The Friends of GOA-ON Build OA Reporting Capacity in Underserved Areas

Chair: Libby Jewett

Mark J. Spalding (1)
1 The Ocean Foundation, Washington, DC, 20036, USA

Background
During the 2014 “Our Ocean” Conference hosted by the State Department, Secretary of State John Kerry pledged support for building the observing capabilities of the Global Ocean Acidification Observing Network (GOA-ON). During that conference, The Ocean Foundation accepted the honour to host the Friends of GOA-ON, a non-profit collaboration targeted at attracting funding in support of the GOA-ON’s mission to fulfil the scientific and policy needs for coordinated, worldwide information-gathering on ocean acidification and its ecological impacts.
Recently, NOAA Chief Scientist Richard Spinrad and his UK counterpart, Ian Boyd, in their Oct. 15, 2015 New York Times OpEd, “Our Deadened, Carbon-Soaked Seas”, recommended investing in new ocean sensing technologies, particularly those developed during the 2015 Wendy Schmidt Ocean Health XPRIZE competition, to provide the basis for robust forecasting in coastal communities lacking the capability for OA monitoring and reporting, particularly in the Southern Hemisphere.

Methods
To increase OA monitoring and reporting capacity in Africa, an area where there are huge information and data gaps, GOA-ON has began a pilot program in Mozambique to hold training workshops for local scientists to learn how to operate, deploy and maintain OA sensors as well as collect, manage, archive and upload OA data to global observing platforms.

Findings
A partnership between the U.S. State Department (via their Leveraging, Engaging, and Accelerating through Partnerships (LEAP) program), the public-private partnership ApHRICA, GOA-ON, and the XPRIZE Foundation, will provide resources to begin OA monitoring in Africa, enhance capacity-building workshops, facilitate connections to global monitoring efforts, and explore a business case for new ocean acidification sensor technologies.

Conclusions
This partnership seeks to achieve the Secretary’s goal to increase worldwide coverage of the GOA-ON and train monitors and managers to better understand the impacts of ocean acidification, especially in Africa, where there is very limited ocean acidification monitoring.

Disentangling ocean acidification organismal effects through an experimental system that allows automated and dynamic carbonate chemistry manipulations

Chair: Thomas Trull

Iria Gimenez (1)*, George G. Waldbusser (2), Burke Hales (3)

1 College of Earth, Ocean and Atmospheric Sciences, Oregon State University, Corvallis, OR, 97331, USA
2 College of Earth, Ocean and Atmospheric Sciences, Oregon State University, Corvallis, OR, 97331, USA
3 College of Earth, Ocean and Atmospheric Sciences, Oregon State University, Corvallis, OR, 97331, USA

Background
Ocean acidification (OA)-driven pCO2, pH, and saturation state changes are tightly coupled within oligotrophic open ocean regimes, but can decouple across regimes or within dynamic coastal and estuarine waters. Laboratory OA experiments relying on CO2 gas injection or addition of mineral acid result in covariance of these carbonate system variables distinct from natural settings where they may change simultaneously and independently. These approaches do not allow determination of the carbonate parameter driving sensitivity, and thus difficult mechanistic interpretation of physiological responses.

Methods
Building on previous batch-culture work, we developed a system that allows long-term experimental decoupling of carbonate parameters. The system independently manipulates alkalinity and dissolved inorganic carbon (DIC) to and consists of two parts: 1) an analyzer that monitors source-water pCO2 and DIC in real time, 2) a dynamic feed-forward controller system that performs automated, precise acid and carbonate reagent additions through computer-controlled syringe pumps.

Findings
After overcoming several implementation challenges, we have been able to simultaneously manipulate water on three different experimental treatments to results less than 3% from respective DIC and alkalinity targets. Preliminary tests show that extremely sensitive embryos and young larvae develop and grow normally in water manipulated to mimic control chemistry, while harmful conditions resulted in poor larval success. We will present data from precision and accuracy tests and preliminary physiological data from experiments to evaluate saturation state and pH integrated effects over the entire mussel larval period.

Conclusions
We constructed an experimental system providing opportunity to run OA experiments over long timescales in a flow-through setting providing more consistent experimental conditions. This system allows better mechanistic understanding of physiological responses to OA through a clear separation of effects due to different carbonate parameters and can be used on multiple organisms, allowing greater understanding of OA responses in ocean-margin waters that show decoupling.

