Coastal Maine supports valuable lobster, clam, oyster and other shellfish industries that comprise >90% of Maine’s record $616M landed value last year. Earlier monitoring efforts in Maine and New Hampshire have documented periods of unusually acidic conditions in subsurface waters of Maine’s estuaries, which may be driven by episodic influxes of waters from the Gulf’s nutrient-rich, highly productive coastal current system. Sources of acidity to the estuaries also include the atmosphere, freshwater fluxes, and local eutrophication processes, all modulated by variability imparted by a number of processes.This project is a data synthesis effort to look at long-term trends in water quality data to identify the key drivers of acidification in this area. Extensive data sets dating back to the 1980s (including carbonate system, hydrography, oxygen, nutrients, and other environmental variables) will be assembled, subjected to QA/QC, and analyzed to assess acidification events in the context of landward, seaward and direct atmospheric sources, as may be related to processes operating on tidal to decadal timescales. Such analyses are requisite for any future vulnerability assessments of fishery-dependent communities in Maine and New Hampshire to the effects of coastal acidification.

This project will expand the quantity and quality of ocean acidification (OA) monitoring across Northeastern U.S. coastal waters. The new OA data and incorporation of the world’s first commercial total alkalinity (TA) sensor into our regional observing system (NERACOOS) are designed to supply needed baseline information in support of a healthy and sustainable shellfish industry, and to aid in assessments and projections for wild fisheries. In working with partners to develop this proposal, clear concerns were brought forward regarding the potential impacts of increasing ocean acidity that extend from nearshore hatcheries and aquaculture to broader Gulf of Maine finfish and shellfish industries and their management. Stakeholder input and needs shaped the project scope such that both nearshore and offshore users will be served by TA sensor deployments on partner platforms, including time series data collection at an oyster aquaculture site, on the NOAA Ship of Opportunity AX-2 line, and on federal and State of Maine regional fish trawl surveys. In all, five different deployment platforms will be used to enhance ocean acidification monitoring within the Northeast Coastal Acidification Network (NE-CAN) with significant improvement in temporal and spatial coverage.

 Adding the all-new TA measurement capability to the regional observation network will provide more accurate, certain, and reliable OA monitoring, and an important project objective is to demonstrate and relay this information to regional partners. Data products to be developed from the multi-year measurements include nearshore and offshore baseline OA seasonal time series as well as threshold indices tied to acidification impacts on larval production at the Mook Sea Farm oyster hatchery. An outreach and technical supervision component will include the transfer of carbonate system observing technologies to our partners and to the broader fishing industry, resource management, and science communities. NERACOOS will provide data management and communication (DMAC) services and work towards implementing these technological advances into the IOOS network.

The objective of this project is to make significant strides in bridging the gap between scientific knowledge and current management needs by integrating existing biogeochemical model frameworks, field measurements, and experimental work toward the goals of (1) delineating atmospheric and eutrophication drivers of Chesapeake Bay acidification and improve our understanding of estuarine carbonate chemistry, (2) developing a spatially explicit framework to identify shellfish restoration areas most and least prone to acidification impacts, and (3) better understanding feedbacks associated with future environmental conditions and shellfish restoration goals estuary-wide and within a model tributary. This effort includes (1) a field campaign to make the first comprehensive study of the spatial and temporal variability in the carbonate system in Chesapeake Bay, (2) experiments to quantify both carbonate and nutrient exchange between intact oyster reefs and the surrounding water while measuring response of these fluxes to reef structure and acidification, and (3) an advancement in numerical modeling tools to simultaneously simulate the dynamics of eutrophication, hypoxia, carbonate chemistry, and oyster reef growth and interaction with the water-column under present and future conditions.

