Real-time estimation of lake volume and river discharge from satellite altimetry and remotely sensed imagery in ungauged basins

遥感提供了一种机制，通过监测水库和湖泊水位以及河流流量，对缺水和洪水造成的风险和潜在生命损失进行预警。此外，许多河流集水区是通过为水力发电、渔业和水资源建造水坝来管理的，这些水坝往往对生计，特别是下游的生计产生不利影响，而主要集水区的河流流量要么缺乏测量数据，要么无法获得数据。由于世界上许多地方缺乏降水数据，有关缺水或洪水事件的信息往往无法传达到下游，从而可能造成灾难性后果。可以通过卫星测高恢复湖泊或水库水位和容量以及河流水位高度和流量的近实时量化，根据近实时卫星图像估计湖泊面积或河流宽度，以及建立水位-流量关系的某种机制，可能是基于单一测量数据或水文模型。该项目将为最新的延迟多普勒型高度计（Cryosat-2和Sentinel 3号卫星上）开发近实时能力，同时沿着河流和水库范围的光学和合成孔径雷达图像。河流掩膜将用于将卫星测高限制在内陆水域目标上，但也提供河流宽度和湖泊范围，以推断流量和湖泊体积的变化。这种能力将降低与停水和洪水相关的风险，提供时间间隔小于24小时的早期预警，这受到用户可获得快速查看卫星高度波形的时间的限制。

Remote sensing provides the mechanism for forewarning the risks and potential loss of life due to water failure and flooding through the monitoring of reservoir and lake levels, and river discharge. Further, many river catchments are managed with dams constructed for hydroelectric power, fisheries and water resource, and these dams often have a detrimental effect on livelihoods, particularly downstream, while river discharge across major catchments suffer from either lack of gauge data or data unavailability. With precipitation data lacking in many parts of the world, information concerning water failure or flood events is often not communicated downstream with potentially catastrophic consequences.Near real-time quantification of lake or reservoir levels and volumes, and river stage heights and discharge can be recovered from satellite altimetry, an estimation of the lake area or river width from near real-time satellite imagery and some mechanism to develop a stage-discharge relationship, perhaps based on a single gauge data or hydrological modelling. This project will develop a near real-time capability for the latest delay-doppler type of altimeter (onboard the Cryosat-2 and Sentinel3 satellites) along with optical and Synthetic Aperture Radar imagery for river and reservoir extent. The river mask will be used to both constrain the satellite altimetry to the inland water target, but also supply river width and lake extent for inferences of variations in discharge and lake volumes.Such a capability will reduce the risk associated with water failure and floods, providing an early warning with time lapse of less than 24 hours, limited by the time that the quick look satellite altimetric waveforms are made available to the user.