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Preliminary Study of Oceanic Eddies Detected by Tiangong-2 Interferometric Imaging Radar Altimeter

  • Yuhang Wang
  • Weiya Kong
  • Jinsong Chong
Conference paper
Part of the Lecture Notes in Electrical Engineering book series (LNEE, volume 541)

Abstract

Oceanic eddy, which plays an important role in ocean thermal cycling, is a significant branch of oceanic scientific research. Mesoscale eddies can be observed by multiple sensors. However, sub-mesoscale or small scale eddies cannot be detected by conventional radar altimeters. The Interferometric Imaging Radar Altimeter (InIRA) on Tiangong-2 provides a large amount of images for the observation and investigation of sub-mesoscale or small scale eddies. 100 InIRA images obtained during 2016–2018 are used to investigate possible mechanisms of the appearance of eddies in InIRA images. Result shows that under a moderate wind speed of 3–5 m/s, film mechanism is the main form of oceanic eddies and under a considerable near-water wind speed of 5–12 m/s, and the wave/current interaction mechanism comes into action. The interferometric data of InIRA are processed to detect eddies after a series of procedures. It is shown that the phase change is corresponding to ocean surface height anomaly induced by eddy. Moderate Resolution Imaging Spectroradiometer (MODIS) sea surface temperature (SST) and chlorophyll-a (CHL) data are used to verify eddies identified from InIRA images. Result shows that the center of eddy with lowest SST corresponds to the highest CHL concentration.

Keywords

Tiangong-2 Oceanic eddies Interferometric imaging radar altimeter Interferometric phase 

Notes

Acknowledgement

Thanks to China Manned Space Engineering for providing InIRA data products of Tiangong-2. We also thank NASA for providing MODIS SST and ocean color data products.

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Copyright information

© Springer Nature Singapore Pte Ltd. 2019

Authors and Affiliations

  1. 1.National Key Laboratory of Science and Technology on Microwave ImagingBeijingChina
  2. 2.Institute of ElectronicsChinese Academy of SciencesBeijingChina
  3. 3.School of Electronics, Electrical and Communication EngineeringUniversity of Chinese Academy of SciencesBeijingChina

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