ALBERT

Description: The Surface Ocean CO2 Atlas (SOCAT) is an effort by the international marine carbon research community. It aims to improve access to carbon dioxide measurements in the surface oceans by regular releases of quality controlled and fully documented synthesis and gridded fCO2 (fugacity of carbon dioxide) products. SOCAT version 2 presented here extends the data set for the global oceans and coastal seas by four years and has 10.1 million surface water fCO2 values from 2660 cruises between 1968 and 2011. The procedures for creating version 2 have been comparable to those for version 1. The SOCAT website (http://www.socat.info/) provides access to the individual cruise data files, as well as to the synthesis and gridded data products. Interactive online tools allow visitors to explore the richness of the data. Scientific users can also retrieve the data as downloadable files or via Ocean Data View. Version 2 enables carbon specialists to expand their studies until 2011. Applications of SOCAT include process studies, quantification of the ocean carbon sink and its spatial, seasonal, year-to-year and longer-term variation, as well as initialisation or validation of ocean carbon models and coupled-climate carbon models.

Description: This paper defines the best practices for documenting ocean acidification (OA) metadata and presents a framework for an OA metadata template. Metadata is structured information that describes and locates an information resource. It is the key to ensuring that a data set will survive and continue to be accessible into the future. With the rapid expansion of studies on biological responses of organisms to OA, the lack of a common metadata template to document the resulting data poses a significant hindrance to effective OA data management efforts. In this paper, we present a metadata template that can be applied to a broad spectrum of OA studies, including those studying the biological responses of organisms to OA. The "variable metadata section", which includes the variable name, observation type, whether the variable is a manipulation condition or response variable, and the biological subject on which the variable is studied, forms the core of this metadata template. Additional metadata elements, such as investigators, temporal and spatial coverage, platforms for the sampling, data citation, are essential components to complete the template. We also explain the structure of the template, and define many metadata elements that may be unfamiliar to researchers. Template availability. - Available at: http://ezid.cdlib.org/id/doi:10.7289/V5C24TCK. - DOI: doi:10.7289/V5C24TCK. - NOAA Institutional Repository Accession number: ocn881471371.

Description: For version 2 of the Global Ocean Data Analysis Project (GLODAPv2) we collated data from 724 scientific cruises covering the global ocean: data assembled in the previous efforts GLODAPv1.1 (Global Ocean Data Analysis Project version 1.1) in 2004, CARINA (CARbon IN the Atlantic) in 2009/10, and PACIFICA (PACIFic ocean Interior CArbon) in 2013, and an additional 168 cruises. Twelve core parameters (salinity, oxygen, macronutrients, seawater CO2 chemistry parameters and halogenated transient tracers) have been subjected to extensive quality control including systematic evaluation of biases between cruises. The data are available in two formats: (i) as submitted but updated to WOCE exchange format whenever required, and (ii) as a merged and calibrated data product. In the latter, adjustments have been applied to remove significant biases, respecting occurrences of any known or likely time trends. Adjustments determined by previous efforts have been re-evaluated. Hence, GLODAPv2 is not a simple merge of previous collections and some new data, but represents a unique, internally consistent data product. The original data and their documentation and doi codes are available at the Carbon Dioxide Information Analysis Center (http://cdiac.ornl.gov/oceans/GLODAPv2/). This site also provides access to the calibrated data product, which is provided as a single global file or 4 regional ones: the Arctic, Atlantic, Indian, and Pacific Oceans, under the doi:10.3334/CDIAC/OTG.NDP093_GLODAPv2. The product files also include significant ancillary and approximated data. The latter were obtained either by interpolation of, or by calculation from, measured data. This paper documents the GLODAPv2 history, methods, and products, including a broad overview of the secondary quality control results. The magnitude of and reasoning behind the adjustments are available on a per cruise and parameter basis in an online Adjustment Table.

