上升流是一种普遍存在于海洋中的海水垂直向上涌升现象，对海洋与大气相互作用、海洋营养物质再分配有重要影响，也是我国著名舟山渔场形成的主要因素。星载合成孔径雷达（Synthetic Aperture Radar, SAR）由于其特有的观测能力，是目前研究上升流的重要技术手段。舟山海域上升流除了具有显著低温区外，含有高浓度泥沙是其独有的特点，但是二者对上升流SAR成像机制的影响研究尚不透彻。据此，本项目利用SAR卫星数据，结合其他卫星数据和现场海洋水文环境数据，在现有SAR海面成像仿真模型基础上，研究海表温度和泥沙含量对舟山上升流SAR成像的影响，建立更精确的舟山上升流SAR散射模型。同时，针对SAR上升流图像主要表现为弱散射的特点，研究弱散射区散射信息以及海表水平流速信息高精度提取方法。本项目的研究结果能够完善舟山上升流SAR成像机制，为更深刻的理解舟山上升流形成物理海洋机制提供重要依据。

Upwelling is a common oceanic phenomenon defined as sea water upwelling vertically to sea surface. It has significant impact on air-sea carbon cycle and marine nutrients redistribution. It is also a major factor of forming famous Zhoushan fishery in China. Space-borne synthetic aperture radar (SAR) is an important instrument to observe upwelling for its distinctive advantage. High suspended sediment concentration is a unique characteristic of Zhoushan upwelling area where obvious low sea surface temperature (SST) region can often be found. In order to study the effect of SST and suspended sediment concentration on upwelling SAR imaging, first SAR data combined with other satellite and in-situ oceanic environmental data will be collected. Second, how to establish a more accurate SAR scattering model for Zhoushan upwelling area will be studied based on the existing SAR imaging simulation models. In the end, the method to extract high accurate scattering information and sea surface velocity of upwelling area in SAR images which shows a feature of low scattering will be also studied. The work of this proposal will improve existing mechanisms of SAR imaging, provide important evidences to understanding of physical formation of Zhoushan upwelling.