Severnaya Zemlya – an archipelago which separates the Kara Sea and the Laptev Sea, to the north of the Taymyr Peninsula, across the Vilkitsky Strait (60–90 km wide). It is the northernmost part of Asia. It is the western border of the Laptev Sea. Administratively it refers to Taymyr (Dolgano-Nenets) Autonomous Area, Russia. It was the last vast land discovered on our planet. The archipelago consists of four major islands – the October Revolution Island, the Bolshevik Island, the Komsomolets Island, the Pioneer Island, and lots of minor islands of total area around 37,000 km2.
In the south S. Z. (the Bolshevik Island) is separated from the mainland coast (the Taymyr Peninsula) by the Vilkitsky Strait (60–90 km). The S. Z. Islands Bolshevik and October Revolution are separated by the Shokalsky Strait (20–50 km); Krasnoyarmyy Strait separates the October Revolution Island from the Komsomolets and the Pioneer Islands, with the latter being separated by the Yuzhny Strait. Near the eastern coast of S. Z., to the east from the Bolshevik Island, two large islands are located – the Maly Taymyr Island and the Starokadomsky Island.
S. Z. is a strongly denuded and lowered folded older mass, like the Taymyr Peninsula. The Proterozoic and Paleozoic layers contain large folded strata of sand rock, shale rock, chalkstone, lava, structural accumulations, gabbro–diabase dikes, and granite intrusions. Afterward the Taymyr folded structure was elevated two times. S. Z’s present landscape developed due to rock displacement in the following geologic ages. The most part of S. Z. is represented by high plateau, formed by metamorphic rocks of old folded structures. A dense network of hollows with smooth slopes is widely represented. Plateau tops are covered with ice and are cup shaped, often with block deposits and stone polygons, stretched into straps along the slope, agglomerations of glacial clay boulders. Plateaus are separated by deep canyons with waterfalls at the bottom. Rocks of the eastern coast of the October Revolution Island and the western coast of the Bolshevik Island form vertical cliffs plunging into the sea. They are 400–500 m above the sea level and covered with troughs filled with ice. Some troughs flooded with seawater form fjords, e.g., Matusevich Fjord wedging into the land for almost 80 km. Fragile carbonate and shale rocks formed flat land and are stepped due to stops during retreat of glaciers. Solifluction is developing over smooth slopes adjacent to glaciers and snow patches. Fine earth mounds, sometimes encircled by stone circles, and polygon structures with vegetation in tiny spots of low ground occur. Low coastal plains are to be mainly found on the western shore of the islands. For smaller islands low coastal plains are the only type of landscape. The coasts here are edged with lagoons, small bays, and tongues of sand and pebble. Shallows are widespread, so the shoreline changes considerably during tides. The surface of coastal plains is typical, small-scale polygonal, covered with the network of rivers and streams, and speckled with lake-like lagoons. Strong inland ice, the most characteristic feature of S. Z. nature, 18,300 km2 in area (47.6 % of surface), hides almost a half of the archipelago surface. Principal forms of ice cover are separate glacial sheets and caps. Akademiya Nauk ice cap, covering 70 % of the Komsomolets Island surface, is an ice sheet. The Schmidt Island is fully covered with ice cap. The Karpinsky ice cap on the October Revolution Island is where the highest point of S. Z. – 965 m – is located. Multiple nunataks tower over ice caps. Shifting ice tongues jut out of ice covers, the largest of them reaching the sea. Ice boulders 200 × 500 m in size come off them. S. Z. is where the lowest snow line in Asia is to be found (50–100 m, on the Bolshevik Island – 300–400 m). Land surface here was strongly influenced by ice. Traces of glacier retreat are to be found everywhere in the form of old boulder trains, hanging valleys, and stones, but distinct glacial relief forms are created only where the ice stream is constrained and the bed slope is steep. There is no dead ice at all.
Hydrographic network of S. Z. is well developed, in spite of the fact that the rivers are small in size. Comparatively dense river network exists on the October Revolution Island, the Bolshevik Island, and the Komsomolets Island, where large land plots are free from ice.
The largest water flows are the Ushakov River (58 km long) and the Ozernaya River (55 km long) on the October Revolution Island, the Tora River (54 km) and the Lagernaya River (49 km) on the Bolshevik Island, the Mnogostruynaya River (36 km) on the Komsomolets Island, and the Kruglaya River (32 km) on the Pioneer Island. Water content of rivers is very diverse. Melting and release of melt water into rivers occur only in relatively short warm season. The rivers are mostly of glacier-derived nourishment.