Continuous pCO2 time series from ocean networks Canada cabled observatories on the Northeast Pacific shelf-edge/upper slope and in the Sub-Tidal Arctic

Chair: Libby Jewett

S. Kim Juniper (1)*, Akash Sastri (1), Steven Mihaly (1), Jeremy Whitehead (2), Brent Else (2), Helmuth Thomas (3) and Lisa Miller (4)

1 Ocean Networks Canada, University of Victoria, Canada
2 Department of Geography, University of Calgary, Canada
3 Dalhousie University, Halifax, Canada
4 Institute of Ocean Sciences, Department of Fisheries and Oceans, Canada

Continuous monitoring platforms contribute to our understanding of ocean change by resolving variability that can be a defining component of long-term change and a confounding factor in its detection by occasional measurements. The reliability of pCO2 sensors technologies has progressed to the point where months-long field recordings from autonomous and cabled sensor platforms can be used to document seasonal and higher frequency variability in pCO2 and its relationship to oceanographic processes. We will present pCO2 time-series data from deployments on two Ocean Networks Canada cabled platforms: a bottom-moored, vertical profiler at the edge of the continental shelf off Vancouver Island, Canada, and a seafloor platform at subtidal depth in the Canadian Arctic at Cambridge Bay, Nunavut. Both platforms support Pro-Oceanus pCO2 sensors together with other oceanographic instruments, and streamed continuous data to a shore-based archive. The vertical profiler deployment yielded a 7-month time series of pCO2 and corresponding oceanographic sensor data from 5 vertical profiles per data, from 400m depth to surface waters, centered around local noon. Step-wise profiles during the downcast provided the most reliable pCO2 data, permitting the sensor to equilibrate to the broad range of pCO2 concentrations encountered over this depth interval. The Arctic sensor platform was deployed in August 2015 and has been recording increasing pCO2 concentrations since the formation of sea ice. We will review the major characteristics of these two time series and the performance of the sensors in relation to the operational conditions encountered in vertical profiling and continuous operation in subzero seawater. We will also review the under-ice performance of a pH sensor and a prototype optical CO2 sensor that are deployed on the same Arctic platform.

Continuous monitoring of seawater pH and pCO2 in a temperate estuary

Chair: Libby Jewett

John Runcie (1)

1 Aquation Pty Ltd, Umina Beach, NSW, 2257, AUSTRALIA

Background
Understanding the carbon chemistry of seawater is essential to ocean acidification research. The drivers of small-scale and short-term changes in nearshore carbon chemistry and their interactions are complex. Continuous measurements that identify fluctuating chemistry can help in the identification and characterisation of these drivers. Recent research efforts to continuously measure seawater carbon chemistry have focussed on pH determination using ISFET and spectrometric techniques. Here we present results of an alternate approach to pH measurement using fluorescence. In addition we also report pCO2 determinations using the same fluorescence-based technology.

Methods
Specially made artificial substrates respond to changes in pH and pCO2 by changes in the lifetimes of fluorescence decay. These changes are compared against the lifetimes of an invariant reference. Both pH and pCO2 measurements were made from a single device located in an estuary in NSW, with virtually simultaneous measurements made regularly for several weeks.

Findings
The fluorescence-based technique provided a useful time-series for both pH and pCO2 of surface waters in the estuary. Variations over the course of the day and night were subtle but could reasonably be distinguished from background variability. Drift due to photodegradation of the fluorophore was kept to a minimum by minimising exposure to ambient light. Seawater carbon chemistry composition was calculated using the measured parameters.

Conclusions
The fluorescence lifetimes-decay approach used here to measure both pH and pCO2 in situ provides sufficient information to calculate the carbon chemistry of ambient seawater. The simplicity of the technique is attractive and means it is less susceptible to mechanical failure. An additional potential advantage of this approach is an independence to external pressure, however this will be examined in detail in a separate future study.

An ocean acidification Monitoring Network for the Caribbean: A Collaboration of Nations

Chair: Thomas Trull

James C. Hendee (1)*, Derek Manzello (1), Adrienne Sutton (2)

1 Ocean Chemistry and Ecosystems Division, Atlantic Oceanographic and Meteorological Laboratory, National Oceanic and Atmospheric Administration, Miami, FL USA 33149
2 NOAA Pacific Marine Environmental Laboratory, Seattle, WA, 98115, USA and University of Washington, Joint Institute for the Study of the Atmosphere and Ocean, Seattle, WA, 98195, USA

Background
Even though studies over the last two decades have demonstrated that reef-building corals are sensitive to changes in carbonate chemistry, ocean acidification research and monitoring in tropical coral ecosystems is lacking.

