Review article: Feature tracing in radio-echo sounding products of terrestrial ice sheets and planetary bodies

<p>This paper aims to inform researchers and practitioners in radioglaciology about current and future trends in mapping the englacial stratigraphy of ice sheets. Radio-echo sounding (RES) is a useful technique for measuring the subsurface properties of ice sheets and glaciers. One of the most important and unique outcomes is the mapping of ice sheets' englacial layer stratigraphy, mainly consisting of isochronous reflection horizons. Mapping those is still a labor-intensive task. This review provides an overview of state-of-the-art (semi-)automated methods for identifying ice surface, basal, and internal reflection horizons from radargrams in radioglaciology. Methods for segmenting (and detecting) different regions of radargrams are also included due to their data and methodological similarity to methods tracing internal reflection horizons. We discuss a variety of methods which have been developed or applied to RES data over the last few decades, including image processing, statistical techniques, and deep learning approaches. For each approach, we briefly summarize their procedures, challenges, and potential applications. Despite major advances, we conclude that gaps remain in effectively mapping internal reflection horizons in an automated way but with deep learning representing a potential advancement.</p>