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41-535: The area has rugged mountain terrain with altitudes of up to 633 metres (2,077 ft). Much of the relief of the peninsula is a paleic surface similar to the one found in the highlands of southern Norway. In the peninsula the paleic surface is made up of an undulating plateau between the altitudes of 200 and 600 m.a.s.l. The higher parts of the undulating plateau are made up by erosion-resistant rocks like quartzite . The lower parts are made up by weak rocks like shale and mudstone . At intermediate levels sandstone

82-553: A temperate grassland , restricting southern tundra to coastal Antarctica and its islands. The flora and fauna of Antarctica and the Antarctic Islands (south of 60° south latitude) are protected by the Antarctic Treaty . Alpine tundra does not contain trees because the climate and soils at high altitude block tree growth. The cold climate of the alpine tundra is caused by the low air temperatures, and

123-757: A local climate in which at least one month has an average temperature high enough to melt snow (0 °C (32 °F)), but no month with an average temperature in excess of 10 °C (50 °F). The cold limit generally meets the EF climates of permanent ice and snows ; the warm-summer limit generally corresponds with the poleward or altitudinal limit of trees, where they grade into the subarctic climates designated Dfd , Dwd and Dsd (extreme winters as in parts of Siberia ), Dfc typical in Alaska, Canada, mountain areas of Scandinavia , European Russia , and Western Siberia (cold winters with months of freezing). Despite

164-472: A paleic surface extends in Varanger Peninsula . In the peninsula the paleic surface is made up of an undulating plateau between the altitudes of 200 and 600 m.a.s.l. The higher parts of the undulating plateau are made up by erosion-resistant rocks like quartzite . The lower parts are made up by weak rocks like shale and mudstone . At intermediate levels sandstone is common. Some parts of

205-485: Is a risk of wildfire, such as the 1,039 km (401 sq mi) of tundra which burned in 2007 on the north slope of the Brooks Range in Alaska. Such events may both result from and contribute to global warming. Carbon emissions from permafrost thaw contribute to the same warming which facilitates the thaw, making it a positive climate change feedback . The warming also intensifies Arctic water cycle , and

246-664: Is an erosion surface of gentle slopes that exist in South Norway . Parts of it are a continuation of the Sub-Cambrian peneplain and Muddus Plains found further east or equivalent to the strandflat coastal plains of Norway. Hardangervidda , a particularly flat and elevated part of the Paleic surface formed in the Miocene at sea level. Although the tilted plateau-like topography of south Norway had been noted since

287-453: Is characterized by plants that grow close to the ground, including perennial grasses , sedges , forbs , cushion plants , mosses , and lichens . The flora is adapted to the harsh conditions of the alpine environment, which include low temperatures, dryness, ultraviolet radiation, and a short growing season. Tundra climates ordinarily fit the Köppen climate classification ET , signifying

328-533: Is common. Some parts of the paleic surface in Varanger Peninsula are a re-exposed unconformity that underlie sedimentary rock of Vendian ( Late Neoproterozoic ) age. The paleic surface might have been uplifted as much as 200–250 meters since middle Pliocene times. Landforms resulting from Quaternary periglaciation are recurrent across the peninsula. Among the most common are block fields and solifluction lobes . Blockfields are most extensive on

369-784: Is home to several peoples who are mostly nomadic reindeer herders, such as the Nganasan and Nenets in the permafrost area (and the Sami in Sápmi ). Arctic tundra contains areas of stark landscape and is frozen for much of the year. The soil there is frozen from 25 to 90 cm (10 to 35 in) down, making it impossible for trees to grow there. Instead, bare and sometimes rocky land can only support certain kinds of Arctic vegetation , low-growing plants such as moss, heath ( Ericaceae varieties such as crowberry and black bearberry ), and lichen . There are two main seasons, winter and summer, in

410-630: Is light, evaporation is also relatively minimal. During the summer, the permafrost thaws just enough to let plants grow and reproduce, but because the ground below this is frozen, the water cannot sink any lower, so the water forms the lakes and marshes found during the summer months. There is a natural pattern of accumulation of fuel and wildfire which varies depending on the nature of vegetation and terrain. Research in Alaska has shown fire-event return intervals (FRIs) that typically vary from 150 to 200 years, with dryer lowland areas burning more frequently than wetter highland areas. The biodiversity of tundra

