scholarly journals What drives the latitudinal gradient in open-ocean surface dissolved inorganic carbon concentration?

2019 ◽  
Vol 16 (13) ◽  
pp. 2661-2681 ◽  
Author(s):  
Yingxu Wu ◽  
Mathis P. Hain ◽  
Matthew P. Humphreys ◽  
Sue Hartman ◽  
Toby Tyrrell
Keyword(s):  
Southern Ocean ◽  
High Latitude ◽  
Latitudinal Gradient ◽  
Inorganic Carbon ◽  
Dissolved Inorganic Carbon ◽  
Latitudinal Gradients ◽  
Total Alkalinity ◽  
Global Ocean ◽  
Low Latitude ◽  
Surface Ocean

Abstract. Previous work has not led to a clear understanding of the causes of spatial pattern in global surface ocean dissolved inorganic carbon (DIC), which generally increases polewards. Here, we revisit this question by investigating the drivers of observed latitudinal gradients in surface salinity-normalized DIC (nDIC) using the Global Ocean Data Analysis Project version 2 (GLODAPv2) database. We used the database to test three different hypotheses for the driver producing the observed increase in surface nDIC from low to high latitudes. These are (1) sea surface temperature, through its effect on the CO2 system equilibrium constants, (2) salinity-related total alkalinity (TA), and (3) high-latitude upwelling of DIC- and TA-rich deep waters. We find that temperature and upwelling are the two major drivers. TA effects generally oppose the observed gradient, except where higher values are introduced in upwelled waters. Temperature-driven effects explain the majority of the surface nDIC latitudinal gradient (182 of the 223 µmol kg−1 increase from the tropics to the high-latitude Southern Ocean). Upwelling, which has not previously been considered as a major driver, additionally drives a substantial latitudinal gradient. Its immediate impact, prior to any induced air–sea CO2 exchange, is to raise Southern Ocean nDIC by 220 µmol kg−1 above the average low-latitude value. However, this immediate effect is transitory. The long-term impact of upwelling (brought about by increasing TA), which would persist even if gas exchange were to return the surface ocean to the same CO2 as without upwelling, is to increase nDIC by 74 µmol kg−1 above the low-latitude average.

scholarly journals What drives the latitudinal gradient in open ocean surface dissolved inorganic carbon concentration?

2018 ◽  
Author(s):  
Yingxu Wu ◽  
Mathis P. Hain ◽  
Matthew P. Humphreys ◽  
Sue Hartman ◽  
Toby Tyrrell
Keyword(s):  
Southern Ocean ◽  
High Latitude ◽  
Latitudinal Gradient ◽  
Equilibrium Constants ◽  
Latitudinal Gradients ◽  
Total Alkalinity ◽  
Global Ocean ◽  
Clear Understanding ◽  
Low Latitude ◽  
Surface Ocean

Abstract. Previous work has not led to a clear understanding of the causes of spatial pattern in global surface ocean DIC, which generally increases polewards. Here, we revisit this question by investigating the drivers of observed latitudinal gradients in surface salinity-normalized DIC (nDIC) using the Global Ocean Data Analysis Project Version 2 (GLODAPv2) database. We used the database to test three different hypotheses for the driver producing the observed increase in surface nDIC from low to high latitudes. These are: (1) sea surface temperature, through its effect on the CO2 system equilibrium constants, (2) salinity-related total alkalinity (TA), and (3) high latitude upwelling of DIC- and TA-rich deep waters. We find that temperature and upwelling are the two major drivers. TA effects generally oppose the observed gradient, except where higher values are introduced in upwelled waters. Temperature-driven effects explains the majority of the surface nDIC latitudinal gradient (182 out of 223 μmol kg−1 in the high-latitude Southern Ocean). Upwelling, which has not previously been considered as a major driver, additionally drives a substantial latitudinal gradient. Its immediate impact, prior to any induced air-sea CO2 exchange, is to raise Southern Ocean nDIC by 208 μmol kg−1 above the average low latitude value. However, this immediate effect is transitory. The long-term impact of upwelling (brought about by increasing TA), which would persist even if gas exchange were to return the surface ocean to the same CO2 as without upwelling, is to increase nDIC by 74 μmol kg−1 above the low latitude average.

scholarly journals Measurements of total alkalinity and inorganic dissolved carbon in the Atlantic Ocean and adjacent Southern Ocean between 2008 and 2010

