【Title】The Thermodynamic Equation of Seawater 2010 and Its Comparison with the Equation of Seawater 1980
【Journal】Advances in Earth Sciences
Equation of seawater;
【Abstract】With the International Temperature Scale 1990 and the Absolute Salinity that accounts for the effects of the spatial variation of seawater composition around the world ocean, the new International Thermodynamic Equation of Seawater 2010 (TEOS-10) has higher accuracy and wider application scope, Compared to the Equation of Seawater 1980 (EOS-80). TEOS-10 allows the calculation of many thermodynamic quantities, such as entropy, enthalpy and heat content, that were not available from EOS-80. Therefore, TEOS-10 will make significant impacts on the development of oceanography. TEOS-10 is compared with EOS-80 based on their applications on climatological averaged data. The difference of the calculated density with these two equations reaches 10-2 kg,/m3 in most regions of the world ocean. It is particularly significant in the North Pacific Ocean, North Indian Ocean and also the deep areas in East China Sea and the South China Sea. So in these regions, this difference must be considered in the studies and applications that require high accuracy. The improvements of the new equation are mostly due to a new salinity variable, Absolute Salinity that considers the impacts of all the solutes in seawater, including the neutral solutes, which could make up the deficiency of the Practical Salinity. In order to promote the development of oceanography, the Absolute Salinity and TEOS-10 are recommended to be applied as soon as possible.