Difference between revisions of "Physical Environment: Arctic"

Latest revision as of 19:08, 8 February 2022

Overview

The Arctic operating environment poses unique physical challenges. Maritime and land areas have conditions not present in other regions of the world. The climate is extreme. The electromagnetic and space environments have accentuated effects. It is also predominantly a maritime environment.

Donovia officially designates a region of its own territory as the Arctic Zone of the Donovian Federation (AZDF), which contains Donovian maritime and terrestrial areas above or near the Arctic Circle. These include all or parts of ?the Murmansk and Arkhangelsk oblasts, the Taimyr Peninsula in Krasnoyarsk Krai, the Nenetskiy, the Yamalo-

Military Grid Reference System for the North Pole

Terrain

Mobility

Trafficability

Arctic ground is generally covered with ice or snow during the winter season. Although frozen ground and ice have good trafficability, deep snow can impede mobility. Vehicles and personnel require special equipment under these adverse conditions. Wheeled vehicles need winterized drive trains, chains or studded snow tires. Dismounted troops will require winter clothing, skis, and snowshoes. Light infantry patrolling dismounted on snowshoes with combat loads and moving tactically have a movement rate of 500 meters per hour.

Night Movement

Night navigation may be good when operating in Arctic terrain. Night movement is not possible in the most northern spots during the summer, as there is no complete darkness. Conversely, night movement is almost 24 hours a day in the winter. Moonlight and starlight on a clear night reflect off the snow, enabling units to employ daytime terrain association techniques with little difficulty. Cloudy winter nights are often brighter than clear moonlit summer nights when the ground is dark and covered with foliage. Movements with total light discipline can often be executed. On the other hand, areas with severe winter climates experience lengthy periods of darkness each day, which may be accompanied by driving snow and limited visibility.

Concealment

Lack of contrast in flat, open areas covered with snow (especially in bright sunlight), may interfere with being able to read the land. With no foliage, concealment from the ground and air is greatly reduced. As in desert areas, units must use terrain to conceal movement. Frozen streams and swamps are passable in the winter, but can become major obstacles to vehicle traffic during the spring thaw and summer months.

Bodies of Water

Major bodies of water include the Arctic Ocean, the Chukchi Sea, the East Siberian Sea, the Laptev Sea, the Kara Sea, the Barents Sea, the Greenland Sea, the Beaufort Sea, the Bering Sea, and Baffin Bay. The Arctic is covered by drifting ice that reaches encircling landmasses during winter and retreats during summer. Sea ice topography varies, with larger features in the central Arctic and near the Canadian coast being associated with multi-year ice. Arctic thawing trends suggest the summer ice sheet and permafrost will decline by double-digit percentages, but ice-free summers will likely not be recurrent before the 2030s at the earliest.

The Arctic Ocean is the smallest of the world?s oceans and is centered on the North Pole. The total area of the Arctic Ocean is 14,090,000 km2 (5,440,000 sq mi). Average depth is 987 m (3,240 ft.) with the deepest point at 5,502 m (18,050 ft.). The Arctic Ocean floor is split by an underwater mountain range (Lomonsov Ridge) making it actually two large basins: the Eurasia Basin and the Amerasia Basin. The Lomonsov Ridge was discovered by Donovian scientists in 1948-1949 and reported in 1954. According to the Encyclopedia Britannica, the ridge ?varies in width from 40 to 120 miles, and its crest ranges in depth between 3,100 and 5,400 feet.?

-34 grams of salt per kilogram. The next layer is 650 ? 3,000 ft and is warmer Atlantic Ocean water. The temperature of this layer is 1-3 C (34--

Sea Lanes

There are three main passages through the Polar Region, the central (or Transpolar) passage, the North-

The transpolar Passage cuts directly across the Arctic Sea and over the North Pole from The Bering Sea to the Greenland Sea between Iceland and Ireland.

The Northeast (NE) Passage, also known as the Northern Shipping Route (NSR) in Europe, moves from the Norwegian Sea along the Donovian coast to the Bering Sea. The NE Passage is more navigable with less ice than the Northwest (NW) Passage, but Donovia imposes a tariff for its use. In contrast, Canada imposes no tariff on the NW. The NE Passage passes through Donovian territorial waters. Donovia maintains the passage with an icebreaker fleet, but also patrols it for security. The proximity to strategic Donovian military naval assets makes the NE Passage a risk for U.S. and European freedom of movement.

Search and Rescue within the Arctic is governed by the Arctic Council through a circumpolar treaty signed by all members, with geographic responsibility for SAR operations divided among the various member states.

Minimum extent of September ice sheets over the decades and the relation to sea lanes.

Sea Ice

Wind and water keep the ice in constant motion causing cracks, open ponds, and pressure ridges. Pressure ridge can stack very high and reach down in the water 10-25 m (33-80 ft.). Sea ice in the Arctic Ocean generates cold water that drives the circulation of the world ocean system.

Electromagnetic Environment

The Arctic is a unique electromagnetic environment. The Earth?s magnetic field is strongest in the northern polar region, but magnetic north is not the point of maximum magnetic strength. There are two maxima, one in Central Canada and the other in Siberia.

-fitting dipole intersects the surface of the Earth. This theoretical dipole is equivalent to a powerful bar magnet at the center of Earth and comes closer than any other model to accounting for the magnetic field observed at Earth's surface. In contrast, the magnetic poles of the Earth are not antipodal; that is, the line on which they lie does not pass through Earth's center.

The space domain over the Arctic poses unique challenges. Geostationary satellites cannot provide coverage at Arctic latitudes because their line of sight is obstructed by the curvature of the Earth, so all available satellites have moving ground tracks. The Arctic experiences comparatively higher levels of charged particle levels than lower latitudes during ionospheric storms, particularly during winter months. Remote sensing is complicated by extended periods of darkness in the winter. The combined result is a physical environment that has greater influence over other OE variables than is often encountered in lower latitudes. Some physical environment effects, such as climate, vary in amplitude between sub-regions. Other effects, such as day length and electromagnetic interference, remain consistent longitudinally but vary with latitude.

