nutrient loading. However, while the conceptual model for the nutrient linkage is well-developed, quantifying changes in pH and O2 related to nutrient loading in a specific system remains a challenge due to the complex physical, chemical, and biological processes that occur. For example, physical processes such as water-column vertical stratification and biogeochemical processes such as primary production and sediment diagenesis vary in time and space in a system and regulate a system’s susceptibility to nutrients and the occurrence of low pH and hypoxia. Since we lack extended temporal and spatial observations of these phenomena for most systems, models are needed to extrapolate and predict temporal and spatial patterns in pH and O2 in relation to nutrients. Here, I will present model development, application, and challenges to relate nutrient loads to coastal acidification and hypoxia using a case study of the northern Gulf of Mexico in the area influenced by the Mississippi River. The ultimate goal is to predict how variation in nutrient loads, atmospheric CO2, and regional climate change affects coastal pH and O2. This can help decision-makers determine the most effective policies for managing and mediating nutrient pollution, coastal acidification and hypoxia at local and global scales.

Click here to access the PDF of the presentation.


January 5, 2016: “Acidification and Hypoxia in the Shallows – Patterns, Research Approaches, and Effects –  presented by Denise Breitburg, Smithsonian Environmental Research Center
Respiration-driven, co-occurring acidification and hypoxia is a natural phenomenon that is exacerbated by human influences on coastal ecosystems. On a local to regional scale, nutrient loads increase biomass, thus increasing respiratory release of CO2and depletion of O2. Globally, increasing temperatures increase metabolic rates of aquatic organisms and can influence weather and current patterns that control rates of reaeration. In extreme shallow waters of estuaries and similar systems, light, temperature and tides influence the net balance of photosynthesis and respiration, creating diel and tidal fluctuations in dissolved oxygen and pCO2 (reflected in the much more common pH measurements). In shallow areas of Chesapeake Bay, for example, pH can vary by more than one full unit and dissolved oxygen can vary from near zero to supersaturated levels on a daily basis. The temporal patterns we’ve documented can be far more complex and spatially variable than classic diel cycles.

We have developed a LabVIEW controlled experimental system to test the individual and simultaneous effects of cycling dissolved oxygen and pH on common estuarine species. Our experiments indicate that animals we tested (the eastern oyster, Crassostrea virginica, and the Atlantic and inland silversides, Menidia menidia and M. beryllina) can be affected by diel cycling acidification and hypoxia that occurs in their natural habitat. But at least in some cases, they also showed the ability to acclimate to or compensate for negative effects. Cycling, per se, sometimes had different effects than constant exposures. Among the effects of diel-cycling acidification we found were a slight stimulation of oyster filtration rates, altered immune responses of oysters, decreased growth of oyster spat in low salinity conditions, and an increased sensitivity of fish to hypoxia.

Recording of webinar coming soon!

January 7, 2016: Integrating Multiple Experimental Approaches to Understand Climate Change Ecosystem Impacts: A Coral Reef Example –  presented by David I. Kline, Associate Project Scientist, Scripps Institution of Oceanography, University of California
Ocean acidification (OA) research seeks to understand how marine ecosystems will respond to changes in seawater carbonate chemistry in combination with other environmental perturbations such as warming, eutrophication, and deoxygenation. I will discuss the effectiveness and limitations of current research approaches used to address this goal. A diverse combination of approaches is essential to decipher the consequences of OA to marine organisms, communities, and ecosystems. Consequently, the benefits and limitations of each approach must be considered carefully. I will discuss my own coral reef research and describe how a combination of aquarium, mesocosm, FOCE and in situ reef studies were used to determine how the balance between reef growth and dissolution would change in a high CO2 future.  
Recording of webinar coming soon!