Ocean acidification poses multiple challenges for coral reefs on molecular to ecological scales, yet previous experimental studies of the impact of projected CO2 concentrations have mostly been done in aquarium systems with corals removed from their natural ecosystem and placed under artificial light and seawater conditions. The Coral-Proto Free Ocean Carbon Enrichment System (CP-FOCE) uses a network of sensors to monitor conditions within each flume and maintain experimental pH as an offset from environmental pH using feedback control on the injection of low pH seawater. Carbonate chemistry conditions maintained in the -0.06 and -0.22 pH offset treatments were significantly different than environmental conditions. The results from this short-term experiment suggest that the CP-FOCE is an important new experimental system to study in situ impacts of ocean acidification on coral reef ecosystems.

This dataset contains the National Coral Reef Monitoring Program carbonate chemistry data from Guam and the Commonwealth of the Northern Mariana Islands from 2022-04-12 to 2022-08-10. The project monitors changes to coral reef carbonate chemistry over time, at U.S.-affiliated Pacific coral reef sites, through quantifying key chemical parameters that are expected to change with ocean acidification. This effort addresses multiple OAP programmatic mission areas by maintaining the coral reef portion of the OA monitoring network and developing a procedure for data synthesis, assimilation, and distribution. Incorporating an interdisciplinary approach, this project collects, processes, analyzes, and stewards dissolved inorganic carbon (DIC) and total alkalinity (TA) water sample data to document seawater carbonate chemistry at Class 0, I, II, and III climate monitoring sites in coral reef areas of the U.S. Pacific region.

The ocean acidification diel suite is an autonomous instrument package that measures diel variability in coral reef seawater carbonate chemistry. Diel suite surveys are conducted by the NOAA Pacific Islands Fisheries Science Center (PIFSC), Ecosystem Sciences Division (ESD) within coral reef ecosystems across the Pacific Islands Region as part of the NOAA National Coral Reef Monitoring Program (NCRMP). The data provided in this dataset are from diel suites deployed at select sites at Tutuila Island since 2015, during the ESD-led NCRMP missions to American Samoa. Diel suites are deployed on the reef for at least 24 hours to measure chemical and physical parameters at each site. Each diel suite typically consists of various sensors and up to 9 Programmable Underwater Collectors (PUCs) and/or Sub-surface Automated Samplers (SAS). The oceanographic sensors of each diel suite measure parameters such as salinity, temperature, pressure, pH, current direction and magnitude, dissolved oxygen (DO), and/or photosynthetically active radiation (PAR). Seawater samples are collected in four-hour intervals for laboratory analyses of dissolved inorganic carbon (DIC) and total alkalinity (TA). Components of the carbonate system--including pH, pCO2 (partial pressure of carbon dioxide), and aragonite saturation state--are calculated from DIC, TA, temperature, salinity and pressure. Exceptions to the traditional diel suite survey and data collected are noted in each dataset as sensors could be added, removed, or have malfunctioned.

Combining real-time measurements of acidity and calcification, and long-term records from coral skeletons to provide an understanding of how ocean acidity is affecting the marine envrionment and the role of coral reefs in biffering the oceans capacity to absorb greenhouse gas emissions.

This collection contains carbonate chemistry data collected at fixed sites in the Pacific Ocean as part of calibration and validation for Moored Autonomous Partial Pressure of Carbon Dioxide (MAPCO2) buoys. The data from these MAPCO2 buoys complement a national array of moored carbon dioxide buoys across the Pacific, Atlantic, and Caribbean. The buoys are primarily funded by NOAA's Ocean Acidification Program and supported by NOAA's Pacific Marine Environmental Laboratory (PMEL), Atlantic Oceanographic and Meteorological Laboratory (AOML), and Coral Reef Conservation Program (CRCP). Samples are collected every two weeks from predetermined sites around the buoy from the boat or by SCUBA divers. The samples are processed by the AOML where they are analyzed for total alkalinity (TA) and dissolved inorganic carbon (DIC). Using the analyzed TA and DIC, alongside temperature, salinity and depth data, AOML staff calculated other important carbonate chemistry system parameters such as pH, pCO2, and aragonite saturation and reported the results in these data.

This dataset contains carbonate chemistry data collected at both random locations and existing long-term sites in the Florida Keys, Dry Tortugas, Flower Garden Banks and Southeast Florida as part of the NOAA National Coral Reef Monitoring Program (NCRMP). These data are collected and analyzed to assess spatial and temporal variation in the seawater carbonate systems of coral reef ecosystems and include two types of sampling methods. The first method is collected by hand or niskin at the surface, either from the boat or by SCUBA divers. The second method uses subsurface autosamplers where water samples provided in this dataset were collected at a depth of approximately 15m. Samples are either collected singularly or as part of a diurnal set. The samples are processed by the Atlantic Oceanographic Meteorological Laboratory (AOML) where they are analyzed for total alkalinity (TA), dissolved inorganic carbon (DIC) and Spectrophotometric pH. Using the analyzed TA and DIC, alongside temperature, salinity and depth data, AOML staff calculated other important carbonate chemistry system parameters such as pH, pCO2, and aragonite saturation and reported the results in this dataset.