| Contributors | Affiliation | Role |
|---|---|---|
| Takahashi, Taro | Lamont-Doherty Earth Observatory (LDEO) | Principal Investigator |
| Sutherland, Stewart C. | Lamont-Doherty Earth Observatory (LDEO) | Contact |
| Copley, Nancy | Woods Hole Oceanographic Institution (WHOI BCO-DMO) | BCO-DMO Data Manager |
This dataset was assembled for the purpose of testing the mutual consistency of the TA-TCO2-pCO2 observations in surface ocean water using an inorganic carbon chemistry model.
The potential alkalinity-salinity relationships in 33 oceanic regions were obtained using this datasat. These relationships were used to map the distribution of the total alkalinity (= potential alkalinity - nitrate concentration) over the global oceans.
Associated dataset: LDEO surface gridded carbon parameters.
Maps of global estimated pH
Carbon-nutrient database assembled from the GLODAP, CARINA and LDEO data sets for surface ocean.
| File |
|---|
pH_obs_bydate.csv (Comma Separated Values (.csv), 1.54 MB) MD5:fc7dcd5eff2a4aa6e924ecdf2fc62c39 Primary data file for dataset ID 3963 |
| Parameter | Description | Units |
| lat | Latitude; North is positive | decimal degrees |
| lon | Longitude; East is positive | decimal degrees |
| day | Day of the month | unitless |
| month | Month of the year (Jan = 1 Feb = 2 etc.) | unitless |
| year | Calendar year | unitless |
| press | Pressure | decibars |
| temp | Temperature | degrees Celsius |
| sal | Salinity (Practical Salinity Scale) | unitless |
| O2_umol_kg | dissolved Oxygen | micromoles per kilogram seawater |
| NO3 | Nitrate | micromoles per kilogram seawater |
| NO2 | Nitrite | micromoles per kilogram seawater |
| SiO3 | Silicate | micromoles per kilogram seawater |
| PO4 | Phosphate | micromoles per kilogram seawater |
| Freon_11 | Freon 11 | picomoles per kilogram seawater |
| Freon_12 | Freon 12 | picomoles per kilogram seawater |
| TCO2_kg | Observed Total CO2 | micromoles per kilogram seawater |
| TALK | Observed Total Alkalinity | microequivalents per kilogram seawater |
| PCO2 | Observed Partial Pressure of CO2 at temp_PCO2 temperature | microatmospheres |
| temp_PCO2 | Temperature at which pCO2 was measured | degrees Celsius |
| PCO2_sst | Partial Pressure of CO2 at seawater temperature | microatmospheres |
| Website | |
| Platform | LDEO |
| Start Date | 2011-01-01 |
| End Date | 2013-12-31 |
In this project, researchers at the Lamont-Doherty Earth Observatory of Columbia University will obtain the global distribution of surface ocean pH in a single unified scale based on the observations for pCO2, total alkalinity and total CO2 ion concentration (DIC) in surface waters. They will utilize three decades of their own pCO2 and DIC data, which are based on David Keeling's (and successor Pieter Tans at ERL/NOAA) WMO manometric CO2 standard, and the well-calibrated alkalinity data from the WOCE program (Dickson et al., 2003) and the time-series stations including BATS, HOT and ESTOC. These data will allow establishment of a global ocean pH and carbonate concentration baseline anchored firmly to the international CO2 standards common to the atmospheric and oceanic CO2 measurements. The pCO2 and DIC data obtained in different years will be corrected to a reference year 2000, and a climatological distribution of monthly mean pH in the total hydrogen ion scale and carbonate ion concentrations will be computed using the dissociation constants for carbonic and boric acids of Lueker et al. (2000) and Dickson (1990). This will serve as a world ocean baseline distribution for the characterization of future ocean acidification. In some data-rich areas of the North Atlantic, North Pacific and Southern Ocean, the rate of change will be demonstrated.
Because of calibration problems associated with direct pH measurements, an observation-based global ocean pH distribution map is not possible; presently the information is based on ocean GCM studies without land interactions. The research team's ongoing analysis of the alkalinity data shows, however, that its distribution differs from the open oceans in the broad regions of land interactions such as in the Bay of Bengal, Arabian Sea, Gulf of Alaska and Bering Sea. This suggests that the model results are biased by the omission of rivers and land interactions. The results of our proposed investigation will be used for the validation of global biogeochemical ocean models and will help to place the global ocean acidification study on a much firmer base.
Broader Impacts: Baseline information is needed for accurate characterization of global environmental changes. The purpose of this study is to provide a global surface ocean baseline for pH and carbonate ion concentration in waters computed in a uniform pH scale using an extensive pCO2, alkalinity and DIC database obtained for past several decades. This should serve as a reference level, against which the future and past changes may be referenced.
NSF Climate Research Investment (CRI) activities that were initiated in 2010 are now included under Science, Engineering and Education for Sustainability NSF-Wide Investment (SEES). SEES is a portfolio of activities that highlights NSF's unique role in helping society address the challenge(s) of achieving sustainability. Detailed information about the SEES program is available from NSF (https://www.nsf.gov/funding/pgm_summ.jsp?pims_id=504707).
In recognition of the need for basic research concerning the nature, extent and impact of ocean acidification on oceanic environments in the past, present and future, the goal of the SEES: OA program is to understand (a) the chemistry and physical chemistry of ocean acidification; (b) how ocean acidification interacts with processes at the organismal level; and (c) how the earth system history informs our understanding of the effects of ocean acidification on the present day and future ocean.
Solicitations issued under this program:
NSF 10-530, FY 2010-FY2011
NSF 12-500, FY 2012
NSF 12-600, FY 2013
NSF 13-586, FY 2014
NSF 13-586 was the final solicitation that will be released for this program.
PI Meetings:
1st U.S. Ocean Acidification PI Meeting(March 22-24, 2011, Woods Hole, MA)
2nd U.S. Ocean Acidification PI Meeting(Sept. 18-20, 2013, Washington, DC)
3rd U.S. Ocean Acidification PI Meeting (June 9-11, 2015, Woods Hole, MA – Tentative)
NSF media releases for the Ocean Acidification Program:
Press Release 10-186 NSF Awards Grants to Study Effects of Ocean Acidification
Discovery Blue Mussels "Hang On" Along Rocky Shores: For How Long?
Press Release 13-102 World Oceans Month Brings Mixed News for Oysters
| Funding Source | Award |
|---|---|
| NSF Division of Ocean Sciences (NSF OCE) |