GIANT AUFEIS-TARYN IN THE NORTHEAST OF RUSSIA ACСORDING TO THE CADASTER (1958) AND SATTELITE IMAGES OF 1973-2021
O.M. Makarieva1,2, A.N. Shikhov1,3, A.A. Zemlianskova1,2, V.R. Alexeev4, N.V. Nesterova1,5, A.A. Ostashov1,5
1St. Petersburg State University, Institute of Earth Sciences, St. Petersburg, Russia
2North-Eastern State University, Magadan, Russia
3Perm State University, Perm, Russia
4Melnikov Permafrost Institute, Siberian Branch of the Russian Academy of Sciences, Yakutsk, Russia
5State Hydrological Institute, St. Petersburg, Russia
Keywords: giant aufeis-taryn, Landsat images, Cadaster (1958), aufeis glade, North-East of Russia
Abstract
Data on the actual maximum area of 71 largest aufeis-taryn in the North-East of Russia (with an area of at least 10 km2) based on the results of interpretation of Landsat satellite images in 2013-2018 (661 km2) and Sentinel-2 in 2020-2021 (838 km2) is presented. The total area of aufeis fields turned out to be at least 2 times lower than the total area of aufeis glades indicated in the Cadaster of aufeis of the North-East (1958) (1680 km2). For 42 objects the area for 1973-1975 were also obtained according to Landsat/MSS data (before the beginning of the warming period). The total value was 555 km2, which is close to modern estimates for 2020-2021 (581 km2), and on average. 1.9 times lower than their total area according to the Cadastre (1958) (1083 km2). Despite the fact that individual giant aufeis show very high interannual variability, their area can change up to two times from year to year (100 %), on average for most aufeis fields this value is about 20 %. On numerous examples, a discrepancy between the contours of aufeis glades and the boundaries of aufeis fields was established. The total area of aufeis glades, both indicated in the Cadaster (1958) and identified on the basis of modern space images, significantly exceeds the actual area of aufeis. Estimating the area of aufeis (even the maximum in a long-term period) by the size of aufeis glades can lead to significant errors in the calculation of the dynamic reserves of aufeis groundwater and other characteristics. In the period after 1973-1975 significant change of total aufeis area in the North-East were not identified. Further field studies of giant aufeis are important to identify the causes of their variability, including the establishment of long-term regime observations at special aufeis research plots.
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