Following the success of WG 145 members Simon Clegg, Heather Benway, and Andrew Dickson in obtaining 3 year grants from NERC (in the UK) and NSF in the USA, we are very pleased to announce major additions to our collaboration:
- Frank Bastkowski and Steffen Seitz, of Physikalisch-Technische Bundesanstalt (PTB), Braunschweig.
- Igor Maksimov and Toshiaki Asakai, of the National Metrology Institute of Japan.
- Daniela Stoica, of the Laboratoire national de métrologie et d’essai, Paris.
- Pablo Lodeiro and Eric Achterberg, of GEOMAR (the Helmholtz Institute of Ocean Research, Kiel).
The first three groups will all be making Harned Cell measurements of HCl activities in solutions containing Tris/TrisH+ buffer, and the components of seawater (beginning with NaCl).
Pablo and Eric will be measuring salt solubilities in aqueous mixtures, to obtain values of the activities of the salts at saturation. They may also be carrying out potentiometric titrations.
The purpose of both types of experiments is to obtain the activities of dissolved species in the solutions, and so determine the parameters of the Pitzer the chemical speciation model we are developing. These parameters, whose values are functions of temperature and pressure, express the strength of interactions between pairs of cations and anions, and then triplets of ions (two ions of one sign, and one ion of opposite sign). They can only be determined by fitting to measurements.
We and proud to announce that the Natural Environment Environment Council of the UK, and the National Science Foundation in the USA, have awarded a 3 year grant to the project “NSFGEO-NERC: A Thermodynamic Chemical Speciation Model for the Oceans, Seas, and Estuaries“. The investigators on this project are WG members Simon Clegg (University of East Anglia), Andrew Dickson (Scripps Institution of Oceanography), and Heather Benway (Woods Hole Oceanographic Institution).
Model development will be carried out at UEA, and experiments (using Harned Cells and a calorimeter) at Scripps. Heather, who is the Executive Officer of NSF’s Ocean Carbon and Biogeochemistry programme, is our link to the chemical oceanography community and will ensure that our efforts meet their needs.
Our Working Group is dedicated to advancing the ability of chemical oceanographers to model chemical speciation in seawater and other natural waters. We are collaborating with a group of national metrological institutes to carry out new laboratory measurements to characterise the thermodynamic properties and speciation in the major and minor components of seawater, and in the aqueous buffers used to calibrate instruments for measuring pH. Concurrently, we are also working on an uncertainty analysis of currently available data and “Pitzer” speciation models.
The aim of the Working Group is, over a period of years, to develop a user-friendly comprehensive chemical speciation model of seawater and related natural waters. The model will include a full treatment of uncertainties. Our efforts are supported by grants from the Natural Environment Research Council in the UK, and the National Science Foundation in the USA. This Working Group is sponsored by the Scientific Committee on Oceanic Research.
On this website we describe our activities and achievements, and current activities of interest to the chemical oceanography community. For further information, please contact either David Turner (firstname.lastname@example.org), or Simon Clegg (email@example.com).