2013 ◽  
Vol 6 (2) ◽  
pp. 621-639
Author(s):  
U. Schuster ◽  
A. J. Watson ◽  
D. C. E. Bakker ◽  
A. M. de Boer ◽  
E. M. Jones ◽  
...  
Keyword(s):  
Quality Control ◽  
Atlantic Ocean ◽  
Southern Ocean ◽  
Inorganic Carbon ◽  
Dissolved Inorganic Carbon ◽  
Drake Passage ◽  
Total Alkalinity ◽  
Global Ocean ◽  
Atlantic Sector ◽  
Dissolved Carbon

Abstract. Water column dissolved inorganic carbon and total alkalinity were measured during five hydrographic sections in the Atlantic Ocean and Drake Passage. The work was funded through the Strategic Funding Initiative of the UK's Oceans2025 programme, which ran from 2007 to 2012. The aims of this programme were to establish the regional budgets of natural and anthropogenic carbon in the North Atlantic, the South Atlantic, and the Atlantic sector of the Southern Ocean, as well as the rates of change of these budgets. This paper describes the dissolved inorganic carbon and total alkalinity data collected along east-west sections at 55–60° N (Arctic Gateway), 24.5° N, and 24° S in the Atlantic and across two Drake Passage sections. Other hydrographic and biogeochemical parameters were measured during these sections, yet are not covered in this paper. Over 95% of samples taken during the 24.5° N, 24° S, and the Drake Passage sections were analysed onboard and subjected to a 1st level quality control addressing technical and analytical issues. Samples taken during Arctic Gateway were analysed and subjected to quality control back in the laboratory. Complete post-cruise 2nd level quality control was performed using cross-over analysis with historical data in the vicinity of measurements, and data are available through the Carbon Dioxide Information Analysis Center (CDIAC) and are included in the Global Ocean Data Analyses Project, version 2 (GLODAP 2).

scholarly journals Measurements of total alkalinity and inorganic dissolved carbon in the Atlantic Ocean and adjacent Southern Ocean between 2008 and 2010

2014 ◽  
Vol 6 (1) ◽  
pp. 175-183 ◽  
Author(s):  
U. Schuster ◽  
A. J. Watson ◽  
D. C. E. Bakker ◽  
A. M. de Boer ◽  
E. M. Jones ◽  
...  
Keyword(s):  
Quality Control ◽  
Atlantic Ocean ◽  
Southern Ocean ◽  
Inorganic Carbon ◽  
Dissolved Inorganic Carbon ◽  
Drake Passage ◽  
Total Alkalinity ◽  
Global Ocean ◽  
Atlantic Sector ◽  
Dissolved Carbon

Abstract. Water column dissolved inorganic carbon and total alkalinity were measured during five hydrographic sections in the Atlantic Ocean and Drake Passage. The work was funded through the Strategic Funding Initiative of the UK's Oceans2025 programme, which ran from 2007 to 2012. The aims of this programme were to establish the regional budgets of natural and anthropogenic carbon in the North Atlantic, the South Atlantic, and the Atlantic sector of the Southern Ocean, as well as the rates of change of these budgets. This paper describes in detail the dissolved inorganic carbon and total alkalinity data collected along east–west sections at 47° N to 60° N, 24.5° N, and 24° S in the Atlantic and across two Drake Passage sections. Other hydrographic and biogeochemical parameters were measured during these sections, and relevant standard operating procedures are mentioned here. Over 95% of dissolved inorganic carbon and total alkalinity samples taken during the 24.5° N, 24° S, and the Drake Passage sections were analysed onboard and subjected to a first-level quality control addressing technical and analytical issues. Samples taken along 47° N to 60° N were analysed and subjected to quality control back in the laboratory. Complete post-cruise second-level quality control was performed using cross-over analysis with historical data in the vicinity of measurements, and data were submitted to the CLIVAR and Carbon Hydrographic Data Office (CCHDO), the Carbon Dioxide Information Analysis Center (CDIAC) and and will be included in the Global Ocean Data Analyses Project, version 2 (GLODAP 2), the upcoming update of Key et al. (2004).

scholarly journals Effects of eustatic sea-level change, ocean dynamics, and nutrient utilization on atmospheric <i>p</i>CO<sub>2</sub> and seawater composition over the last 130 000 years: a model study

