Baseline data for monitoring geomorphological effects of glacier lake outburst flood: A very high-resolution image and GIS datasets of the distal part of the Zackenberg River, northeast Greenland

Abstract. The Arctic regions experience intense transformations, such that efficient methods are needed to monitor and understand Arcticlandscape changes in response to climate warming and low-frequency high-magnitude events. One example of such events,capable of causing serious landscape changes, is glacier lake outburst floods. On 6 August 2017, a flood event related to glacial lake outburst affected the Zackenberg River (NE Greenland). Here, we provided a very high-resolution dataset representingunique time-series of data captured immediately before (5 August 2017), during (6 August 2017), and after (8 August 2017)the flood. Our dataset covers a 2.1-km-long distal section of the Zackenberg River. The available files comprise: (1)unprocessed images captured using an unmanned aerial vehicle (UAV): https://doi.org/10.5281/zenodo.4495282 (Tomczykand Ewertowski, 2021a); and (2) results of structure-from-motion (SfM) processing (orthomosaics, digital elevation models, and hillshade models in a raster format), uncertainty assessments (precision maps) and effects of geomorphological mappingin vector formats: https://doi.org/10.5281/zenodo.4498296 (Tomczyk and Ewertowski, 2021b). Potential applications of thepresented dataset include: (1) assessment and quantification of landscape changes as an immediate result of glacier lakeoutburst flood; (2) long-term monitoring of high-Arctic river valley development (in conjunction with other datasets); (3)establishing a baseline for quantification of geomorphological impacts of future glacier lake outburst floods; (4) assessment of geohazards related to bank erosion and debris flow development (hazards for research station infrastructure – station buildingsand bridge); (5) monitoring of permafrost degradation; and (6) modelling flood impacts on river ecosystem, transport capacity,and channel stability.