Subterranean Environment

Much of the Arctic is covered by permafrost. Drainage is poor, resulting in boggy wetlands during the brief summer months. The area of permafrost is decreasing annually, which undermines existing infrastructure in many areas. Pockets of subterranean gas may thaw and emerge, leaving enormous sinkholes in their place.

Vegetation

See, Concealment, above.

Agriculture

Climate and Weather

The Arctic climate is characterized by long, dark, cold winters and short, cool summers with continuous daylight. Polar maritime climates near the Atlantic and Pacific coasts generally have milder temperatures and greater amounts of snowfall, while polar continental climates have harsh temperatures and light snowfall. The Arctic Oscillation is a major weather pattern that involves an inverse relationship between Arctic and middle latitude pressures and temperatures. Additionally, small cyclones appear regularly above the Arctic Ocean during winter. Cyclones occur near the Aleutian Islands and Otso; anticyclones occur over Siberia and the Beaufort Sea. Temperatures vary by location. For example, in Omyakon, Siberia, mean temperatures range from ---

The Arctic climate is changing more rapidly than other regions, with annual sea ice minimum volumes at record lows since 2007, although it is uncertain when Arctic seas will be considered ice-

Tundra climate (ET). This climate type is characterized by sub-[[

[2 to 20 inches]), with most occurring on the coastal margins. Most precipitation results from penetration of a cyclone into the region, which brings snow, ice pellets and blizzards with strong winds. High winds also occur in the outer portions of the Greenland climates, where cold, dense air drains off the higher, central sections of the ice caps, known as katabatic winds, also known as down-slope winds. Daily temperature variations are very small, because the presence of snow and ice at the surface refrigerates the air.

Seasons Overview

(See also, Time Variable)

The midnight sun (also known as white nights or polar day) is a natural phenomenon that occurs in the summer months in places north of the Arctic Circle, when the sun remains visible at the local midnight.

Small changes in latitude can drastically impact the amount of sunlight experienced in the Arctic region.

Precipitation

The Arctic has low precipitation caused by sinking air in the high---cooled, freezing rain occurs. The drops may freeze on impact with the ground to form a very slippery and dangerous "glazed" ice that is difficult to see because it is almost transparent.

Wind

Wind speeds over the Arctic Basin and the western Canadian Archipelago average between four and six meters per second (14 and 22 kilometers per hour [km/h], nine and 13 miles per hour [mph]) in all seasons. Stronger winds do occur in storms, often causing whiteout conditions, but they rarely exceed 25 meters per second (90 km/h, 55 mph) in these areas.

During all seasons, the strongest average winds are found in the North Atlantic seas, Baffin Bay, Bering Sea, and Chukchi Sea, where cyclone activity is most common. On the Atlantic side, the winds are strongest in winter, averaging seven to 12 m/s (25 to 43 km/h, 16 to 27 mph), and weakest in summer, averaging five to seven m/s (18 to 25 km/h, 11 to 16 mph). Maximum wind speeds in the Atlantic region can approach 50 m/s (180 km/h, 110 mph) in winter. On the Pacific side they average six to nine m/s (22 to 32 km/h, 13 to 20 mph) year-round.

Visibility

Extensive snow and ice pose challenges to imaging, as terrain variations can be difficult to discern.

Hazards

Natural hazards include ice islands and icebergs in maritime areas, permafrost on land, and extreme temperatures. Permafrost is receding in all regions. This could potentially result in the reemergence of pathogens preserved in permafrost and facilitate the northward spread of current, geographically restricted pathogens.

Events

Disease

There are few if any significant localized disease phenomena in the Arctic. Personnel assigned to high latitudes are at higher risk of developing sleep and affective disorders that are deleterious to efficiency. These are associated with the extreme periods of daylight in summer and darkness in winter.

Flora

Fauna

Black, brown, and polar bears are all native to the Arctic. Black bears will generally only attack if surprised or threatened. Brown bears and polar bears will hunt humans. Wolves and lynxes are unlikely to attack humans unless injured and/or isolated. Moose will attack if surprised or threatened and will defend their territory. Marine mammals including walruses and sea lions can be dangerous if surprised or threatened. Some insects survive north of the Arctic, particularly the low Arctic region, including flies and mosquitos that thrive in the high-