Methods
To address this need, researchers at the Atlantic Oceanographic and Meteorological Laboratory (AOML), of the National Oceanic and Atmospheric Administration, in Miami, FL (USA), have devised and deployed in situ monitoring stations (Coral Reef Early Warning System, or CREWS) for purposes of determining long-term environmental changes at various coral reef habitats since 2000 and are now building off these efforts to address ocean acidification. The Caribbean Community Climate Change Center has recently entered into a collaboration with AOML to assist in the deployment and information management (including ecological forecasting) of CREWS stations at many countries throughout the Caribbean, through funding by the European Union. AOML has recently in turn collaborated with researchers from the Pacific Marine Environmental Laboratory (PMEL) to devise a new buoy that has the standard CREWS-type of monitoring elements plus ocean acidification monitoring instruments. These newly designed stations are slated for deployment at a minimum of six new countries over the next several years and will represent the beginning of a Caribbean-wide ocean acidification monitoring network to inform coral reef research and management communities seeking to understand the impacts of ocean acidification.

Findings
Ocean acidification monitoring requires sophisticated monitoring equipment and methods. Providing near real-time monitoring of ocean acidification provides researchers a unique look at witnessing diurnal and seasonal events in near real-time and provides them the feedback to witness and sample events as, or shortly after, they occur. The instrumental architecture and information system also provides meteorological data to help interpret the oceanographic events.

Conclusions
Implementation of a Caribbean-wide network provides a large regional look at the process of ocean acidification.

A multi-sensor system for the direct measurement of Ω, pH, and carbonate

Chair: Libby Jewett

Christina M. McGraw (1), Wayne D.N. Dillon (1), Hugh L. Doyle (2), Peter W. Dillingham (1), Peter G. Lye (1), Philip W. Boyd (2), Catriona L. Hurd (2)

1 School of Science and Technology, University of New England, Armidale, 2351, New South Wales, Australia
2 Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, 7005, Tasmania, Australia

Background
A multi-sensor system was developed to monitor short-term carbonate variability in the laboratory and field. The system combines a saturation state (Ω) sensor with carbonate and pH sensors to measure real-time changes in carbonate chemistry.

Methods
The Ω probe detects real-time dissolution and precipitation of calcium carbonate. For example, thin films of CaCO3 with known morphology and thickness can be deposited on the Ω sensor through chemically-controlled deposition. With a sub-second response time, the sensor can then be used to study real-time dissolution under a range of environmental conditions. To complement these measurements, the Ω sensor was combined with a range of seawater sensors we previously developed for ocean acidification studies. To measure carbonate, solid-contact fabrication techniques were used to produce carbonate ion-selective electrodes. The same fabrication techniques were used to produce hydrogen ion-selective electrodes and reference electrodes. The carbonate, hydrogen, and reference electrodes were produced on a single $5 disposable cartridge.

Findings
The ion-selective electrode cartridge and Ω sensor were incorporated into a single multi-sensor array. This device was tested in solutions of known DIC and AT and under a range of current and future conditions. The response of the multi-sensor array varied as expected to the range of solutions and both short-term and long-term variability.

Conclusions
To our knowledge, the multi-sensor array is the first sensor that directly measures Ω, pH, and carbonate. When deployed in the laboratory or field, the device can be used for real-time identification of under-saturation events.

Sensors for CO2 Partial Pressure (pCO2), Total Alkalinity (TA) and pH – Recent Developments and Field data

Chair: Libby Jewett
Peer Fietzek (1,2), Carsten Frank (1), Steffen Aßmann (1)

1 Kongsberg Maritime Contros GmbH, Kiel, 24148, Germany

2 GEOMAR Helmholtz Centre for Ocean Research Kiel, Kiel, 24105, Germany

Background
The motivation for CO 2 determination in water is manifold and extends from scientific applications (i.e. ocean acidification studies) to industrial usage (i.e. CCS). Due to the chemical properties of CO2, i.e. formation and dissociation of carbonic acid, a complete determination of the marine carbonate system is required for many studies. Therefore, the measurement of TA and pH experiences great attention, both as individual measurement quantities as well as within CO2 system determination exercises.

