Flooding Water Depth Estimation with High-Resolution SAR.pdf

IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING, VOL. 53, NO. 5, MAY 2015 2295 Flooding Water Depth Estimation With High-Resolution SAR Pasquale Iervolino, Student Member, IEEE, Raffaella Guida, Member, IEEE, Antonio Iodice, Senior Member, IEEE, and Daniele Riccio, Fellow, IEEE Abstract—The retrieval of flooding levels with high-resolution (HR) synthetic aperture radar (SAR) images is presented in this paper. A new framework is proposed. It is based on the inversion of theoretical scattering models initially developed for nonflooded ur- ban areas and here adapted to the flooding case. Starting from the theory, two possible retrieval approaches have been developed and are the main topic of this paper: two possible retrieval approaches have been developed and are the main topic of this paper: the local Single Image Objects Aware (SIObA) and the global Two Image Area Aware (TIArA). These two approaches are conceived to be applicable under different working conditions and consequently holding different properties and reliability. For each of them, a different algorithm is derived and tested, and the retrieval results are validated on a meaningful data set of HR TerraSAR-X images relevant to the Gloucestershire (U.K.) flooding that occurred in year 2007. Index Terms—Electromagnetic modeling, feature extraction, floods, inverse problems, Synthetic aperture radar (SAR). I. INTRODUCTION C LIMATE change is clearly playing an important role inthe current increase in flooding occurrence: That in the U.K. in 2007 and in 2014 or in Pakistan in 2010 are only some of the most devastating water disasters that happened recently. The loss in lives, properties, agricultural harvests, and infrastructures is anytime evaluated in terms of millions of dollars [1], [2], with peaks of billions per single event [1], thus justifying the research of efficient real-time technical solutions to synoptically monitor the increase of river/ocean levels and prevent or mitigate the event of floodin