Evolving Outlines Of Antarctic Active Subglacial Lakes Using An Image Processing Algorithm On Gridded Altimetry Data

This investigation quantifies the dynamic geometries of Antarctic active subglacial lakes by leveraging satellite altimetry data and an image processing algorithm. Using high-resolution altimetry satellite data from 2010 to 2023 and a computer-vision-based contour finding algorithm to delineate contours of ice-surface, height-change anomalies indicative of lake activity, we generated evolving outlines of 131 previously identified Antarctic active subglacial lakes. Evolving outlines provided a novel time series of wetted area to quantify changes in the bed substrate available for geochemical and microbial processes. Evolving outlines revealed previously unseen transitory lake lobes that refine preexisting time series of height change and ice-volume displacement, from which we can infer subglacial water flux. The findings underscore the value of employing evolving subglacial lake outlines to record active subglacial lake geometric changes across Antarctica and suggest broader glaciological applications, such as the identification of new active subglacial lake candidates.