451-698: Is low: 1,700 species of vascular plants and only 48 species of land mammals can be found, although millions of birds migrate there each year for the marshes. There are also a few fish species. There are few species with large populations. Notable plants in the Arctic tundra include blueberry ( Vaccinium uliginosum ), crowberry ( Empetrum nigrum ), reindeer lichen ( Cladonia rangiferina ), lingonberry ( Vaccinium vitis-idaea ), and Labrador tea ( Rhododendron groenlandicum ). Notable animals include reindeer (caribou), musk ox , Arctic hare , Arctic fox , snowy owl , ptarmigan , northern red-backed voles , lemmings ,

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492-404: Is similar to polar climate . Alpine tundra is generally better drained than arctic soils. Alpine tundra transitions to subalpine forests below the tree line; stunted forests occurring at the forest-tundra ecotone (the treeline ) are known as Krummholz . Alpine tundra can be affected by woody plant encroachment . Alpine tundra occurs in mountains worldwide. The flora of the alpine tundra

533-600: The Arctic fox , which is critically endangered on the Norwegian mainland. In addition to introducing animals into nature, the larger and stronger red fox is hunted down. There are many species of sea birds along the coast of the peninsula; some arctic species of birds spend the winters along the coast of the peninsula. Paleic surface The paleic surface or palaeic surface ( Norwegian : paleiske overflaten , from Ancient Greek palaios  'old' )

574-859: The Baltic Shield . Two ancient fault systems divide the geology of the peninsula into three groups, where the NE side of the peninsula (North Varanger region) is separated from the SW by the Trollfjord-Komagelva strike-slip fault , and the SW side is divided approximately NNE-SSW by thrusting of the Scandinavian Caledonides over the Baltic Shield. In the North Varanger region, sedimentary rocks were deposited during

615-586: The Kerguelen Islands . Most of Antarctica is too cold and dry to support vegetation, and most of the continent is covered by ice fields or cold deserts. However, some portions of the continent, particularly the Antarctic Peninsula , have areas of rocky soil that support plant life. The flora presently consists of around 300–400 species of lichens, 100 mosses, 25 liverworts , and around 700 terrestrial and aquatic algae species, which live on

656-644: The Marinoan ' Snowball Earth ' (Smalfjord Formation of the Vestertana Group), and the overlying ' cap carbonate ' of the Nyborg Formation (Vestertana Group). Small outcrops of barite crystals related to 'Snowball Earth' deglaciation are found locally on outcrops of the Baltic Shield. A part of the peninsula, including the town of Vardø (located on an island just off the coast of the peninsula), earlier had an Arctic tundra climate but with

697-1013: The Tonian /early-mid Cryogenian (Barents Sea Group), followed by a depositional hiatus that lasted until the late Ediacaran , when the Løkvifjell Group was deposited. Notable strata of the Barents Sea Group are the Kongsfjord and Båsnæring formations, which form prominent ridges and cliffs along the Fv341 road. Outcrops of the overlying Båtsfjord Formation are generally not as prominent, but are notable for containing molar tooth structures , as well as teepee structures , desiccation cracks , flaser bedding , and other sedimentary structures that indicate deposition in an inter-tidal, intermittently exposed environment. Stable carbon isotope ratio chemostratigraphy has been used to correlate

738-472: The mosquito , and even polar bears near the ocean. Tundra is largely devoid of poikilotherms such as frogs or lizards. Due to the harsh climate of Arctic tundra, regions of this kind have seen little human activity, even though they are sometimes rich in natural resources such as petroleum , natural gas , and uranium . In recent times this has begun to change in Alaska , Russia, and some other parts of

779-530: The strandflat . Tundra In physical geography , tundra ( / ˈ t ʌ n d r ə , ˈ t ʊ n -/ ) is a type of biome where tree growth is hindered by frigid temperatures and short growing seasons. There are three regions and associated types of tundra: Arctic tundra, alpine tundra , and Antarctic tundra. Tundra vegetation is composed of dwarf shrubs , sedges , grasses , mosses , and lichens . Scattered trees grow in some tundra regions. The ecotone (or ecological boundary region) between