Methods
A proven method to determine CO 2 concentrations in gas is by means of infrared absorption spectrometry, i.e. NDIR detectors. Semi-permeable membranes enable sensor designs, in which a gas headspace is equilibrated and allows for usage of NDIR detectors in e.g. CO2 underwater sensors.
TA is determined by acidic titration of seawater samples with subsequent CO 2 stripping and pH determination. Recent progress in the field of automated fluid analysis now enables realization of autonomous analysers that unattendedly carry out this task at high precision. Likewise dedicated sensor designs can be realized that directly determine the pH of discrete water samples or in a semi-continuous fashion at high quality.

Findings
CONTROS HydroC ® CO2 sensors have been used within multiple applications and on various platforms over the last years. Recent application include coastal deployments that enabled analysis of carbonate system dynamics.
The CONTROS HydroFIA ® TA is a new commercially available analyser for total alkalinity. First field measurements highlight its potential further enhanced through ongoing developments within high-class international research projects (i.e. AtlantOS, TAACT). Similar projects target the development and assessment of state of the art analysers for pH (i.e. BONUS PINBAL).

Conclusions
Numerous applications within aquatic sciences benefit from the autonomous determination of carbonate system parameters pCO2, TA and pH. This contribution presents the development status of and results obtained with state of the art sensor technology.

Monitoring Ocean Acidification in the Arctic Ocean and the Norwegian seas

Chair: Libby Jewett

Melissa Chierici (1)*, Agneta Fransson (2), Ingunn Skjelvan (3) , Kai Sørensen (4), Andrew King (4), Marit Norli (3), Helene Lødemel (
1)

1 Institute of Marine Research and FRAM-High North Centre of Climate and the Environment, Tromsø, 9294 Norway
2 Norwegian Polar Institute, Fram Centre, Tromsø 9296, Norway
3 UniResearch, Bergen, Norway

Background
Increased attention and need for advice on ocean acidification and its consequences for the marine ecosystem motivated the Norwegian government to fund OA monitoring projects. Since 2011, two major research projects with multi-institutional participants were established to investigate the carbonate system and ocean acidification state in Norwegian(Norwegian Environment Agency) and Arctic waters (OA Flagship in the FRAM centre). The Fram Strait is the main gateway for exchange of Arctic and Atlantic waters entering the Arctic Ocean and studies here may give an integrated signal of the climate stressors affecting the Ocean acidification state in the Arctic Ocean. One of the aim of the repeated surveys in the Norwegian Sea is to investigate the trends in pH, which has been observed to decrease at a faster rate than modelled mainly due to the influence of anthropogenic CO2. Another aim is to investigate the carbonate system state and variability in some of the major Cold Water Coral reef areas, which has been little investigated.

Methods
We use a combination of sampling platforms such as water column measurements (mainly in winter) along repeated transects and underway surface water carbonate system measurements for seasonal studies.
Water samples are collected and analysed either directly onboard or preserved for post-cruise analysis in laboratory. Samples are determined for total dissolved inorganic carbon (CT), total alkalinity (AT), pH and in surface waters underway fugacity of carbon dioxide (fCO2) combined with surface water sampling for analysis of either CT, AT or pH.

Findings
The variability is large, which are partly due to mixing of different water masses. Along the Norwegian coast, total carbon (CT) and total alkalinity (AT) are influenced by the fresh and cold coastal current, and the carbon values are low. A similar effect is seen at the marginal ice zone in the northern Barents Sea. Biological activity is also an important driver for the observed changes in the carbonate system and the effects of this are seen at some locations. Low pH values due to increased CO2-content are seen at some locations, e.g. in the southern Norwegian Sea. In 2014, aragonite saturation averaged over all depths and stations is 1.6 in Skagerrak (in February), 1.7 and 1.7 in southern and northern Norwegian Sea, respectively, 1.9 the in Barents Sea Opening, and 1.8 in the North Eastern Barents Sea (in September). Low aragonite saturation is seen in the bottom water, and in the Barents Sea and Skagerrak this value is around 1.4. Deeper than about 1900 m in the Norwegian Sea the water is undersaturated with respect to aragonite, while supersaturation is seen at a few locations during winter in the Skagerrak surface water.

Conclusions
This is five years of monitoring of the OA state and we start to reveal trends, but they cannot be confirmed and the drivers are not yet fully understood. Further monitoring of the carbonate system is required to assess trends in and drivers of ocean acidification. Annual sampling of the water column in winter time is not satisfactory to address and extract the biological and physical processes behind the natural variability. Data is used in models to improve future projections of OA state. Seasonal and frequent sampling in surface waters results in understanding of CO2 uptake and main drivers for seasonal change.

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