The patterns of spring aufeis distribution, their relation with river runoff formation and hazardous phenomena in the Magadan region

In the last decade, the variability of aufeis formation processes in various natural and climatic conditions has been noted. Aufeis has a great impact on infrastructure and can lead to significant economic damage. Due to the active development of the Magadan region, there is a need for a regional assessment of the current state and formation of aufeis processes, including their impact on the hydrological regime of rivers and natural hazards. Methods. Based on the analysis of Landsat satellite images for the period 2013–2019, the number (2 510) and total area (1 132.3 km2) of spring aufeis in the Magadan region were estimated. The contribution of aufeis runoff to river streamflow in different periods of the hydrological regime was calculated based on the data of 23 hydrological gauges. Results. Based on the satellite images dated 2013–2019, we have developed an up-to-date catalog of the Magadan oblast groundwater aufeis. We have calculated, mapped and analyzed the regularities of the aufeis characteristics formation. The maps of aufeis state of Magadan oblast have been developed and the aufeis runoff contribution to the Kolyma River and the Okhotsk Sea basin rivers’ runoff to the hydrological regime various phases. The Nelkoba, Berelekh and Detrin rivers’ basins are characterized by the aufeis high values. These basins form the “golden belt” and are the Magadan oblast gold mining centers, so their further stdying is imperative.