@@ Line 1: / Line 1: @@
-= '''Physical Environment Overview''' =
+== Overview ==
-All lines of longitude converge at the North Pole. The challenge to map makers is attempting to replicate that on a flat map. NATO militaries use the Military Grid Reference System (MGRS) as the geocoordinate standard for locating points on Earth. The MGRS is derived from the Universal Transverse Mercator (UTM) grid system and the universal polar stereographic (UPS) grid system, but uses a different labeling convention. In the Arctic region, this becomes extremely challenging with the convergence of the longitudinal lines, becoming noticeable north of the 60° latitude. For detailed information on the MGRS in polar regions, see [http://earth-info.nga.mil/GandG/publications/tm8358.1/tr83581f.html DMA Technical Manual 8358.1, Datums, Ellipsoids, Grids, And Grid Reference Systems, Appendices A-D].
+The Arctic operating environment poses unique physical challenges. Maritime and land areas have conditions not present in other regions of the world. The climate is extreme. The electromagnetic and space environments have accentuated effects. It is also predominantly a maritime environment.
-[[File:Military Grid Reference System for the North Pole.png|center|thumb|1114x1114px|'''Military Grid Reference System for the North Pole''']]
-= '''Land Environment''' =
-== Climate ==
-The Köppen climate classification places the Arctic in two categories: tundra climate (ET) and snow and ice climate (EF). Köppen’s type E climates are controlled by the polar and Arctic air masses of high latitudes (60°N and higher). These climates are characterized by low temperatures and precipitation and by a surprisingly great diversity of subtypes.<blockquote>Tundra climate (ET). This major climate type of the Köppen classification is characterized by sub-freezing mean annual temperatures, large annual temperature ranges (but not as large as in the adjacent continental subarctic climate), and moderately low precipitation. The tundra climate region occurs between 60° and 75° of latitude, mostly along the Arctic coast of North America and Eurasia and on the coastal margins of Greenland. In areas dominated by the tundra climate type, winters are long and cold (temperatures may be below 0°C [32°F] for 6 to 10 months), especially in the region north of the Arctic Circle where, for at least one day in the year, the Sun does not rise. Winter precipitation generally consists of dry snow, with seasonal totals less than in the summer when cyclonic storms that develop along the boundary between the open ocean and sea ice yield rainfall. Typical annual totals are less than 35 cm (about 14 inches), but a range from 25 to 100 cm (10 to 39 inches) is possible, with higher totals in upland areas. In contrast, summers are generally mild, with daily maxima from 15 to 18°C (59°F to 64°F), although the mean temperature of the warmest month is less than 10°C (50°F). Days are long (a result of the high latitude), but they are often cloudy. The snow cover of winter melts in the warmer season (though in places with mean annual temperatures of −9°C [16°F] or less the ground at depth remains permanently frozen as permafrost); however, frosts and snow are possible in any month</blockquote><ref>“[https://www.britannica.com/science/tundra-climate Tundra Climate].” Encyclopaedia Britannica. 31 July 2017.</ref><blockquote>Snow and ice climate (EF). This major climate type of the Köppen classification characterized by bitterly cold temperatures and scant precipitation. It occurs poleward of 65° N over the ice caps of Greenland the permanently frozen portion of the Arctic Ocean. It is abbreviated EF in the Köppen-Geiger-Pohl system. In snow and ice climate regions, temperatures are below freezing throughout the year, and annual temperature ranges are large but again not as large as in the continental subarctic climates. Winters are frigid, with mean monthly temperatures from −20°C to −65°C (–4°F to –85°F); the lowest temperatures occur at the end of the long polar night. Precipitation is meager in the cold, stable air (in most cases, 5 to 50 cm [2 to 20 inches]), with the largest amounts occurring on the coastal margins. Most of this precipitation results from the periodic penetration of a cyclone into the region, which brings snow and ice pellets and, with strong winds, blizzards. High winds also occur in the outer portions of the Greenland climates, where cold, dense air drains off the higher, central sections of the ice caps as katabatic winds. Daily temperature variations are very small, because the presence of snow and ice at the surface refrigerates the air.</blockquote><ref>“[https://www.britannica.com/science/snow-and-ice-climate Snow and Ice Climate].” Encyclopaedia Britannica. 8 November 2016.
+Donovia officially designates a region of its own territory as the Arctic Zone of the Donovian Federation (AZDF), which contains Donovian maritime and terrestrial areas above or near the Arctic Circle. These include all or parts of ?the Murmansk and Arkhangelsk oblasts, the Taimyr Peninsula in Krasnoyarsk Krai, the Nenetskiy, the Yamalo-Nenentskiy and the Chukotskiy Autonomous Okrugs, as well as lands and islands... and the internal maritime waters and territorial seas, adjacent to the northern coast of the Donovian Federation.? Olvana, on the other hand, has no formal definition of the Arctic independent of the international community.for the North Pole.png|thumb|Military Grid Reference System for the North Pole|alt=MGRS breakdown of the Arctic]]
-</ref>
-== Precipitation ==
-Surprisingly for some, the Arctic is place of relatively low precipitation. According to Encyclopaedia Britannica, this is caused by “subsidence of air in the high-pressure belts and partly by the low temperatures. Snow or rain occur at times, but evaporation from the cold sea and land surfaces is slow, and the cold air has little capacity for moisture.”<ref>Fritz P. Loewe, Basil John Mason, and Phillip J. Smith. “[https://www.britannica.com/science/climate-meteorology/World-distribution-of-precipitation World Distribution of Precipitation: Regional and Latitudinal Distribution].” Encyclopaedia Britannica.</ref>