Description: In an intensifying effort to track ocean change and distinguish between natural and anthropogenic drivers, sustained ocean time-series measurements are becoming increasingly important. Advancements in the ocean carbon observation network over the last decade, such as the development and deployment of Moored Autonomous pCO2 (MAPCO2) systems, have dramatically improved our ability to characterize ocean climate, sea–air gas exchange, and biogeochemical processes. The MAPCO2 system provides high-resolution data that can measure interannual, seasonal, and sub-seasonal dynamics and constrain the impact of short-term biogeochemical variability on carbon dioxide (CO2) flux. Overall uncertainty of the MAPCO2 using in situ calibrations with certified gas standards and post-deployment standard operating procedures is 〈 2 μatm for seawater partial pressure of CO2 (pCO2) and 〈 1 μatm for air pCO2. The MAPCO2 maintains this level of uncertainty for over 400 days of autonomous operation. MAPCO2 measurements are consistent with ship-board seawater pCO2 measurements and GLOBALVIEW-CO2 boundary layer atmospheric values. Here we provide an open ocean MAPCO2 data set including over 100 000 individual air and seawater pCO2 measurements on 14 surface buoys from 2004 through 2011 and a description of the methods and data quality control involved. The climate quality data provided by the MAPCO2 has allowed for the establishment of open ocean observatories to track surface ocean pCO2 changes around the globe. Data are available at doi:10.3334/CDIAC/OTG.TSM_NDP092 and cdiac.ornl.gov/oceans/Moorings/ndp092.

Description: In an intensifying effort to track ocean change and distinguish between natural and anthropogenic drivers, sustained ocean time series measurements are becoming increasingly important. Advancements in the ocean carbon observation network over the last decade, such as the development and deployment of Moored Autonomous pCO2 (MAPCO2) systems, have dramatically improved our ability to characterize ocean climate, sea–air gas exchange, and biogeochemical processes. The MAPCO2 system provides high-resolution data that can measure interannual, seasonal, and sub-seasonal dynamics and constrain the impact of short-term biogeochemical variability on carbon dioxide (CO2) flux. Overall uncertainty of the MAPCO2 using in situ calibrations with certified gas standards and post-deployment standard operating procedures is 〈 2 μatm for seawater partial pressure of CO2 (pCO2) and 〈 1 μatm for air pCO2. The MAPCO2 maintains this level of uncertainty for over 400 days of autonomous operation. MAPCO2 measurements are consistent with shipboard seawater pCO2 measurements and GLOBALVIEW-CO2 boundary layer atmospheric values. Here we provide an open-ocean MAPCO2 data set including over 100 000 individual atmospheric and seawater pCO2 measurements on 14 surface buoys from 2004 through 2011 and a description of the methods and data quality control involved. The climate-quality data provided by the MAPCO2 have allowed for the establishment of open-ocean observatories to track surface ocean pCO2 changes around the globe. Data are available at doi:10.3334/CDIAC/OTG.TSM_NDP092 and http://cdiac.ornl.gov/oceans/Moorings/ndp092.

Description: As a response to public demand for a well-documented, quality controlled, publically available, global surface ocean carbon dioxide (CO2) data set, the international marine carbon science community developed the Surface Ocean CO2 Atlas (SOCAT). The first SOCAT product is a collection of 6.3 million quality controlled surface CO2 data from the global oceans and coastal seas, spanning four decades (1968–2007). The SOCAT gridded data presented here is the second data product to come from the SOCAT project. Recognizing that some groups may have trouble working with millions of measurements, the SOCAT gridded product was generated to provide a robust, regularly spaced CO2 fugacity (fCO2) product with minimal spatial and temporal interpolation, which should be easier to work with for many applications. Gridded SOCAT is rich with information that has not been fully explored yet (e.g., regional differences in the seasonal cycles), but also contains biases and limitations that the user needs to recognize and address (e.g., local influences on values in some coastal regions).

Description: A well documented, publicly available, global data set for surface ocean carbon dioxide (CO2) parameters has been called for by international groups for nearly two decades. The Surface Ocean CO2 Atlas (SOCAT) project was initiated by the international marine carbon science community in 2007 with the aim of providing a comprehensive, publicly available, regularly updated, global data set of marine surface CO2, which had been subject to quality control (QC). SOCAT version 1.5 was made public in September 2011 and holds 6.3 million quality controlled surface CO2 data from the global oceans and coastal seas, spanning four decades (1968–2007). The SOCAT gridded data is the second data product to come from the SOCAT project. Recognizing that some groups may have trouble working with millions of measurements, the SOCAT gridded product was generated to provide a robust regularly spaced fCO2 product with minimal spatial and temporal interpolation which should be easier to work with for many applications. Gridded SOCAT is rich with information that has not been fully explored yet, but also contains biases and limitations that the user needs to recognize and address.