820-641: The Annijokka Member of the Båtsfjord Formation with other Neoproterozoic successions around the world, suggesting it was deposited approximately 811 million years ago, during the Bitter Springs carbon isotope excursion. Strata deposited on the SW half of the Varanger Peninsula mostly formed during the mid-late Cryogenian , Ediacaran , and Paleozoic . Notably, this includes glacial diamictite sedimentary rocks that formed during

861-503: The Paleic surface are thought to have been formed by etching and stripping and pediplanation . The climate under which these processes occurred was likely warmer than the present. Much of the paleic surface in southern Norway was at sea level or below during the Miocene . In the Early Pliocene (5–4 million years ago) the surfaces such as Hardangervidda were uplifted by tectonic forces 1.2 km. The peneplain surfaces of

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902-602: The areas of exposed rock and soil around the shore of the continent. Antarctica's two flowering plant species, the Antarctic hair grass ( Deschampsia antarctica ) and Antarctic pearlwort ( Colobanthus quitensis ), are found on the northern and western parts of the Antarctic Peninsula. In contrast with the Arctic tundra, the Antarctic tundra lacks a large mammal fauna, mostly due to its physical isolation from

943-565: The atmosphere, creating a feedback cycle that changes climate. The term is a Russian word adapted from the Sámi languages . Arctic tundra occurs in the far Northern Hemisphere , north of the taiga belt. The word "tundra" usually refers only to the areas where the subsoil is permafrost , or permanently frozen soil. (It may also refer to the treeless plain in general so that northern Sápmi would be included.) Permafrost tundra includes vast areas of northern Russia and Canada. The polar tundra

984-493: The climate system activated around 2 °C (3.6 °F) of global warming suggested that at this threshold, permafrost thaw would add a further 0.09 °C (0.16 °F) to global temperatures by 2100, with a range of 0.04–0.16 °C (0.07–0.29 °F) Antarctic tundra occurs on Antarctica and on several Antarctic and subantarctic islands, including South Georgia and the South Sandwich Islands and

1025-564: The early 1800s, the first formal description was by Hans Reusch in 1901, using a denudation chronology approach invoking several of W.M. Davis ’ ideas of a cycle of erosion . Reusch also coined the name Paleic surface . The Paleic surface is sometimes erroneously considered equal to Norway's "pre-glacial surface" – the surface that existed in Norway just before the Quaternary glaciations . There have been various attempts at defining

1066-533: The highest of the stepped surfaces. These mountains define a former envelope surface that is warped. Possibly the warping of the envelope surface reflects doming of the crust associated with the uplift of the Scandinavian Mountains in the Cenozoic. The Paleic surface has been reconstructed over the fjord area of western Norway. In the reconstructed paleic surface, very gentle valleys follow

1107-488: The increased amounts of warmer rain are another factor which increases permafrost thaw depths. The IPCC Sixth Assessment Report estimates that carbon dioxide and methane released from permafrost could amount to the equivalent of 14–175 billion tonnes of carbon dioxide per 1 °C (1.8 °F) of warming. For comparison, by 2019, annual anthropogenic emission of carbon dioxide alone stood around 40 billion tonnes. A 2018 perspectives article discussing tipping points in

1148-532: The northern half of the peninsula, chiefly in the plateau area. Polygonal ground is found in some places, but there are no known modern ice wedges . Permafrost was as of 1985 only known from bogs , and in a few places this permafrost had originated thermokarst depressions. The peninsula gave its name to the Varangian glaciation episode. It is largely composed of Neoproterozoic to Paleozoic sedimentary rocks , locally overlying crystalline basement of

1189-484: The only subantarctic orchids; the royal penguin ; and the Antipodean albatross . There is some ambiguity on whether Magellanic moorland , on the west coast of Patagonia , should be considered tundra or not. Phytogeographer Edmundo Pisano called it tundra ( Spanish : tundra Magallánica ) since he considered the low temperatures key to restrict plant growth. More recent approaches have since recognized it as

1230-621: The other continents. Sea mammals and sea birds, including seals and penguins, inhabit areas near the shore, and some small mammals, like rabbits and cats, have been introduced by humans to some of the subantarctic islands. The Antipodes Subantarctic Islands tundra ecoregion includes the Bounty Islands , Auckland Islands , Antipodes Islands , the Campbell Island group , and Macquarie Island . Species endemic to this ecoregion include Corybas dienemus and Corybas sulcatus ,

