Coastal wind field retrieval from polarimetric synthetic aperture radar

来源 :Acta Oceanologica Sinica | 被引量 : 0次 | 上传用户:qiaotongqiao
下载到本地 , 更方便阅读
声明 : 本文档内容版权归属内容提供方 , 如果您对本文有版权争议 , 可与客服联系进行内容授权或下架
论文部分内容阅读
Coastal winds are strongly influenced by topology and discontinuity between land and sea surfaces. Wind assessment from remote sensing in such a complex area remains a challenge. Space-borne scatterometer does not provide any information about the coastal wind field, as the coarse spatial resolution hampers the radar backscattering. Synthetic aperture radar(SAR) with a high spatial resolution and all-weather observation abilities has become one of the most important tools for ocean wind retrieval, especially in the coastal area. Conventional methods of wind field retrieval from SAR, however, require wind direction as initial information, such as the wind direction from numerical weather prediction models(NWP), which may not match the time of SAR image acquiring. Fortunately, the polarimetric observations of SAR enable independent wind retrieval from SAR images alone. In order to accurately measure coastal wind fields, this paper proposes a new method of using co-polarization backscattering coefficients from polarimetric SAR observations up to polarimetric correlation backscattering coefficients, which are acquired from the conjugate product of co-polarization backscatter and cross-polarization backscatter. Co-polarization backscattering coefficients and polarimetric correlation backscattering coefficients are obtained form Radarsat-2 single-look complex(SLC) data.The maximum likelihood estimation is used to gain the initial results followed by the coarse spatial filtering and fine spatial filtering. Wind direction accuracy of the final inversion results is 10.67 with a wind speed accuracy of 0.32 m/s. Unlike previous methods, the methods described in this article utilize the SAR data itself to obtain the wind vectors and do not need external wind directional information. High spatial resolution and high accuracy are the most important features of the method described herein since the use of full polarimetric observations contains more information about the space measured.This article is a useful addition to the work of independent SAR wind retrieval. The experimental results herein show that it is feasible to employ the co-polarimetric backscattering coefficients and the polarimetric correlation backscattering coefficients for coastal wind field retrieval. Coastal winds are strongly affected by topology and discontinuity between land and sea surfaces. Wind assessment from remote sensing in such a complex area remains a challenge. Space-borne scatterometer does not provide any information about the coastal wind field, as the coarse spatial resolution hampers The radar backscattering. Synthetic aperture radar (SAR) with a high spatial resolution and all-weather observation abilities has become one of the most important tools for ocean wind retrieval, especially in the coastal area. Conventional methods of wind field retrieval from SAR, however , require wind direction as initial information, such as the wind direction from numerical weather prediction models (NWP), which may not match the time of SAR image acquired. Fortunately, the polarimetric observations of SAR enable independent wind retrieval from SAR images alone. In order to accurately measure coastal wind fields, this paper proposes a new method of using co-polarization backscatte ring coefficients from polarimetric SAR observations up to polarimetric correlation backscattering coefficients, which are acquired from the conjugate product of co-polarization backscatter and cross-polarization backscatter. Co-polarization backscattering coefficients and polarimetric correlation backscattering coefficients are obtained form Radarsat-2 single-look complex (SLC) data.The maximum likelihood estimation is used to gain the initial results followed by the coarse spatial filtering and fine spatial filtering. Wind direction accuracy of the final inversion results is 10.67 with a wind speed accuracy of 0.32 m / s. previous methods, the methods described in this article utilize the SAR data itself to obtain the wind vectors and do not need external wind directional information. observations contains more information about the space measured.This article is a useful addition to the work of independent SAR wind retrieval. The experimental results herein show that it is feasible to employ the co-polarimetric backscattering coefficients and the polarimetric correlation backscattering coefficients for coastal wind field retrieval.
其他文献
A three-dimensional coordination polymer, [Ni(Hbyip ion is five-coordinated by three carboxylate O atoms from three different 5-(benzoic acid-4-yldiazenyl)isoph
We established an improved method for the determination of four estrogens including estriol (E3), 17β-estradiol (E2), 17α-ethynyl-estrodiol (EE2) and estrone
研究采用野外取样和室内萌发相结合的方法对湖南红壤丘陵区4种森林恢复类型下土壤种子库进行了比较研究。主要结论为:①草本植物是4种森林类型土壤种子库物种组成和个体数量的主要组成部分,其比例分别达61.9%-86.67%和49.82%-87.27%。4种植被类型种子库密度大小为:杉木林>湿地松林>油茶林>天然次生林;②天然次生林的灌木和乔木植物种子种类与数量多于人工林;③湿地松人工林和杉木人工林的人工抚
Role-Based Encryption (RBE) realizes access control mechanisms over encrypted data according to the widely adopted hierarchical RBAC model.In this paper,we pres
Cleaning of hollow-fibre polyvinyl chloride (PVC) membrane with different chemical reagents after ultrafiltration of algal-rich water was investigated. Among th
The wave motion over a submerged Jarlan-type breakwater consisting of a perforated front wall and a solid rear wall was investigated analytically and experiment
Homologous feature point extraction is a key problem in the optical and synthetic aperture radar(SAR) image registration for islands. A new feature point extraction method using a threshold shrink ope
Objective Calibrated Automated Thrombogram(CAT) is a test to monitor the generation of thrombin. It can be described by four parameters:lag time, peak thrombin,
句题和歌是日本文学所特有的一种体裁,其句题与和歌的关系是多样的,动态的.本文从句题和歌与中国文化东渐、句题和歌的性质--翻译、改写、创作和句题和歌的启示--诗学比较与
根据矿井放水试验、瞬变电磁法(TEM)探水资料及井下煤(岩)巷揭露断层时断层的淋水、涌水情况和断层两盘水文观测孔的水位变化情况,对断层导水性特征进行了分析.研究表明刘桥