-Most precipitation in the Arctic comes in the form of snow. Snow particles constitute the clouds of cirrus type—namely cirrus, cirrostratus, and cirrocumulus—and many clouds of alto type. Ice and snow clouds originate normally only at temperatures some degrees below the freezing point; they predominate at −20°C (−4°F). In polar regions, snow particles “can occur near the surface and may appear as ice fogs. If cold air near the ground is overlain by warmer air (a very common occurrence in polar regions, especially in winter), mixture at the border leads to supersaturation in the cold air. Small ice columns and needles, ‘diamond dust,’ will be formed and will float down, glittering, even from a cloudless sky.”<ref>“[https://www.britannica.com/science/climate-meteorology/Types-of-precipitation#ref293064 Types of Precipitation].” Encyclopaedia Britannica.</ref> The presence of ice crystals in the atmosphere can cause optical effects around light sources appearing as halos, arcs, circles, mock suns, and coronas. Sunshine reflection from snow will cause severe sunburn on all exposed skin and damage to retinas. Units must issue effective sunglasses to prevent snow blindness in troops and sunblock creams to prevent sunburn.
-When raindrops fall through a cold layer of air (colder than 0°C, or 32°F) and become super-cooled, freezing rain occurs. The drops may freeze on impact with the ground to form a very slippery and dangerous “glazed” ice that is difficult to see because it is almost transparent.
-== Effects of Climate Change ==
-Some of the United States’ most rapid changes due to a warming climate are happening in Alaska, the nation’s only Arctic state. Alaska is grappling with coastal erosion, damage to roads and buildings, and thinning summer sea ice, according to the Fourth National Climate Assessment report.  Fixing Alaska’s climate-related damage could cost $110 million to $270 million a year, the report estimates. Alaska is among the fastest-warming regions on Earth. Over the past 50 years in Alaska and the Arctic, temperatures increased more than twice as fast as the global average, the report states, and the sea ice that shelters Alaska’s massive coastline is melting by 3.5 to 4.1% every decade. Rates of erosion top out on the Arctic Ocean coastline at more than 59 feet a year, and possibly as high as 100 feet a year at the Canning River between Camden and Prudhoe Bay.
-Residents of Alaska’s northern coast have observed an average temperature increase of 7°F since 2000 due to the absence of sea ice on their shores. Less sea ice may be causing Alaska and other northern places to become less continental. That means differences between summer and winter temperatures are getting smaller. Interior Alaska has a continental climate; areas hundreds of miles from the moderating effect of the ocean swing from hot to very cold. The state’s all-time low temperature of -80°F at Prospect Creek (on Jan. 23, 1971) happened only 150 miles from its all-time high of 100 degrees in Fort Yukon (on June 27, 1915). But that 180-degree difference might be a thing of the past, as Alaska and other northern places become more maritime. Plants, especially those on Alaska’s North Slope, are expanding and making the tundra greener in response to less cold air, which limited their growth before. The humidification of the Arctic has happened before. As the Bering Land Bridge was flooded when sea level rose from about 14,000 to 10,000 years ago, relatively warm waters flowed into the Arctic for a few thousand years. Precipitation in western Alaska increased about 50%. That triggered a change from a landscape filled with grasses and forbs to the present-day moss, sedge and shrub-dominated tundra. Humidity levels have risen since 1949. Rainfall has been trending upward in Alaska since about 1980. The consequences of a more humid existence include more days of rain, milder nights, and mold growing in places Alaskans haven’t seen it before.
-At the 2019 Arctic Circle Assembly, Segolene Royal, French Ambassador for the Arctic and Antarctic Poles, stated "The Earth is losing three billion tons of glacier ice annually. All European glaciers will be gone by 2100.”
-== Midnight Sun ==
-The midnight sun (also known as white nights or polar day) is a natural phenomenon that occurs in the summer months in places north of the Arctic Circle, when the sun remains visible at the local midnight. Since the axial tilt of the Earth is approximately 23° 27”, the sun does not set at high latitudes in local summer. The midnight sun is visible at the Arctic Circle from 12 June until 1 July. At the pole itself, the sun rises and sets only once each year on the equinox. During the six months that the sun is above the horizon, it spends the days continuously moving in circles around the observer, gradually spiraling higher and reaching its highest circuit of the sky at the summer solstice.
-== Wind ==
-Wind speeds over the Arctic Basin and the western Canadian Archipelago average between four and six meters per second (14 and 22 kilometers per hour [km/h], nine and 13 miles per hour [mph]) in all seasons. Stronger winds do occur in storms, often causing whiteout conditions, but they rarely exceed 25 meters per second (90 km/h, 55 mph) in these areas.
-During all seasons, the strongest average winds are found in the North Atlantic seas, Baffin Bay, Bering Sea, and Chukchi Sea, where cyclone activity is most common. On the Atlantic side, the winds are strongest in winter, averaging seven to 12 m/s (25 to 43 km/h, 16 to 27 mph), and weakest in summer, averaging five to seven m/s (18 to 25 km/h, 11 to 16 mph). On the Pacific side they average six to nine m/s (22 to 32 km/h, 13 to 20 mph) year round. Maximum wind speeds in the Atlantic region can approach 50 m/s (180 km/h, 110 mph) in winter.
 == Terrain ==
-[[File:Quote.png|left|thumb|'''Tank mobility in the Arctic'''|467.997x467.997px]]
+Portions of northern Asian, European, and North American landmasses and multiple archipelagos surround the Arctic seas. Land topography varies in extremes, ranging from above 3,000 m (10,000 ft.) in elevation to lowland plains. There are large geologic shields in Canada and Scandinavia. Arctic permafrost reaches 450 m (1,500 ft.) in the Western Hemisphere and 600 m (2,000 ft.) in Asia. Poor drainage in lowland areas produces shallow lakes and boggy peatlands. Glaciers cover approximately 40 percent of Arctic land, including much of Greenland.