Description: A well-documented, publicly available, global data set of surface ocean carbon dioxide (CO2) parameters has been called for by international groups for nearly two decades. The Surface Ocean CO2 Atlas (SOCAT) project was initiated by the international marine carbon science community in 2007 with the aim of providing a comprehensive, publicly available, regularly updated, global data set of marine surface CO2, which had been subject to quality control (QC). Many additional CO2 data, not yet made public via the Carbon Dioxide Information Analysis Center (CDIAC), were retrieved from data originators, public websites and other data centres. All data were put in a uniform format following a strict protocol. Quality control was carried out according to clearly defined criteria. Regional specialists performed the quality control, using state-of-the-art web-based tools, specially developed for accomplishing this global team effort. SOCAT version 1.5 was made public in September 2011 and holds 6.3 million quality controlled surface CO2 data points from the global oceans and coastal seas, spanning four decades (1968–2007). Three types of data products are available: individual cruise files, a merged complete data set and gridded products. With the rapid expansion of marine CO2 data collection and the importance of quantifying net global oceanic CO2 uptake and its changes, sustained data synthesis and data access are priorities.

Description: Water column data of carbon and carbon-relevant hydrographic and hydrochemical parameters from 188 previously non-publicly available cruise data sets in the Arctic, Atlantic and Southern Ocean have been retrieved and merged into a new database: CARINA (CARbon IN the Atlantic). The data have gone through rigorous quality control procedures to assure the highest possible quality and consistency. The data for the pertinent parameters in the CARINA database were objectively examined in order to quantify systematic differences in the reported values, i.e. secondary quality control. Systematic biases found in the data have been corrected in the data products, i.e. three merged data files with measured, calculated and interpolated data for each of the three CARINA regions, i.e. Arctic, Atlantic and Southern Ocean. Ninety-eight of the cruises in the CARINA database were conducted in the Atlantic Ocean, defined here as the region south of the Greenland-Iceland-Scotland Ridge and north of about 30° S. Here we present an overview of the Atlantic Ocean synthesis of the CARINA data and the adjustments that were applied to the data product. We also report details of the secondary QC for salinity for this data set. Procedures of quality control – including crossover analysis between stations and inversion analysis of all crossover data – are briefly described. Adjustments to salinity measurements were applied to the data from 10 cruises in the Atlantic Ocean region. Based on our analysis we estimate the internal accuracy of the CARINA-ATL salinity data to be 4.1 ppm. With these adjustments the CARINA database is consistent both internally as well as with GLODAP data, an oceanographic data set based on the World Hydrographic Program in the 1990s (Key et al., 2004), and is now suitable for accurate assessments of, for example, oceanic carbon inventories and uptake rates and for model validation.

Description: The original goal of the CARINA (Carbon in Atlantic Ocean) data synthesis project was to create a merged calibrated data set from open ocean subsurface measurements by European scientists that would be generally useful for biogeochemical investigations in the North Atlantic and in particular, studies involving the carbon system. Over time the geographic extent expanded to include the entire Atlantic, the Arctic and the Southern Ocean and the international collaboration broadened significantly. In this paper we give a brief history of the project, a general overview of data included and an outline of the procedures used during the synthesis. The end result of this project was a set of 3 data products, one for each of the listed ocean regions. It is critical that anyone who uses any of the CARINA data products recognize that the data products are not simply concatenations of the originally measured values. Rather, the data have been through an extensive calibration procedure designed to remove measurement bias and bad data. Also a significant fraction of the individual values in the data products were derived either by direct calculation or some means of approximation. These data products were constructed for basin scale biogeochemical investigations and may be inappropriate for investigations involving small areal extent or similar detailed analyses. More information on specific parts of this project can be found in companion articles in this issue. In particular, Tanhua et al. (2009) and Tanhua (2009) describe the procedures and software used to remove measurement bias from the original data. The three data products and a significant volume of supporting information are available from the CARINA web site hosted by the Carbon Dioxide Information Analysis Center (CDIAC: http://cdiac.esd.ornl.gov/oceans/CARINA/Carina_inv.html). Anyone wanting to use the data is advised to get the highest version number of each data product. Incremental versions represent either corrections or additions. The web site documents specifics of the changes.