2016 ◽  
Vol 12 (2) ◽  
pp. 339-375 ◽  
Author(s):  
K. Wallmann ◽  
B. Schneider ◽  
M. Sarnthein
Keyword(s):  
Southern Ocean ◽  
Sea Level ◽  
Ocean Circulation ◽  
Dissolved Inorganic Carbon ◽  
Nutrient Utilization ◽  
Meridional Overturning Circulation ◽  
Ocean Dynamics ◽  
Total Alkalinity ◽  
Global Ocean ◽  
Atmospheric Pco2

Abstract. We have developed and employed an Earth system model to explore the forcings of atmospheric pCO2 change and the chemical and isotopic evolution of seawater over the last glacial cycle. Concentrations of dissolved phosphorus (DP), reactive nitrogen, molecular oxygen, dissolved inorganic carbon (DIC), total alkalinity (TA), 13C-DIC, and 14C-DIC were calculated for 24 ocean boxes. The bi-directional water fluxes between these model boxes were derived from a 3-D circulation field of the modern ocean (Opa 8.2, NEMO) and tuned such that tracer distributions calculated by the box model were consistent with observational data from the modern ocean. To model the last 130 kyr, we employed records of past changes in sea-level, ocean circulation, and dust deposition. According to the model, about half of the glacial pCO2 drawdown may be attributed to marine regressions. The glacial sea-level low-stands implied steepened ocean margins, a reduced burial of particulate organic carbon, phosphorus, and neritic carbonate at the margin seafloor, a decline in benthic denitrification, and enhanced weathering of emerged shelf sediments. In turn, low-stands led to a distinct rise in the standing stocks of DIC, TA, and nutrients in the global ocean, promoted the glacial sequestration of atmospheric CO2 in the ocean, and added 13C- and 14C-depleted DIC to the ocean as recorded in benthic foraminifera signals. The other half of the glacial drop in pCO2 was linked to inferred shoaling of Atlantic meridional overturning circulation and more efficient utilization of nutrients in the Southern Ocean. The diminished ventilation of deep water in the glacial Atlantic and Southern Ocean led to significant 14C depletions with respect to the atmosphere. According to our model, the deglacial rapid and stepwise rise in atmospheric pCO2 was induced by upwelling both in the Southern Ocean and subarctic North Pacific and promoted by a drop in nutrient utilization in the Southern Ocean. The deglacial sea-level rise led to a gradual decline in nutrient, DIC, and TA stocks, a slow change due to the large size and extended residence times of dissolved chemical species in the ocean. Thus, the rapid deglacial rise in pCO2 can be explained by fast changes in ocean dynamics and nutrient utilization whereas the gradual pCO2 rise over the Holocene may be linked to the slow drop in nutrient and TA stocks that continued to promote an ongoing CO2 transfer from the ocean into the atmosphere.

scholarly journals A new global interior ocean mapped climatology: the 1° × 1° GLODAP version 2

2016 ◽  
Author(s):  
Siv K. Lauvset ◽  
Robert M. Key ◽  
Are Olsen ◽  
Steven van Heuven ◽  
Anton Velo ◽  
...  
Keyword(s):  
Inorganic Carbon ◽  
Dissolved Inorganic Carbon ◽  
Mapping Method ◽  
Total Alkalinity ◽  
The Arctic ◽  
Global Ocean ◽  
Information Analysis ◽  
Phosphate Silicate ◽  
Analysis Center ◽  
Standard Pressure

Abstract. We here present the new GLODAP version 2 (GLODAPv2) mapped climatology, which is based on data from all ocean basins up to and including 2013. In contrast to its predecessor, GLODAPv1.1, this climatology also covers the Arctic Ocean and Mediterranean Sea. The quality controlled and internally consistent data product files of GLODAPv2 (Olsen et al., 2015; Key et al., 2015) were used to create global 1° × 1° mapped climatologies of total dissolved inorganic carbon, total alkalinity, and pH using the Data-Interpolating Variational Analysis (DIVA) mapping method. Climatologies were created for 33 standard pressure surfaces. To minimize the risk of translating temporal variability in the input data to spatial variations in the mapped climatologies, layers with pressures of 1000 dbar, or less, were mapped for two different time periods: 1986–1999 and 2000–2013, roughly corresponding to the "WOCE" and "CLIVAR" eras of global ocean surveys. All data from the 1972–2013 period were used in the mapping of pressures higher than 1000 dbar. In addition to the marine CO2 chemistry parameters listed above, nitrate, phosphate, silicate, oxygen, salinity and theta were also mapped using DIVA. For these parameters all data from the full 1972–2013 period were used on all 33 surfaces. The GLODAPv2 global 1° × 1° mapped climatologies, including error fields and ancillary information have been made available at the GLODAPv2 web page at the Carbon Dioxide Information Analysis Center (CDIAC, http://cdiac.ornl.gov/oceans/GLODAPv2/).