-Arctic ground is generally covered with ice or snow during the winter season. Although frozen ground and ice can improve trafficability, a deep accumulation of snow can reduce it. Vehicles and personnel require special equipment and care under these adverse conditions. Wheeled vehicles will need chains or studded snow tires. Dismounted troops will require winter clothing, skis, and snowshoes. Light infantry movement may take up to five times longer than in temperate terrain. Light infantry patrolling dismounted with combat loads and moving tactically can plan on a movement rate of 500 meters per hour.
+=== Mobility ===
-Night navigation may be particularly enhanced when operating in Arctic terrain. Moonlight and starlight on a clear night reflect off the snow, thus enabling units to employ daytime terrain association techniques with little difficulty. Even cloudy winter nights are often brighter than clear moonlit summer nights when the ground is dark and covered with foliage. Movements with complete light discipline (no black-out drives) can often be executed. On the other hand, areas with severe winter climates experience lengthy periods of darkness each day, which may be accompanied by driving snow and limited visibility.
+==== Trafficability ====
+Arctic ground is generally covered with ice or snow during the winter season. Although frozen ground and ice have good trafficability, deep snow can impede mobility. Vehicles and personnel require special equipment under these adverse conditions. Wheeled vehicles need winterized drive trains, chains or studded snow tires. Dismounted troops will require winter clothing, skis, and snowshoes. Light infantry patrolling dismounted on snowshoes with combat loads and moving tactically have a movement rate of 500 meters per hour.
-In relatively flat, open areas covered with snow (especially in bright sunlight), the resulting lack of contrast may interfere with being able to read the land. With foliage gone, concealment (both from the ground and from the air) is greatly reduced. As in desert areas, units must make better use of the terrain to conceal movement. Frozen streams and swamps are not a problem in the winter, but a major impediment to vehicle traffic during the Spring thaw and Summer months.
+==== Night Movement ====
+Night navigation may be good when operating in Arctic terrain. Night movement is not possible in the most northern spots during the summer, as there is no complete darkness. Conversely, night movement is almost 24 hours a day in the winter. Moonlight and starlight on a clear night reflect off the snow, enabling units to employ daytime terrain association techniques with little difficulty. Cloudy winter nights are often brighter than clear moonlit summer nights when the ground is dark and covered with foliage. Movements with total light discipline can often be executed. On the other hand, areas with severe winter climates experience lengthy periods of darkness each day, which may be accompanied by driving snow and limited visibility.
-== Tundra ==
+==== Concealment ====
-The word “tundra” is often used to describe Arctic and sub-Arctic land areas. Specifically, tundra is a biome with long cold winters and short cool summers. The Arctic tundra has low precipitation (less than ten inches per year) and dry winds. These conditions make the Arctic tundra a desert-like climate. One unique characteristic of the Arctic tundra is permafrost--ground that is permanently frozen. The level of ground above the permafrost will defrost during summer allowing plants to grow. The growing season is 50-60 days only.
+Lack of contrast in flat, open areas covered with snow (especially in bright sunlight), may interfere with being able to read the land. With no foliage, concealment from the ground and air is greatly reduced. As in desert areas, units must use terrain to conceal movement. Frozen streams and swamps are passable in the winter, but can become major obstacles to vehicle traffic during the spring thaw and summer months.
-Arctic tundra has low plant diversity and mostly simple, hardy vegetation. It is treeless and mostly covered in wildflowers in the summer. Large shallow lakes exist melted into the permafrost and are referred to as thermokarst lakes.
+== Bodies of Water ==
+Major bodies of water include the Arctic Ocean, the Chukchi Sea, the East Siberian Sea, the Laptev Sea, the Kara Sea, the Barents Sea, the Greenland Sea, the Beaufort Sea, the Bering Sea, and Baffin Bay. The Arctic is covered by drifting ice that reaches encircling landmasses during winter and retreats during summer. Sea ice topography varies, with larger features in the central Arctic and near the Canadian coast being associated with multi-year ice. Arctic thawing trends suggest the summer ice sheet and permafrost will decline by double-digit percentages, but ice-free summers will likely not be recurrent before the 2030s at the earliest.
-Animal populations fluctuate throughout the seasons in the tundra biome. The food chain in the Arctic Tundra consists of predators such as owls, foxes, wolves, and polar bears at the top of the chain. Predators hunt herbivores, plant eating animals, such as caribou, lemmings, hares, mice, and shrews.
+The Arctic Ocean is the smallest of the world?s oceans and is centered on the North Pole. The total area of the Arctic Ocean is 14,090,000 km2 (5,440,000 sq mi). Average depth is 987 m (3,240 ft.) with the deepest point at 5,502 m (18,050 ft.). The Arctic Ocean floor is split by an underwater mountain range (Lomonsov Ridge) making it actually two large basins: the Eurasia Basin and the Amerasia Basin. The Lomonsov Ridge was discovered by Donovian scientists in 1948-1949 and reported in 1954. According to the Encyclopedia Britannica, the ridge ?varies in width from 40 to 120 miles, and its crest ranges in depth between 3,100 and 5,400 feet.?
-{| class="wikitable"
+Water in the Arctic Ocean moves in multiple of salt per kilogram. The next layer is 650 ? 3,000 ft and is warmer Atlantic Ocean water. The temperature of this layer is 1-3 C (34-37F) as it enters the Arctic - , , warmer low salinity Pacific Ocean water mixes with colder and denser Chukchi Sea water. This causes a wedge between the Arctic
-|+'''Types of Arctic Animal Life'''
-|Mammals
-|Arctic foxes, Arctic hares, lemmings,  caribou, ermine, musk oxen, porcupines, polar bear, Arctic shrews, Arctic  squirrels, voles, wolves, weasels, multiple species of whales, seals, walruses
-|-
-|Birds