In terms of the commercial value of its shellfish and its importance as a finfish breeding ground, the western Gulf of Maine (GOM) is certainly one of the most valuable ecosystems in the United States. Because over 80% of organisms landed in the GOM must utilize calcium carbonate during certain critical life stages, the effects of ocean acidification (OA) on ecosystems are a topic of increasing regional concern. This notion was accentuated by recent demands from marine industry stakeholders and the State Legislature in Maine who convened an Ocean Acidification Commission to study and mitigate the effects of OA. By nature of its cool temperatures and copious freshwater subsidies from both remote and local origins, the western GOM may be particularly sensitive to future acidification stresses (Salisbury et al, 2008; Wang et al, 2013). With the goals of 1) providing data critical for climate studies and local decision support, and 2) understanding of regional processes affecting acidification, we propose to maintain data collection efforts at and proximal to UNH-PMEL acidification buoy. We will deploy, maintain and recover the buoy and its suite of instruments that provide quality oceanographic and carbonate system data. We will supplement these activities with seasonal cruises that map surface regional pCO2 and several surface variables supplemented with hydrographic and optical profiles at six stations along the UNH Wilkinson Basin Line (aka Portsmouth Line), which runs orthogonal to the coast. This in turn will be supplemented with ancillary bottle sampling and all will be used in research aimed at understanding processes controlling the dynamically evolving carbonate system in the western GOM.

The Ecosystem Monitoring program of the Northeast Fisheries Science Center conducts four dedicated cruises per year covering the entire extent of the Northeast United States (NEUS).  NOAA OAP provides funding for the processing of dissolved inorganic carbon (DIC) and total alkalinity (TAlk ) samples from two Ecosystem Monitoring cruises. As part of these cruises, water samples have been taken at a subset of locations and at a range of depths. The depth-discrete nature of this sampling is very important and provides data to complement the more intensive surface sampling conducted by the pCO2 sensors. These samples are used to measure DIC and TAlk and their analyses are conducted by AOML.  In addition, samples for among lab comparisons have been collected. Nutrient samples are also taken and are analyzed at University of Maine. 

Initially, these samples will be used for an analysis comparing the extent of ocean acidification on the NEUS compared to the late 1970's. Subsequently, these samples will be used to provide continued monitoring of the state of ocean acidification. In addition, these samples will be used to better understand the relationship between carbonate chemistry and nutrient speciation on the NEUS. While interpretation of this data is complex, a consolidated analysis is being undertaken to develop an “Ocean Acidification Indicator” for the Northeast Shelf. This metric will provide resource managers and vested stakeholders a concise interpretation of current and near-term expected conditions of acidification in the region. This project also coordinates and cooperates with a number of other regional partners in an attempt to fulfill the regional monitoring vision of National OA Plan.

NOAA academic partners Salisbury and Cai will organize and lead a 34-days cruise covering 12 transects of the U.S. and Canadian coast oceans from Nova Scotia in the north to the Gulf of Maine, Long Island Sound, Mid-Atlantic and Southern Bight regions, ending with a transect off of mid Florida. This cruise will serve as a synoptic characterization of the marine carbonate parameters of the coastal ocean with increased coverage in nearshore areas that have not surveyed in the previous cruises and subsurface dynamics that are not captured from using buoyed assets or ships of opportunity. The climate quality data from these cruises provide an important link to the Global Ocean Acidification Network (GOAN) effort, and serves as a start of a long-term record of dynamics and processes controlling Ocean Acidification (OA) on the coastal shelves. To this end there is an increasing focus on these cruises to perform rate measurements (e.g. NPP/NEP/NEC) for validation measurements of autonomous assets and buoyed assets, for algorithm development utilizing remotely sensed signals that are used to characterize saturation states, and to project the future state of ocean acidification in the project area. 

Dedicated research cruises are used to obtain subsurface measurements and a comprehensive suite of biogeochemical observations to gain a process level understanding of OA. OAP provides funds to carry out the Gulf of Mexico and East Coast Carbon (GOMECC) research cruises every 5 years. These cruises provide a data set of unprecedented quality of physical and chemical coastal ocean parameters that is used both for improved spatial understanding of OA and also to provide a general understanding of changing patterns over time by comparison with previous cruises. The monitoring component is an essential part of the OAP, providing a long-term assessment of changes of biogeochemistry and ecology in response to increasing CO2 atmospheric levels and large-scale changes in coastal dynamics.

The climate quality data from the research cruises provide an important link to the Global Ocean Acidification Network (GOAN) effort, and contribute to a long-term record of dynamics and processes controlling OA on the coastal shelves. The data are used for validation measurements of autonomous assets, applying the data for algorithm development utilizing remotely sensed signals that are used to characterize saturation states, and to project the future state of ocean acidification in the project area.