Oceanography The Official Magazine of
The Oceanography Society
Volume 32 Issue 02

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Volume 32, No. 2
Pages 50 - 57

Deployment of the SEA-POL C-band Polarimetric Radar to SPURS-2

Steven A. Rutledge V. ChandrasekarBrody FuchsJim GeorgeFrancesc JunyentPatrick KennedyBrenda Dolan
Article Abstract

As part of the Salinity Processes in the Upper-ocean Regional Study (SPURS-2) 2017 cruise to the eastern tropical Pacific, the Colorado State University SEA-POL (SEA-going POLarimetric) C-band radar made its first ever ship deployment. Previous ship-based experiments have used Doppler radars to map rainfall and the structure of oceanic convection, but SPURS-2 marked the first time the US research community deployed a dual-polarimetric radar at sea. Dual-polarimetric radar transmits and receives electromagnetic radiation in both horizontal (H) and vertical (V) polarizations simultaneously and thereby makes additional, important measurements of precipitation compared to a single polarization radar, which normally transmits horizontal polarization only. For H-polarization, the electric field vector of the transmit pulse is horizontal to the local Earth’s surface; for V-polarization, the electric field vector is perpendicular to Earth’s surface. Polarization measurements provide information about particle size, shape, and phase (water vs. ice). As a result, superior rain rate estimates are afforded by the dual-polarimetric technology. During SPURS-2, SEA-POL produced rain maps in real time to locate freshwater lenses forming on the ocean’s surface to develop context for oceanographic measurements of surface temperature and salinity.


Rutledge, S.A., V. Chandrasekar, B. Fuchs, J. George, F. Junyent, P. Kennedy, and B. Dolan. 2019. Deployment of the SEA-POL C-band polarimetric radar to SPURS-2. Oceanography 32(2):50–57, https://doi.org/10.5670/oceanog.2019.212.


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