scholarly journals CO<sub>2</sub> perturbation experiments: similarities and differences between dissolved inorganic carbon and total alkalinity manipulations

2009 ◽  
Vol 6 (2) ◽  
pp. 4441-4462 ◽  
Author(s):  
K. G. Schulz ◽  
J. Barcelos e Ramos ◽  
R. E. Zeebe ◽  
U. Riebesell
Keyword(s):  
Carbon Dioxide ◽  
Atmospheric Carbon Dioxide ◽  
Inorganic Carbon ◽  
Dissolved Inorganic Carbon ◽  
Total Alkalinity ◽  
Carbonate Chemistry ◽  
Surface Ocean ◽  
Seawater Carbonate Chemistry ◽  
Similarities And Differences ◽  
Carbon Dioxide Co2

Abstract. Increasing atmospheric carbon dioxide (CO2) through human activities and invasion of anthropogenic CO2 into the surface ocean alters the seawater carbonate chemistry, increasing CO2 and bicarbonate (HCO3

scholarly journals GLODAPv2.2019 – an update of GLODAPv2

2019 ◽  
Vol 11 (3) ◽  
pp. 1437-1461 ◽  
Author(s):  
Are Olsen ◽  
Nico Lange ◽  
Robert M. Key ◽  
Toste Tanhua ◽  
Marta Álvarez ◽  
...  
Keyword(s):  
Quality Control ◽  
Water Samples ◽  
Inorganic Carbon ◽  
Dissolved Inorganic Carbon ◽  
Total Alkalinity ◽  
The Arctic ◽  
Global Ocean ◽  
Systematic Evaluation ◽  
Isotopic Tracers ◽  
Data Product

Abstract. The Global Ocean Data Analysis Project (GLODAP) is a synthesis effort providing regular compilations of surface to bottom ocean biogeochemical data, with an emphasis on seawater inorganic carbon chemistry and related variables determined through chemical analysis of water samples. This update of GLODAPv2, v2.2019, adds data from 116 cruises to the previous version, extending its coverage in time from 2013 to 2017, while also adding some data from prior years. GLODAPv2.2019 includes measurements from more than 1.1 million water samples from the global oceans collected on 840 cruises. The data for the 12 GLODAP core variables (salinity, oxygen, nitrate, silicate, phosphate, dissolved inorganic carbon, total alkalinity, pH, CFC-11, CFC-12, CFC-113, and CCl4) have undergone extensive quality control, especially systematic evaluation of bias. The data are available in two formats: (i) as submitted by the data originator but updated to WOCE exchange format and (ii) as a merged data product with adjustments applied to minimize bias. These adjustments were derived by comparing the data from the 116 new cruises with the data from the 724 quality-controlled cruises of the GLODAPv2 data product. They correct for errors related to measurement, calibration, and data handling practices, taking into account any known or likely time trends or variations. The compiled and adjusted data product is believed to be consistent to better than 0.005 in salinity, 1 % in oxygen, 2 % in nitrate, 2 % in silicate, 2 % in phosphate, 4 µmol kg−1 in dissolved inorganic carbon, 4 µmol kg−1 in total alkalinity, 0.01–0.02 in pH, and 5 % in the halogenated transient tracers. The compilation also includes data for several other variables, such as isotopic tracers. These were not subjected to bias comparison or adjustments. The original data, their documentation and DOI codes are available in the Ocean Carbon Data System of NOAA NCEI (https://www.nodc.noaa.gov/ocads/oceans/GLODAPv2_2019/, last access: 17 September 2019). This site also provides access to the merged data product, which is provided as a single global file and as four regional ones – the Arctic, Atlantic, Indian, and Pacific oceans – under https://doi.org/10.25921/xnme-wr20 (Olsen et al., 2019). The product files also include significant ancillary and approximated data. These were obtained by interpolation of, or calculation from, measured data. This paper documents the GLODAPv2.2019 methods and provides a broad overview of the secondary quality control procedures and results.

scholarly journals An updated version of the global interior ocean biogeochemical data product, GLODAPv2.2021