A significant part of the S. Z. hydrographic network belongs to lakes, with the largest ones on the October Revolution, Komsomolets, and Bolshevik Islands. Total area of lakes equals to 233 km2.
The climate of the archipelago is one of the harshest in the world. Average air temperatures (−13…–16 °C) are aggravated by strong winds in January – from 18 to 34 m/s. Due to the crystallitic dusty snow structure, the storm starts if the wind is 4–5 m/s, and if it reaches 8 m/s, snowstorm starts. Snow cover settles in the end of September and goes by the beginning of June. Average monthly temperatures are −28…−33 °C in winter and +0.5…1.6 °C in summer. In July, subzero temperature holds up to 18 days in average. Annual precipitation amounts to 150–300 mm, with most of it falling in August. In some years the seas washing S. Z. are covered with pack ice and ice mounds even in summer. When ice mounds and icebergs hit the ground, they form high (up to 20 m) picturesque ice hummocks. The Vilkitsky Strait is free from ice in summer only in the warmest years. The Shokalsky Strait is more accessible for navigation: near its eastern coast, open water can be seen even in winter. A cloudy weather is a characteristic of S. Z., especially in October and March. It is often foggy in summer. From April to June, transparent Arctic air dominates for longer periods. In the midday stones can warm up to 10–12 °C, forming thaw holes around them. In the night their temperature falls down to –40 °C. The soil of the islands is mostly desert arctic and typically arctic. Areas of the archipelago free from snow are arctic deserts, scant even in comparison with other arctic islands. The Bolshevik Island is the only one where moss and lichen cover 20–30 % of the surface; on the other islands, they are tiny spots on the stony land. Coastal plains covered with gramineous and moss tundra and dense hemispheric bunches of hair grass and snow grass are richer in vegetation. On drained plots moss is substituted by lichen (Cetraria). Moss is covered by crawling polar willow, scattered flowers of arctic poppy, saxifrage, forget-me-not, and ranunculus – near snow spots.
Typical faunal forms of S. Z. are lemmings and arctic foxes; on the Bolshevik Island, reindeer can sometimes be met. The Bolshevik Island is one of the main “maternity homes” of polar bears. By number of bird species (20), S. Z. holds the last place among polar islands. Bird colonies are abundant only in the Matusevich Fjord and on the rocks of the eastern coast, weathered by frost. Colonies having thousands of seagulls, guillemots, and kittiwakes are located there. S. Z. is the eastern border of little auk areal, the smallest and the most agile northern bird. The substrate of bird colonies is the soil for saxifrage and starwort. The seas washing the archipelago are home to bearded seals and Greenland seals. Shore floe is the usual habitat of ringed seal. Walruses can be met there. Polar navaga and cod are followed by beluga (polar dolphin); schools counting thousands of them were seen near the eastern coasts.
The Sredny Island is where the famous Arctic airport is located, with air routes to the Franz Josef Archipelago and to drifting stations “North Polar.” Groups of researchers and ships arrive here. Industrially, S. Z. is as attractive as the Taymyr Peninsula: on the archipelago of copper, tin, wolfram, ferrum, coal, and oil. But first of all, it needs establishing natural reserve, which would include unique inland ice and coasts with ice holes and water leads, where birds, walruses, and polar bears are feeding. In terms of geological time, S. Z. ecosystems might be the youngest existing, which have been covered with ice until recently.
S. Z. was discovered in the beginning of the twentieth century, though islands to the north of Taymyr had been mentioned since the sixteenth to seventeenth centuries. The guesses on the existence of the unknown land were based on the observations of local people, who watched migration of geese, Arctic foxes, and polar bears. However, neither S. Chelyuskin nor, much later, N. Nordenskiöld, F. Nansen, and E. Toll could find S. Z. It was the expedition of B. Vilkitsky, which was traveling the Northern Sea Route in 1913, that hit rocky coasts of an unknown land. The discovered eastern coast was named Emperor Nicholas II Land and the Russian flag was raised there. First physiographic data on S. Z. was received by the expedition of G. Ushakov and N. Urvantsev in 1930–1932.