The Full Potential of EO for Flood Applications: Managing Expectations

Abstract The ability to map floods from satellites has been known for over 40 years. Early images of floods were rather difficult to obtain and flood mapping from satellites was thus rather opportunistic and limited to only a few case studies. However, over the last decade, with a proliferation of open-access Earth Observation (EO) data, interoperability, and the Internet of Things, there has been much progress in the development of EO products and services tailored to various end-user needs. EO has clearly entered a new era now, where, with respect to flood mapping, various services are offered but many challenges still remain, particularly in relation to satellite signal interactions within vegetated and urban environments. Also, major limitations in measuring critical flood variables directly from remote sensing, such as flow depth and velocity, and the lack of open-access high-accuracy auxiliary global datasets, such as topography, seriously hamper the development of reliable flood mapping algorithms that work well anytime and anywhere and can be deployed locally as well as globally across cloud compute services. All these non-trivial challenges present pitfalls but also opportunities and in order to unlock the full potential of EO for flood applications, scientists, product developers, and end-users alike need to manage expectations and form partnerships.