Sensitivity Analysis of Ocean Microwave Radiation Characteristics

Abstract:

Ocean salinity is one of the important parameters in marine ecosystem and climate system. Satellite-borne microwave radiometer observing system is the only feasible method to study the distributions and changes of the global ocean salinity. Numbers of factors make a great impact on the sea salinity inversion accuracy based on the microwave radiation technology. These factors include the sea surface temperature, distribution range of the salinity, the observation angle, polarization, as well as the microwave frequency of the microwave radiometer. The present paper analyzed the effect of microwave frequency, incidence angle and polarization mode on the sensitivity of the ocean salinity based on the microwave radiation simulated data of calm see surface. Furthermore, it studied the effect of the seawater temperature and salinity distributions on the salinity sensitivity. The results indicated that the sensitivity between the ocean surface microwave radiation and the water salinity decreased with increased microwave frequency; the influence of the incident angle on the sensitivity is related to the polarization mode. The sensitivity increased with the increasing of the incident angle under V-polarization mode, however, the sensitivity decreased under H-polarization mode. The water temperature had an effect of amplification on the sensitivity. The higher the temperature of water is, the stronger the sensitivity is. However, the changing trend of the sensitivity was not related with the polarization, frequency, and incident angle.

• Periodical: Advanced Materials Research (Volumes 726-731)
• Pages: 4718-4722
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.726-731.4718
• Online since: August 2013
• Authors: Bu He Wu*, Xiao Yao Wang, Hong Zhang Ma, Shu Guang Li
• Keywords: Emissivity, Incident Angle, Microwave Frequency, Salinity, Temperature Range

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