2021 ◽  
Vol 13 (12) ◽  
pp. 5565-5589
Author(s):  
Siv K. Lauvset ◽  
Nico Lange ◽  
Toste Tanhua ◽  
Henry C. Bittig ◽  
Are Olsen ◽  
...  
Keyword(s):  
Quality Control ◽  
Inorganic Carbon ◽  
Dissolved Inorganic Carbon ◽  
Data System ◽  
Total Alkalinity ◽  
The Arctic ◽  
Global Ocean ◽  
Isotopic Tracers ◽  
Data Product ◽  
Ocean Carbon

Abstract. The Global Ocean Data Analysis Project (GLODAP) is a synthesis effort providing regular compilations of surface-to-bottom ocean biogeochemical bottle data, with an emphasis on seawater inorganic carbon chemistry and related variables determined through chemical analysis of seawater samples. GLODAPv2.2021 is an update of the previous version, GLODAPv2.2020 (Olsen et al., 2020). The major changes are as follows: data from 43 new cruises were added, data coverage was extended until 2020, all data with missing temperatures were removed, and a digital object identifier (DOI) was included for each cruise in the product files. In addition, a number of minor corrections to GLODAPv2.2020 data were performed. GLODAPv2.2021 includes measurements from more than 1.3 million water samples from the global oceans collected on 989 cruises. The data for the 12 GLODAP core variables (salinity, oxygen, nitrate, silicate, phosphate, dissolved inorganic carbon, total alkalinity, pH, CFC-11, CFC-12, CFC-113, and CCl4) have undergone extensive quality control with a focus on systematic evaluation of bias. The data are available in two formats: (i) as submitted by the data originator but updated to World Ocean Circulation Experiment (WOCE) exchange format and (ii) as a merged data product with adjustments applied to minimize bias. For this annual update, adjustments for the 43 new cruises were derived by comparing those data with the data from the 946 quality controlled cruises in the GLODAPv2.2020 data product using crossover analysis. Comparisons to estimates of nutrients and ocean CO2 chemistry based on empirical algorithms provided additional context for adjustment decisions in this version. The adjustments are intended to remove potential biases from errors related to measurement, calibration, and data handling practices without removing known or likely time trends or variations in the variables evaluated. The compiled and adjusted data product is believed to be consistent with to better than 0.005 in salinity, 1 % in oxygen, 2 % in nitrate, 2 % in silicate, 2 % in phosphate, 4 µmol kg−1 in dissolved inorganic carbon, 4 µmol kg−1 in total alkalinity, 0.01–0.02 in pH (depending on region), and 5 % in the halogenated transient tracers. The other variables included in the compilation, such as isotopic tracers and discrete CO2 fugacity (fCO2), were not subjected to bias comparison or adjustments. The original data, their documentation, and DOI codes are available at the Ocean Carbon Data System of NOAA NCEI (https://www.ncei.noaa.gov/access/ocean-carbon-data-system/oceans/GLODAPv2_2021/, last access: 7 July 2021). This site also provides access to the merged data product, which is provided as a single global file and as four regional ones – the Arctic, Atlantic, Indian, and Pacific oceans – under https://doi.org/10.25921/ttgq-n825 (Lauvset et al., 2021). These bias-adjusted product files also include significant ancillary and approximated data and can be accessed via https://www.glodap.info (last access: 29 June 2021). These were obtained by interpolation of, or calculation from, measured data. This living data update documents the GLODAPv2.2021 methods and provides a broad overview of the secondary quality control procedures and results.

scholarly journals Enhance Ocean Carbon Observations: Successful Implementation of a Novel Autonomous Total Alkalinity Analyzer on a Ship of Opportunity

2020 ◽  
Vol 7 ◽  
Author(s):  
Katharina Seelmann ◽  
Tobias Steinhoff ◽  
Steffen Aßmann ◽  
Arne Körtzinger
Keyword(s):  
Large Volume ◽  
Polyvinylidene Fluoride ◽  
Inorganic Carbon ◽  
Dissolved Inorganic Carbon ◽  
Total Alkalinity ◽  
Spatiotemporal Variability ◽  
Global Ocean ◽  
Observation System ◽  
Successful Implementation ◽  
Ocean Carbon

