Contemporary State of Glaciers in Chukotka and Kolyma Highlands ISSN 2080-7686
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Bulletin of Geography. Physical Geography Series, No. 19 (2020): 5–18 http://dx.doi.org/10.2478/bgeo-2020-0006 Contemporary state of glaciers in Chukotka and Kolyma highlands ISSN 2080-7686 Maria Ananicheva* 1,a, Yury Kononov 1,b, Egor Belozerov2 1 Russian Academy of Science, Institute of Geography, Moscow, Russia 2 Lomonosov State University, Faculty of Geography, Moscow, Russia * Correspondence: Russian Academy of Science, Institute of Geography, Moscow, Russia. E-mail: [email protected] a https://orcid.org/0000-0002-6377-1852, b https://orcid.org/0000-0002-3117-5554 Abstract. The purpose of this work is to assess the main parameters of the Chukotka and Kolyma glaciers (small forms of glaciation, SFG): their size and volume, and changes therein over time. The point as to whether these SFG can be considered glaciers or are in transition into, for example, rock glaciers is also presented. SFG areas were defined from the early 1980s (data from the catalogue of the glaciers compiled by R.V. Sedov) to 2005, and up to 2017: these data were retrieved from sat- Key words: ellite images. The maximum of the SGF reduction occurred in the Chantalsky Range, Iskaten Range, Chukotka Peninsula, and in the northern part of Chukotka Peninsula. The smallest retreat by this time relates to the gla- Kolyma Highlands, ciers of the southern part of the peninsula. Glacier volumes are determined by the formula of S.A. satellite image, Nikitin for corrie glaciers, based on in-situ volume measurements, and by our own method: the av- climate change, erage glacier thickness is calculated from isogypsum patterns, constructed using DEMs of individu- glacier reduction, al glaciers based on images taken from a drone during field work, and using ArcticDEM for others. stone glacier Introduction change are small glaciers or small forms of glaci- ation (Haeberli et al. 2004; Solomina et al. 2008), which are widely represented in the Kolyma and Mountain glaciers are one of the most sensitive nat- Chukotka highlands. The term “small forms of gla- ural indicators of climate change (Dyurgerov and ciation” (further SFG) was first introduced by M.V. Meier 2000; Hoelzle et al. 2007; Owen et al. 2009). Tronov in 1954 (Tronov 1954). It includes glaciers, The north-eastern part of Russia is almost com- perennial snow patches with an ice core and per- pletely occupied by mountains. Present glaciation is ennial snow patches. Small forms of glaciation are represented by a wide variety of glaciers. Despite in- also called “embryonic glaciation” (Shumsky 1955): tensification of glaciological research in north-east- (the term does not relate to young age). Those are ern Siberia in recent decades (Takahashi et al. 2011; spread in the South Island of Novaya Zemlya, the Ananicheva and Karpachevsky 2015; Kitov and Ply- Subpolar and Polar Urals, the Putorana Plateau, usnin 2015; Osipov and Osipova 2015; Stepanova et the mountains of Chukotka and Kolyma, and else- al. 2015; Shirakawa et al. 2016; Zhang et al. 2019), where. “Embryonic” glaciers do not often have a knowledge about the present state of glaciation in clearly pronounced firn basin, and are small in size this area remains incomplete. Even now, glacial for- and thickness; they have a morphological type – mations not previously described are found (Anan- corrie, corrie-hanging, corrie-valley – and are often icheva et al. 2019). Those most sensitive to climate © Author(s) 2020. This work is distributed under the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 License (http://creativecommons.org/ licenses/by-nc-nd/4.0/). Contemporary state of glaciers in Chukotka and Kolyma highlands A. Ananicheva et al. covered with moraine cover, which prevents them direction from the mouth of the Kolyma River to from melting during adverse climatic conditions. Dezhnev Cape. The Kolyma Highlands are adjacent The purpose of this work is to assess the main pa- to the western part of this region (Fig. 1). rameters of the Chukotka and Kolyma SFGs – their The Chukotka Highlands, where the glaciers size and volume, and changes therein over time. The are located, extend along the Chukchi Sea and are article discusses whether these small forms of glaci- represented by a system of medium-altitude rang- ation can be considered glaciers or are in a stage of es: Chantalsky (1,887 m a.s.l.), the long Pekulnei transition into, for example, rock glaciers. (1,400 m a.s.l.) and, to the south-east, the Iskaten Range (1,552 m a.s.l.). The basic relief of Chukotka is not alpine: instead, the mountains are flat-topped. Research area: topography and climate The highest massifs and ridges belong to glacial forms: cars, trough valleys, jagged ridges, and san- dur plains, subsequently modified by erosion. The Chukotka Peninsula (Chukchi Peninsula) occupies