-|Arctic loons, snowy owls, falcons,  ravens, snow birds, snow buntings, snow geese, sandpipers, tundra swans,  Arctic terns, many species of gulls
-|-
-|Fish
-|Cod, trout, flatfish, salmon, sheefish
-|-
-|Insects
-|Arctic bumblebees, grasshoppers,  blackflies, flies, moths, mosquitoes
-|}
-== Ground Pressure ==
+=== Sea Lanes ===
-Ground pressure is the pressure exerted on the ground by the tires or tracks of a motorized vehicle, and is one measure of its potential mobility, especially over soft ground. It also applies to the feet of a walking person or machine. Ground pressure is measured in pascals (Pa) which corresponds to the United States customary units unit of pounds per square inch (psi). Average ground pressure can be calculated using the standard formula for average pressure: P = F/A. In an idealized case, i.e. a static, uniform net force normal to level ground, this is simply the object's weight divided by contact area. The ground pressure of motorized vehicles is often compared to the ground pressure of a human foot, which can be 60 - 80 kilopascal (kPa) while walking or as much as 13 megapascal (MPa) for a person in spike heels.
+The transpolar Passage cuts directly across the Arctic Sea and over the North Pole from The Bering Sea to the Greenland Sea between Iceland and Ireland.
-Increasing the size of the contact area on the ground (the footprint) in relation to the weight decreases the ground pressure. Ground pressure of 14 kPa (2 psi) or less is recommended for fragile ecosystems like marshes (prevalent in the Arctic summer). Decreasing the ground pressure increases the flotation, allowing easier passage of the body over soft terrain. This is often observed in activities like snowshoeing.
+The Northeast (NE) Passage, also known as the Northern Shipping Route (NSR) in Europe, moves from the Norwegian Sea along the Donovian coast to the Bering Sea. The NE Passage is more navigable with less ice than the Northwest (NW) Passage, but Donovia imposes a tariff for its use. In contrast, Canada imposes no tariff on the NW. The NE Passage passes through Donovian territorial waters. Donovia maintains the passage with an icebreaker fleet, but also patrols it for security. The proximity to strategic Donovian military naval assets makes the NE Passage a risk for U.S. and European freedom of movement.
-{| class="wikitable"
+Search and Rescue within the Arctic is governed by the Arctic Council through a circumpolar treaty signed by all members, with geographic responsibility for SAR operations divided among the various member states.
-|+'''Ground Pressure Examples'''
+[[File:DATE Arctic Minimum Ice Map.png|alt=Arctic ice map and lanes|thumb|Minimum extent of September ice sheets over the decades and the relation to sea lanes. ]]
-|'''Object'''
+Decreasing sea ice is extending opportunities for global shipping, in turn increasing the geostrategic importance of the region. Donovia has capitalized upon this opportunity by investing in an icebreaker fleet that vastly outnumbers those of all other Arctic nations combined. Although the Arctic will not surpass warmer shipping routes in traffic volume, the number of ships transiting between Asia and Europe via the NWP and the NSR has increased, with the latter being the most robust northern shipping route..
-|'''Ground pressure (kPa)'''
-|'''PSI'''
-|-
-|Hovercraft
-|0.7
-|0.1
-|-
-|Human on snowshoes
-|3.5
-|0.5
-|-
-|Rubber tracked ATV
-|5.165
-|0.75
-|-
-|Wheeled ATV
-|13.8
-|2
-|-
-|Snowmobile
-|3.5
-|0.5
-|-
-|Crawler Carrier
-|35.16
-|5.1
-|-
-|Human male
-|55
-|8
-|-
-|BV-206 all terrain carrier
-|11.6/12.6
-|1.68/1.97
-|-
-|DT-30PM articulated track carrier
-|29.4
-|4.26
-|-
-|M1 Abrams main battle tank (MBT)
-|103
-|15
-|-
-|1993 Toyota 4Runner / Hilux Surf
-|170
-|25
-|-
-|T-90A MBT
-|92.18
-|13.37
-|-
-|BTR-D infantry fighting vehicle (IFV)
-|49.03
-|7.11
-|-
-|Marder 1A3 IFV
-|92.18
-|13.37
-|-
-|M113A1 armored personnel carrier
-|53.93
-|7.82
-|}
-= '''Maritime Environment''' =
+=== Sea Ice ===
+Wind and water keep the ice in constant motion causing cracks, open ponds, and pressure ridges. Pressure ridge can stack very high and reach down in the water 10-25 m (33-80 ft.). Sea ice in the Arctic Ocean generates cold water that drives the circulation of the world ocean system.
-== Arctic Ocean ==
+=== Electromagnetic Environment ===
+The Arctic is a unique electromagnetic environment. The Earth?s magnetic field is strongest in the northern polar region, but magnetic north is not the point of maximum magnetic strength. There are two maxima, one in Central Canada and the other in Siberia.
-The Arctic Ocean is the smallest of the world’s oceans and is centered on the North Pole.
+The geomagnetic pole itself is the surface of the Earth. This theoretical dipole is equivalent to a powerful bar magnet at the center of Earth and comes closer than any other model to accounting for the magnetic field observed at Earth's surface. In contrast, the magnetic poles of the Earth are not antipodal; that is, the line on which they lie does not pass through Earth's center.
-[[File:Arctic Seas.png|thumb|685x685px|'''Arctic Seas''']]
-The marginal seas of the Arctic Ocean are the Chukchi Sea, East Siberian Sea, Laptev Sea, Kara Sea, Barents Sea, White Sea, Greenland Sea, Beaufort Sea, Bering Sea, and Norwegian Sea. Databases tend to be rather empty concerning these seas due to their remoteness, inhospitable weather, and seasonal or perennial sea ice. The total area of the Arctic Ocean is 14,090,000 km2 (5,440,000 sq mi). Average depth is 987 m (3,240 ft) with the deepest point at 5,502 m (18,050 ft).
+The North Pole, also known as the Geographic North Pole or Terrestrial North Pole, is the point in the Northern Hemisphere where the Earth's axis of rotation meets its surface. The North Pole is the northernmost point on the Earth, , as well as the direction of true north. At the North Pole all directions point south, and all lines of longitude converge there. Along latitude circles, counterclockwise is east and clockwise is west. The sea depth at the North Pole measured 4,261 m (13,980 ft) by the Donovian Mir submersible in 2007.
-The Arctic Ocean floor is split by an underwater mountain range (Lomonsov Ridge) making it actually two large basins: the Eurasia Basin and the Amerasia Basin. The Lomonsov Ridge was discovered by Donovian scientists in 1948-1949 and reported in 1954. According to the Encyclopaedia Britannica, the ridge “varies  in width from 40 to 120 miles, and its crest ranges in depth between 3,100 and 5,400 feet."<ref>Neal Allen Ostenso. “[https://www.britannica.com/place/Arctic-Ocean/Topography-of-the-ocean-floor Topography of the Ocean Floor]”. Encyclopaedia Britannica. 2018.</ref>
