Morphological evolution of the Arctic Tiksi coastline and driving mechanisms

Abstract

The Arctic's rapid recent warming has made it a major focus of climate change research and opened new Arctic shipping routes. Coastal areas, especially coastlines, reflect these changes, making their study essential for understanding climate impacts and ecosystem shifts. Nevertheless, despite growing interest in Arctic coastlines, big gaps remain in our grasp of shoreline dynamics—particularly regarding fractal dimension (FD) analysis and in how temperature and sea-ice changes shape them. Using Landsat imagery and GIS, this study charts how coastline length and FD changed around Tiksi, Sakha Republic, Russia, from 1973 to 2023. The research employs time-series analyses, including the Mann-Kendall trend test, Pearson correlation, and Granger causality testing, to explore the relationship between environmental variables such as surface temperature, sea level, and sea ice conditions. The results indicate a consistent increase in coastline length (the total linear extent of the land-sea interface in the study area, rising from 15.62 km to 18.72 km) and in FD (a dimensionless index quantifying shoreline geometric complexity, increasing from 1.01618 to 1.05854) over the 50-year period, with significant human influence observed, especially in the early years. Furthermore, changes in sea surface temperature have shown strong correlations with changes in coastline dynamics. The study underscores the critical role of environmental variables in shaping Arctic coastlines and highlights the unique contribution of FD analysis in understanding the complexities of coastal changes in the Arctic. This research offers valuable insights into Arctic coastal dynamics and contributes to future climate modeling and mitigation strategies.