An ocean current inversion accuracy analysis based on a Doppler spectrum model

BAO Qingliu; ZHANG Youguang; LIN Mingsen; GONG Peng

doi:10.1007/s13131-017-1115-y

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Article Navigation > Acta Oceanologica Sinica > 2017 > 36(9): 101-107

BAO Qingliu, ZHANG Youguang, LIN Mingsen, GONG Peng. An ocean current inversion accuracy analysis based on a Doppler spectrum model[J]. Acta Oceanologica Sinica, 2017, 36(9): 101-107. doi: 10.1007/s13131-017-1115-y

Citation:

BAO Qingliu, ZHANG Youguang, LIN Mingsen, GONG Peng. An ocean current inversion accuracy analysis based on a Doppler spectrum model[J]. Acta Oceanologica Sinica, 2017, 36(9): 101-107. doi: 10.1007/s13131-017-1115-y

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An ocean current inversion accuracy analysis based on a Doppler spectrum model

doi: 10.1007/s13131-017-1115-y

1.
Key Laboratory of State Oceanic Administration for Space Ocean Remote Sensing and Application, National Satellite Ocean Application Service, State Oceanic Administration, Beijing 100081, China;Key Laboratory of Ministry of Education for Earth System Modeling, Department of Earth System Science, Tsinghua University, Beijing 100084, China
2.
Key Laboratory of State Oceanic Administration for Space Ocean Remote Sensing and Application, National Satellite Ocean Application Service, State Oceanic Administration, Beijing 100081, China
3.
Key Laboratory of Ministry of Education for Earth System Modeling, Department of Earth System Science, Tsinghua University, Beijing 100084, China

Received Date: 2016-04-05

Abstract

Abstract

Microwave remote sensing is one of the most useful methods for observing the ocean parameters. The Doppler frequency or interferometric phase of the radar echoes can be used for an ocean surface current speed retrieval, which is widely used in spaceborne and airborne radars. While the effect of the ocean currents and waves is interactional. It is impossible to retrieve the ocean surface current speed from Doppler frequency shift directly. In order to study the relationship between the ocean surface current speed and the Doppler frequency shift, a numerical ocean surface Doppler spectrum model is established and validated with a reference. The input parameters of ocean Doppler spectrum include an ocean wave elevation model, a directional distribution function, and wind speed and direction. The suitable ocean wave elevation spectrum and the directional distribution function are selected by comparing the ocean Doppler spectrum in C band with an empirical geophysical model function (CDOP). What is more, the error sensitivities of ocean surface current speed to the wind speed and direction are analyzed. All these simulations are in Ku band. The simulation results show that the ocean surface current speed error is sensitive to the wind speed and direction errors. With VV polarization, the ocean surface current speed error is about 0.15 m/s when the wind speed error is 2 m/s, and the ocean surface current speed error is smaller than 0.3 m/s when the wind direction error is within 20° in the cross wind direction.
- Doppler spectrum model,
- ocean surface current speed,
- parameter sensitivity analysis,
- measurement error

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References(14)

References

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