Over recent decades, observations based on merchant vessels (Ships of Opportunity—SOOP) equipped with sensors measuring the CO2 partial pressure (pCO2) in the surface seawater formed the backbone of the global ocean carbon observation system. However, the restriction to pCO2 measurements alone is one severe shortcoming of the current SOOP observatory. Full insight into the marine inorganic carbon system requires the measurement of at least two of the four measurable variables which are pCO2, total alkalinity (TA), dissolved inorganic carbon (DIC), and pH. One workaround is to estimate TA values based on established temperature-salinity parameterizations, but this leads to higher uncertainties and the possibility of regional and/or seasonal biases. Therefore, autonomous SOOP-based TA measurements are of great interest. Our study describes the implementation of a novel autonomous analyzer for seawater TA, the CONTROS HydroFIAⓇ TA system (-4H-JENA engineering GmbH, Germany) for unattended routine TA measurements on a SOOP line operating in the North Atlantic. We present the installation in detail and address major issues encountered with autonomous measurements using this analyzer, e.g., automated cleaning and stabilization routines, and waste handling. Another issue during long-term deployments is the provision of reference seawater in large-volume containers for quality assurance measurements and drift correction. Hence, a stable large-volume seawater storage had to be found. We tested several container types with respect to their suitability to store seawater over a time period of 30 days without significant changes in TA. Only one gas sampling bag made of polyvinylidene fluoride (PVDF) satisfied the high stability requirement. In order to prove the performance of the entire setup, we compared the autonomous TA measurements with TA from discrete samples taken during the first two trans-Atlantic crossings. Although the measurement accuracy in unattended mode (about ± 5 μmol kg^-1) slightly deteriorated compared to our previous system characterization, its overall uncertainty fulfilled requirements for autonomous TA measurements on SOOP lines. A comparison with predicted TA values based on an established and often used parameterization pointed at regional and seasonal limitations of such TA predictions. Consequently, TA observations with better coverage of spatiotemporal variability are needed, which is now possible with the method described here.

scholarly journals OceanSODA-ETHZ: A global gridded data set of the surface ocean carbonate system for seasonal to decadal studies of ocean acidification

2020 ◽  
Author(s):  
Luke Gregor ◽  
Nicolas Gruber
Keyword(s):  
Ocean Acidification ◽  
Dissolved Inorganic Carbon ◽  
Total Error ◽  
Total Alkalinity ◽  
Global Ocean ◽  
Carbonate System ◽  
Data Set ◽  
Saturation State ◽  
Mean Squared Errors ◽  
Surface Ocean

Abstract. Ocean acidification has altered the ocean's carbonate chemistry profoundly since preindustrial times, with potentially serious consequences for marine life. Yet, no long-term global observation-based data set exists that permits to study changes in ocean acidification for all carbonate system parameters over the last few decades. Here, we fill this gap and present a methodologically consistent global data set of all relevant surface ocean parameters, i.e., dissolved inorganic carbon (DIC), total alkalinity (TA), partial pressure of CO2 (pCO2), pH, and the saturation state with respect to mineral CaCO3 (Ω) at monthly resolution over the period 1985 through 2018 at a spatial resolution of 1 × 1°. This data set, named OceanSODA-ETHZ, was created by extrapolating in time and space the surface ocean observations of pCO2 (from the Surface Ocean CO2 ATlas (SOCAT)) and total alkalinity (TA, from the Global Ocean Data Analysis Project (GLODAP)) using the newly developed Geospatial Random Cluster Ensemble Regression (GRaCER) method. This method is based on a two-step (cluster-regression) approach, but extends it by considering an ensemble of such cluster-regressions, leading to higher robustness. Surface ocean DIC, pH, and Ω were then computed from the globally mapped pCO2 and TA using the thermodynamic equations of the carbonate system. For the open ocean, the cluster regression method estimates pCO2 and TA with global near-zero biases and root mean squared errors of 12 µatm and 13 µmol kg−1, respectively. Taking into account also the measurement and representation errors, the total error increases to 14 µatm and 21 µmol kg−1, respectively. We assess the fidelity of the computed parameters by comparing them to direct observations from GLODAP, finding surface ocean pH and DIC global biases of near zero, and root mean squared errors of 0.023 and 16 µmol kg−1, respectively. These errors are very comparable to those expected by propagating the total errors from pCO2 and TA through the thermodynamic computations, indicating a robust and conservative assessment of the errors. We illustrate the potential of this new dataset by analyzing the climatological mean seasonal cycles of the different parameters of the surface ocean carbonate system, highlighting their commonalities and differences. The OceanSODA-ETHZ data can be downloaded from https://doi.org/10.25921/m5wx-ja34 (Gregor and Gruber, 2020).

Sign in / Sign up

Export Citation Format

Share Document