Electrical conductivity of the global ocean
Robert H Tyler1,2, Tim P Boyer3, Takuto Minami4
11Geodesy and Geophysics Laboratory, Code 61A, NASA Goddard Space Flight Center, Greenbelt, MD 20771 USA.
Earth, Planets, and Space : EPS
|February 4, 2020
Summary
This study presents the first global ocean conductivity dataset derived from temperature and salinity. This crucial data supports Earth System electrodynamics, remote sensing, and oceanographic research.
Area of Science:
- Geophysics and Oceanography
- Earth System Science
- Electrodynamics
Background:
- Ocean electrical conductivity is a fundamental Earth System parameter.
- It is vital for applications including in situ flow meter calibration and remote sensing.
- Existing data lacked a comprehensive, globally gridded conductivity climatology.
Purpose of the Study:
- To provide the first globally gridded, three-dimensional ocean conductivity dataset.
- To characterize the mean conductivity and its seasonal variations.
- To offer a standard reference dataset for ocean electrodynamics and remote sensing.
Main Methods:
- Calculated ocean conductivity directly from observed temperature and salinity measurements.
- Generated a globally gridded dataset including mean, seasonal, and statistical variations.
- Utilized data relevant to satellite missions like Swarm.
Main Results:
- A comprehensive "climatology" dataset of ocean electrical conductivity has been generated.
- The dataset details global, three-dimensional mean conductivity and seasonal variations.
- Statistics of spatial and seasonal conductivity variations are presented.
Conclusions:
- The new ocean conductivity dataset serves as a vital reference for Earth System science.
- It enables improved calibration of oceanographic instruments and remote sensing techniques.
- This climatology advances our understanding of ocean electrodynamics and global processes.
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