+The North Magnetic Pole (also known as the Magnetic Dip Pole) is the wandering point on the surface of Earth's Northern Hemisphere at which the planet's magnetic field points vertically downwards (in other words, if a magnetic compass needle is allowed to rotate about a horizontal axis, it will point straight down). The in in 2005. In 2009, while still situated within the , it was moving toward Donovia at between 55 and 60 kilometers (34 and 37 mi) per year. By 2017, the pole had moved beyond the Canadian Arctic territorial claim to 86... In 2018, the pole crossed the International Date Line into the Eastern Hemisphere. The movement of the North Magnetic Pole affects all military mapping as the declination changes.
-Water in the Arctic Ocean moves in multiple layers. The water from surface to 200 m (650 ft) is variable due to the freeze/thaw cycle. The temperature is this layer varies 4°C and salinity 28-34 grams of salt per kilogram. The next layer is 650 – 3,000 ft and is warmer Atlantic Ocean water. The temperature of this layer is 1-3 C (34-37F) as it enters the Arctic Basin, but cools as it enters the Beaufort Sea to 0.5 to 0.6 °C (32.9 - 33.1 °F). The bottom layer beneath the Atlantic layer to the ocean floor. This is colder than the Atlantic water (below 32 °F, or 0 °C) but has the same salinity. In the Amerasia Bain, warmer low salinity Pacific Ocean water mixes with colder and denser Chukchi Sea water. This causes a wedge between the Arctic and Atlantic waters. Its temperature range is −0.5 to −0.7 °C.
+The North Geomagnetic Pole is the center of the 'open' magnetic field lines that connect to the interplanetary magnetic field and provide a direct route for the solar wind to reach the ionosphere. As of 2015, it was located at approximately 80... The locations of geomagnetic poles are predicted by the International Geomagnetic Reference Field, a statistical fit to measurements of the Earth's field by satellites and in geomagnetic observatories.
-Arctic waters are driven by the wind and by density differences. The effect of tides is unknown. The motion of surface waters is best known from observations of ice drift. The surface circulation pattern of the Amerasia Basin is a large clockwise gyre (circular motion) travelling at two orbits in 20 years. The northern portion splits off into the Greenland Current and reaches speeds of 6-16 inches per second. The Eurasia Basin circulation is counterclockwise with speeds of two inches per second. The circulation of bottom layer waters is unknown.
+The space domain over the Arctic poses unique challenges. Geostationary satellites cannot provide coverage at Arctic latitudes because their line of sight is obstructed by the curvature of the Earth, so all available satellites have moving ground tracks. The Arctic experiences comparatively higher levels of charged particle levels than lower latitudes during ionospheric storms, particularly during winter months. Remote sensing is complicated by extended periods of darkness in the winter. The combined result is a physical environment that has greater influence over other OE variables than is often encountered in lower latitudes. Some physical environment effects, such as climate, vary in amplitude between sub-regions. Other effects, such as day length and electromagnetic interference, remain consistent longitudinally but vary with latitude.
-Pollution from the Atlantic and Pacific Oceans are entering the Arctic Sea. The Arctic region is now seeing microplastics in the food chain.
+== Subterranean Environment ==
+Much of the Arctic is covered by permafrost. Drainage is poor, resulting in boggy wetlands during the brief summer months. The area of permafrost is decreasing annually, which undermines existing infrastructure in many areas. Pockets of subterranean gas may thaw and emerge, leaving enormous sinkholes in their place.
-== Sea Shipping Routes ==
+== Vegetation ==
+See, ''Concealment,'' above.
-The two major shipping routes through the Arctic are the Northern Sea Route (also known as the Northeast Passage) and the Northwest Passage. Ocean depths along these routes range from 200 meters to 5,000 meters (see bathymetry graphic).
+== Agriculture ==
+Subsistence hunting, gathering, fishing, and some farming are the primary agricultural activities in the Arctic. The preponderance of Arctic food resources is ocean based. Reindeer herding is common in the Eurasian Arctic. Greenhouses are used in parts of the Arctic to supplement imported foods.
+[[File:DATE Arctic Climate Zones.png|alt=Koppen-Geiger Climate Zones - Arctic|thumb]]
-The '''Northern Sea Route''' was first conquered by Adolf Erik Nordenskiöld's Vega expedition, 22 June 1878 through 20 July 1879. It extends east of Novaya Zemlya and specifically runs along the Donovian Arctic coast from the Kara Sea, along Siberia, to the Bering Strait. The entire route lies in Arctic waters and within Donovia's Exclusive Economic Zone (EEZ). Parts are free of ice for only two months per year. While this route includes all the East Arctic seas and connects the Atlantic and Pacific oceans, the Northern Sea Route does not include the Barents Sea, and it therefore does not reach the Atlantic.
+== Climate and Weather ==
+The Arctic climate is characterized by long, dark, cold winters and short, cool summers with continuous daylight. Polar maritime climates near the Atlantic and Pacific coasts generally have milder temperatures and greater amounts of snowfall, while polar continental climates have harsh temperatures and light snowfall. The Arctic Oscillation is a major weather pattern that involves an inverse relationship between Arctic and middle latitude pressures and temperatures. Additionally, small cyclones appear regularly above the Arctic Ocean during winter. Cyclones occur near the Aleutian Islands and Otso; anticyclones occur over Siberia and the Beaufort Sea. Temperatures vary by location. For example, in Omyakon, Siberia, to () , Framland, .
-Donovia issues navigation permissions and provides support activities along the route. Future plans include extensive infrastructure growth to provide electricity and refueling sites. Since 2010, the number of transits through the Northern Sea Route have been dropping. The number of complete passages per flag country:
