NDWI as a method for studying natural and technogenic aufeis along the Lena Highway (Southern Yakutia)

The research conducted has yielded, for the first time, a quantitative evaluation of the NDWI (Normalized Difference Water Index) for the purpose of identifying areas of natural and technogenic aufeis within Southern Yakutia. In contrast to the widely used NDSI (Normalized Difference Snow Index) in aufeis investigations, the NDWI offers the advantage of delineating aufeis contours without being influenced by the presence or absence of snow cover. Calculations pertaining to the aufeis areas in the “Gorbyllakh” and “Durai” sections of the Federal Highway “Lena” during the winters of 2020–2021 and 2021–2022 indicate a notable increase in these areas, attributed to heightened precipitation levels anticipated in the subsequent summer period. However, limitations of this approach include the interference of cloud cover in satellite imagery, which can obscure the study area, as well as the potential for ambiguous interpretations of shaded regions within the aufeis meadow, where the NDWI may suggest the presence of surface water.