Sea surface wind speed and sea state retrievals from dual-frequency altimeter and its preliminary application in global view of wind-sea and swell distributions

Li, Shuiqing; Shen, Hui; Hou, Yijun; He, Yijun; Fan, Bin

doi:10.1080/01431161.2018.1433889

Cited by 7 publications

(5 citation statements)

References 49 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Some altimeters, such as TOPEX, Jason-1/2/3, HY-2A, and Sentinel-3A, use the Ku-and-C dual-frequency setup, which can also be used to improve U10 accuracy [27]. A recent study showed that the difference between the RCS of the two bands is related to ocean wave information [28]. Therefore, further study can also be made to investigate whether this wave correction is redundant for the dual-frequency U10-retrieving approach.…”

Section: Discussionmentioning

confidence: 99%

Improving Altimeter Wind Speed Retrievals Using Ocean Wave Parameters

Jiang

Zheng

2020

IEEE J. Sel. Top. Appl. Earth Observations Remote Sensing

View full text Add to dashboard Cite

Spaceborne altimeters are an important data source for obtaining global sea surface wind speeds (U10). Although many altimeter U10 algorithms have been proposed and they perform well, there is still room for improvement. In this study, the data from ten altimeters were collocated with buoys to investigate the error of the altimeter U10 retrievals. The U10 residuals were found to be significantly dependent on many oceanic and atmospheric parameters. Because these oceanic and atmospheric parameters are intercorrelated, an asymptotic strategy was used to isolate the impact of different parameters and establish a neural-networkbased correction model of altimeter U10. The results indicated that significant wave heights and mean wave periods are effective in correcting U10 retrievals, probably due to the tilting modulation of long-waves on the sea surface. After the wave correction, the rootmean-square error between the U10 from altimeters and buoys was reduced from 1.45 to 1.24 m/s and the impacts of thermodynamic parameters, such as sea surface (air) temperate, became negligible. The U10 residuals after correction showed that the atmospheric instability can lead to errors on extrapolated buoy U10. The buoy measurements with large air-sea temperature differences need to be excluded in the Cal/Val of remotely sensed U10.

show abstract

Section: Discussionmentioning

confidence: 99%

Improving Altimeter Wind Speed Retrievals Using Ocean Wave Parameters

Jiang

Zheng

2020

IEEE J. Sel. Top. Appl. Earth Observations Remote Sensing

View full text Add to dashboard Cite

show abstract

“…Some altimeters, such as TOPEX, Jason-1/2/3, HY-2A, and Sentinel-3A, use the Ku-and-C dual-frequency setup, which can also be used to improve U10 accuracy [28]. A recent study showed that the difference between the RCS of the two bands is related to ocean wave information [29]. Therefore, further study can also be made to investigate whether this wave correction is redundant for the dual-frequency U10-retrieving approach.…”

Section: Discussionmentioning

confidence: 99%

Improving Altimeter Wind Speed Retrievals Using Ocean Wave Parameters

Jiang¹,

Zheng²,

Mu³

2020

Preprint

View full text Add to dashboard Cite

Spaceborne altimeters are an important data source for obtaining global sea surface wind speeds (U10). Although many altimeter U10 algorithms have been proposed and they perform well, there is still room for improvement. In this study, the data from ten altimeters were collocated with buoys to investigate the error of the altimeter U10 retrievals. The U10 residuals were found to be significantly dependent on many oceanic and atmospheric parameters. Because these oceanic and atmospheric parameters are inter-correlated, an asymptotic strategy was used to isolate the impact of different parameters and establish a neural-network-based correction model of altimeter U10. The results indicated that significant wave heights and mean wave periods are effective in correcting U10 retrievals, probably due to the tilting modulation of long-waves on the sea surface. After the wave correction, the root-mean-square error of the retrieved U10 was reduced from 1.42 m/s to 1.24 m/s and the impacts of thermodynamic parameters, such as sea surface (air) temperate, became negligible. The U10 residuals after correction showed that the atmospheric instability can lead to errors on extrapolated buoy U10. The buoy measurements with large air-sea temperature differences need to be excluded in the Cal/Val of remotely sensed U10.

show abstract

“…To improve the wind speed inversion accuracy, SWH is usually introduced into the model function [18], [51]. For SWIM, the model function for retrieving wind speed (U 10 ) can be expressed as:…”

Section: Wind Speed Inversionmentioning

confidence: 99%

A New Cyclic Iterative Correction Algorithm for Retrieving Sea Surface Wind Speed Based on a Multilayer-Medium Model

Tian

Shi

2022

IEEE Access

View full text Add to dashboard Cite

At high sea conditions, e.g., typhoons and hurricanes, the sea surface waves break and produce foams, spray droplets, and bubbles, which are collectively known as whitecaps. Whitecaps covering the rough sea surface greatly absorb the electromagnetic pulses emitted by satellite remote sensors, such as altimeters, scatter-meters, and the Surface Waves Investigation and Monitoring (SWIM). Thus, the whitecaps reduce the sea surface backscattering, which results in the sea surface wind speed being overestimated, an error that is particularly prevalent at high wind speeds. Many algorithms of retrieving wind speeds can retrieve effectively sea surface wind speed when the wind speed is less than 15m/s, but the bias of retrieving wind speed is become bigger and bigger when wind speed is more than 20m/s. In order to eliminate the effect of whitecaps on retrieving the sea surface wind speed at high wind speeds(>15m/s), we propose a Cyclic Iterative Correction Algorithm(CICA). Firstly, a four-layer medium with including whitecaps is established. Secondly, the effect of whitecaps is calculated. Finally, the retrieving and correcting wind speed is continuously repeated. The ultimate goal is to remove the whitecaps' influence on the backscattering coefficient and re-correct the overestimated wind speed until it reaches a constant value. The wind speeds measured by SWIM were corrected by using CICA, and then were compared with buoy measurements. Those comparisons show that using CICA can improve the wind speed inversion accuracy to 1.5 m/s, an improvement that is particularly evident in high sea conditions.

show abstract

Sea surface wind speed and sea state retrievals from dual-frequency altimeter and its preliminary application in global view of wind-sea and swell distributions

Cited by 7 publications

References 49 publications

Improving Altimeter Wind Speed Retrievals Using Ocean Wave Parameters

Improving Altimeter Wind Speed Retrievals Using Ocean Wave Parameters

Improving Altimeter Wind Speed Retrievals Using Ocean Wave Parameters

A New Cyclic Iterative Correction Algorithm for Retrieving Sea Surface Wind Speed Based on a Multilayer-Medium Model

Contact Info

Product

Resources

About