RIVER SYSTEMS CLASSIFICATION - TOWARDS INLAND WATER HEIGHT RETRIEVAL FROM SENTINEL3

摘要

The advent of SAR altimeters presents bothrnopportunities and challenges for retrieval of riverrnsurface heights. While lake levels have been wellrnmonitored by prior altimeter missions, these missionsrnhad varying success at capturing the more challengingrnriver targets. This paper examines the global capabilityrnof prior altimeters over rivers and presents statisticsrnshowing that Envisat was the most successful altimeterrnto date for river monitoring. The requirement for onern‘clean’ echo is found to be the fundamental constraintrnon river height retrieval.rnA detailed Cryosat2 data analysis is performed overrnthree river systems to provide a forward look towardsrnSentinel3 performance over inland water. Both SAR andrnLRM echoes are analysed. More than 70% of echoes arernfound to be complex multi-target responses, a far higherrnproportion than in previous missions; however, ‘clean’rnwater echoes are found throughout all three riverrnsystems and in both SAR and LRM modes.