coastline is indented with deep bays and inlets. The the north-eastern extremity of the Eurasian conti- “middle-mountain” massifs of the Chukotka High- nent. Administratively, it is part of the Chukotka lands include mountain depressions of considera- Autonomous District (737.7 thousand km2). Chu- ble areal extent. kotka borders with Yakutia to the west, and Koryak A significant portion of the Chukotka Highlands Autonomous District to the south. The orograph- is part of the Okhotsk-Chukchi volcanogenic belt. It ic basis of Chukotka is a mountain-tundra plateau consists of almost continuous volcanic covers with (Sedov 2005). This watershed area stretches between intrusions breaking through them. The bedrock is the Arctic and Pacific oceans in a sub-latitudinal mostly composed of bazalts and andesites. The topography of the Taigonos Peninsula, a part of the Kolyma region, is represented by the Tyninot Fig. 1. Location of Chukotka and Kolyma glacier systems. Dotted circles with numbers highlight the distribution of glacier groups, indicated by R.V. Sedov 6 Citation: Bulletin of Geography. Physical Geography Series 2020, 19, http://dx.doi.org/10.2478/bgeo-2020-0006 A. Ananicheva et al. Contemporary state of glaciers in Chukotka and Kolyma highlands Range, which stretches 170 km from the south-west annual temperature is negative, according to Sedov to the north-east, from the Impoveem River to the (1997b): at weather stations Gizhiga (-5.4 °С), Tai- lower reaches of the Kechichma River. On average, gonos (-2.6 °C), precipitation is 284 and 484 mm, it rises up to 1,000 m a.s.l., and the highest point respectively. is 1,484 m a.s.l. (Sedov 1997a). The mid-mountain We estimated climate change by trends of climat- Tyninot Range (north of Chukotka Peninsula) is ic parameters important for the balance of glaciers characterised by steep scree slopes; glacial forms – temperature (mean annual Tyear and mean sum- such as sharp rugged ridges, through valleys, gla- mer Tsum) and precipitation (mean annual Pyear and cial lakes in valleys and at watersheds, and moraine for the cold period Psolid), see Table 1. For the last complexes. A major part of the Kolyma SFG is set 46 years (1966–2012). The year 1966 was chosen here. due to the improvement in precipitation measure- The western part of the Kolyma highlands is ment devices in the north of Russia in that year. The composed mainly of siltstones and sandstones, and Tyear and Tsum trends for the entire Chukotka Penin- the eastern part is of effusive deposits. Numer- sula are positive and vary from 1 to 2 °C for the ous granite intrusions appeared to be sources of 46 years – from the coast to the peninsula interior. non-ferrous metal ore. The precipitation trends of Pyear and Psolid are similar: The Arctic and Pacific oceans are basic factors they are both negative in the coastal regions and forming the region’s climate. Therefore, the climatic positive in the continental part between the Cross conditions of the Chukotka Highlands are quite di- and Anadyr gulfs. But in absolute terms, they dif- verse – from subarctic marine (in the northern part fer somewhat: Pyear from -100 (most of the Chukot- of Chukotka Peninsula) to the subarctic continen- ka Peninsula) to +100 mm for the 46 years (on the tal (in the Chantalsky Range, see Fig. 1), and Arctic plateau near the Gulf of Anadyr), Psolid from -110 to ones (in the far north). Strong winds play an im- +100 mm for the 46 years. However, a larger part of portant role in the winter season; they form a pow- Chukotka is characterised by a trend of -50 mm for erful snow transfer (storms), providing the small the 46 years (Fig. 2). glaciers with their nourishment. The Providensky Climatic processes over Chukotka do not pro- Mountain Massif (Fig. 1, 2) is located in the subarc- mote the development and spread of glaciation. The tic maritime climate, but with a large temperature assessment of the studied glaciers’ state dates to the amplitude: the mean temperature is 7.2 °C in sum- 1980s, since which time climate warming has been mer (June–August), and 14.3 °C in winter (Decem- characteristic for this region. We estimated the tim- ber–February). The smallest amount of precipitation ing of temperature and precipitation changes in the falls in June and averages 28 mm, and the greatest region (and the stations used are listed in Table 1). is 90 mm in November. On average, about 700 mm The increase in Tyear, Tsum occurs first for the in- of precipitation falls annually in Providence Bay, in ner region to the west of the Chukotka Peninsu- the southern part of Chukotka Peninsula, which is la – from the late 1970s to the early 1980s, and a feature of the maritime climate. later (from the early 1990s) the positive tempera- The climate of the Kolyma region, in particu- ture trend began in the region of 66–68° N, in the lar the mountain ranges of the Taigonos Peninsula north of the Chukotka.