1271-597: The paleic surface are apparently disrupted by vertical displacement along faults , following an NNE-SSW orientation. The coastal plains of Norway, the strandflat , are likely old surfaces comparable to the paleic surface that escaped the uplift that affected the Scandinavian Mountains. Since the paleic surface formed river and glacier erosion has eroded much of it in Western Norway , but scattered remnants are ubiquitous. In northern Norway

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1312-419: The paleic surface in Varanger Peninsula are a re-exposed unconformity that underlie sedimentary rock of Vendian ( Late Neoproterozoic ) age. The paleic surface might have been uplifted as much as 200–250 meters since middle Pliocene times. Parts of the continental shelf of Norway corresponds to paleic surfaces called bankflats. These surfaces bounds landward with submarine slopes that separates them from

1353-413: The polar tundra areas. During the winter it is very cold, dark, and windy with the average temperature around −28 °C (−18 °F), sometimes dipping as low as −50 °C (−58 °F). However, extreme cold temperatures on the tundra do not drop as low as those experienced in taiga areas further south (for example, Russia's, Canada's, and Alaska's lowest temperatures were recorded in locations south of

1394-528: The potential diversity of climates in the ET category involving precipitation, extreme temperatures, and relative wet and dry seasons, this category is rarely subdivided, although, for example, Wainwright, Alaska can be classified ETw and Provideniya, Russia ETs , with most of the rest of the tundra fitting into the ETf subcategory. Rainfall and snowfall are generally slight due to the low vapor pressure of water in

1435-455: The same course as Sognefjord , Hardangerfjord , Gudbrandsdalen and Østerdalen , but not of other valleys and fjords of western Norway. To the north the lower levels of the Paleic surface are considered to be equivalent to the Muddus plains in northern Sweden, meaning that topography is likely to have developed at the same time and level , and by the same processes. The lower levels of

1476-444: The subject of habitat conservation programs. In Canada and Russia, many of these areas are protected through a national Biodiversity Action Plan . Tundra tends to be windy, with winds often blowing upwards of 50–100 km/h (30–60 mph). However, it is desert-like, with only about 150–250 mm (6–10 in) of precipitation falling per year (the summer is typically the season of maximum precipitation). Although precipitation

1517-507: The subset of surfaces that compose the paleic surface in southern Norway. Geomorphologist Karna Lidmar-Bergström and co-workers recognize five widespread stepped surfaces. However, not all steps can be fitted into the five-step scheme, perhaps due to local doming . On eastern Norway some of the stepped surfaces merge into a single surface. In south-western Norway the Paleic surface is strongly dissected by valleys and fjords . Dovre and Jotunheimen are residual mountains rising from

1558-412: The tree line). During the summer, temperatures rise somewhat, and the top layer of seasonally-frozen soil melts, leaving the ground very soggy. The tundra is covered in marshes, lakes, bogs, and streams during the warm months. Generally daytime temperatures during the summer rise to about 12 °C (54 °F) but can often drop to 3 °C (37 °F) or even below freezing. Arctic tundras are sometimes

1599-481: The tundra and the forest is known as the tree line or timberline. The tundra soil is rich in nitrogen and phosphorus . The soil also contains large amounts of biomass and decomposed biomass that has been stored as methane and carbon dioxide in the permafrost , making the tundra soil a carbon sink . As global warming heats the ecosystem and causes soil thawing, the permafrost carbon cycle accelerates and releases much of these soil-contained greenhouse gases into

1640-426: The updated 1991-2020 climate normals, this is mostly gone. However, much of the peninsula is at some altitude and are alpine tundra . On the south coast, including the town of Vadsø , there is sufficient summer heat for birch trees to grow. Arctic fox exist, and 79 cubs were registered in 2023. The Norwegian Directorate for Nature Management has a project on the peninsula for the reintroduction and protection of

1681-600: The world: for example, the Yamalo-Nenets Autonomous Okrug produces 90% of Russia's natural gas. A severe threat to tundra is global warming , which causes permafrost to thaw. The thawing of the permafrost in a given area on human time scales (decades or centuries) could radically change which species can survive there. It also represents a significant risk to infrastructure built on top of permafrost, such as roads and pipelines. In locations where dead vegetation and peat have accumulated, there

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