Wind speed inversion and in-orbit assessment of the imaging altimeter on Tiangong-2 space station

Youguang Zhang; Qingliu Bao; Mingsen Lin; Shuyan Lang

doi:10.1007/s13131-020-1687-9

Volume 39 Issue 12

Jan. 2021

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Youguang Zhang, Qingliu Bao, Mingsen Lin, Shuyan Lang. Wind speed inversion and in-orbit assessment of the imaging altimeter on Tiangong-2 space station[J]. Acta Oceanologica Sinica, 2020, 39(12): 114-120. doi: 10.1007/s13131-020-1687-9

Citation:

Youguang Zhang, Qingliu Bao, Mingsen Lin, Shuyan Lang. Wind speed inversion and in-orbit assessment of the imaging altimeter on Tiangong-2 space station[J]. Acta Oceanologica Sinica, 2020, 39(12): 114-120. doi: 10.1007/s13131-020-1687-9

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Wind speed inversion and in-orbit assessment of the imaging altimeter on Tiangong-2 space station

doi: 10.1007/s13131-020-1687-9

1.
Key Laboratory of Space Ocean Remote Sensing and Application, National Satellite Ocean Application Service, Beijing 100081, China
2.
Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China
3.
Beijing Piesat Information Technology Co., Ltd., Beijing 100195, China

Funds: The National Key Research and Development Program of China under contract No. 2016YFC1401002; the Key Special Project for Introduced Talents Team of Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou) under contract No. GML2019ZD0302; the National Natural Science Foundation of China under contract No. 41606202.

More Information

Corresponding author: E-mail: baoqingliu@piesat.cn
Received Date: 2019-07-01
Accepted Date: 2019-12-17

Available Online: 2021-04-21

Publish Date: 2020-12-25

Abstract

Abstract

Imaging altimeter (IALT) is a new type of radar altimeter system. In contrast to the conventional nadir-looking altimeters, such as HY-2A altimeter, Jason-1/2, and TOPEX/Poseidon, IALT observes the earth surface at low incident angles (2.5°–8°), so its swath is much wider and its spatial resolution is much higher than the previous altimeters. This paper presents a wind speed inversion method for the recently launched IALT onboard Tiangong-2 space station. Since the current calibration results of IALT do not agree well with the well-known wind geophysical model function at low incidence angles, a neural network is used to retrieve the ocean surface wind speed in this study. The wind speed inversion accuracy is evaluated by comparing with the ECMWF reanalysis wind speed, buoy wind speed, and in-situ ship measurements. The results show that the retrieved wind speed bias is about –0.21 m/s, and the root-mean-square (RMS) error is about 1.85 m/s. The wind speed accuracy of IALT meets the performance requirement.
- imaging altimeter,
- ocean surface wind speed,
- inversion accuracy analysis,
- in-orbit assessment

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References(19)

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