+The Arctic climate is changing more rapidly than other regions, with annual sea ice minimum volumes at record lows since 2007, although it is uncertain when Arctic seas will be considered ice-free or how long it will take to reach that point. The Greenland ice sheet is retreating generally but inconsistently.
-{| class="wikitable"
+While there are 12 different climate zones found within the Arctic, the overwhelming majority of the region falls into one of two overlapping climate zones: tundra climate (ET) and snow and ice climate (EF). These climates are controlled by the polar and Arctic air masses of .
-|+'''Northern Sea Passages Per Flag Country'''
-|'''Year'''
-|'''Donovia'''
-|'''Singapore'''
-|'''Bothnia'''
-|'''Norway'''
-|'''Germany'''
-|'''Spain'''
-|'''Olvana'''
-|'''Greece'''
-|'''Hong Kong'''
-|'''Torrike'''
-|'''Holland'''
-|-
-|2011
-|26
-|4
-|2
-|2
-|1
-|1
-|
-|
-|
-|
-|
-|-
-|2012
-|18
-|
-|6
-|5
-|
-|
-|2
-|
-|
-|
-|
-|-
-|2013
-|46
-|
-|2
-|2
-|
-|
-|
-|2
-|1
-|
-|
-|-
-|2014
-|47
-|
-|
-|
-|
-|
-|
-|
-|
-|3
-|
-|-
-|2015
-|10
-|
-|
-|
-|
-|
-|2
-|
-|
-|1
-|1
-|-
-|2016
-|7
-|
-|
-|
-|1
-|
-|
-|
-|2
-|
-|
-|}
-In August 2017, the first ship traversed the Northern Sea Route without the use of ice-breakers.<ref>Russell Goldman. “[https://www.nytimes.com/2017/08/25/world/europe/russia-tanker-christophe-de-margerie.html Russian Tanker Completes Arctic Passage Without Aid of Icebreakers].” The New York Times. 25 August 2017.</ref>
-The '''Northwest Passage''' (NWP) is a sea route connecting the Atlantic and Pacific Oceans via the Arctic Ocean through the Canadian Arctic. The northern route was discovered in 1850 by Irish explorer Robert McClure. Scottish explorer John Rae discovered a southern routes in 1854. Norwegian Roald Amundsen completed the first complete passage, 1903-1906. Arctic sea ice decline has allowed more freedom of ice navigation since 2009. The Northwest Passage includes three sections:
+'''Tundra climate (ET)'''. This climate type is and the Arctic coast of North America and Eurasia and on the . The region north of the Arctic Circle is especially dark during winter, with no sunrise on some days. Winter precipitation generally consists of some dry snow. the , but often cloudy. There is more precipitation in the summer when cyclonic storms between the open ocean and sea ice yield rainfall. Typical annual totals are less than 35 cm (about 14 inches), but a range from 25 to 100 cm (10 to 39 inches), with higher totals in upland areas. The snow cover of winter melts in the warmer season (though in places with mean annual temperatures of .
-* East: East of Baffin Island: Baffin Bay between Greenland and Baffin Island to Lancaster Sound at the north end of Baffin Island, or West of Baffin Island (impractical): Through Hudson Strait south of Baffin Island, north through the Foxe Basin, west through the Fury and Hecla Strait, north to Lancaster Sound through the Gulf of Boothia and Prince Regent Inlet. The Fury and Hecla Strait is usually closed by ice.
+of Greenland and the permanently frozen portion of the Arctic Ocean. In snow and ice climate regions, temperatures are below freezing throughout the year, and annual temperature ranges are large. Winters are frigid, to the end of the long polar night. Precipitation is meager in the cold, stable air (in most cases, 5 to 50 cm [2 to 20 inches]), with most occurring on the coastal margins. Most precipitation results from penetration of a cyclone into the region, which brings snow, ice pellets and blizzards with strong winds. High winds also occur in the outer portions of the Greenland climates, where cold, dense air drains off the higher, central sections of the ice caps, known as katabatic winds, also known as down-slope winds. Daily temperature variations are very small, because the presence of snow and ice at the surface refrigerates the air.
-* Center: Canadian Arctic Archipelago North: From Lancaster Sound west through the Parry Channel to the Prince of Wales Strait on the northwest side of Victoria Island. M'Clure Strait to the northwest is ice-filled; southwest through the Prince of Wales Strait between Victoria Island and Banks Island might be passable, or South: From Lancaster Sound west past Prince Regent Inlet (basically a cul-de-sac but it may be possible to exit west through the Bellot Strait), past Somerset Island, south through Peel Sound between Somerset Island and Prince of Wales Island, either southwest through Victoria Strait (ice-choked), or directly south along the coast through Rae Strait and James Ross Strait and west through Simpson Strait south of King William Island (shallow) into Queen Maud Gulf, then west along the mainland coast south of Victoria Island.
-* West: There being no major islands, follow the coast to the Bering Strait.
-[[File:Map of the Arctic Region.png|center|thumb|675x675px|'''Map of the Arctic Region showing the Northern Sea Route and the Northwest Passage''']]
-== Poles ==
+=== Seasons Overview ===
+(See also, [[Time: Arctic|Time Variable]])
-The term “North Pole” is one sometimes used incorrectly. There are actually four poles in the Arctic: the North Pole, the North Magnetic Pole, the North Geomagnetic Pole, and the Northern Pole of Inaccessibility. A geomagnetic pole is an antipodal point where the axis of a best-fitting dipole intersects the surface of the Earth. This theoretical dipole is equivalent to a powerful bar magnet at the center of Earth and comes closer than any other model to accounting for the magnetic field observed at Earth's surface. In contrast, the magnetic poles of the Earth are not antipodal; that is, the line on which they lie does not pass through Earth's center. A pole of inaccessibility marks a location that is the most challenging to reach owing to its remoteness from geographical features that could provide access. Often it refers to the most distant point from coastlines.
+The midnight sun (also known as white nights or polar day) is a natural phenomenon that occurs in the summer months in places north of the Arctic Circle, when the sun remains visible at the local midnight.
+[[File:Daylight graph.png|alt=Daylight Graph|thumb|
+Small changes in latitude can drastically impact the amount of sunlight experienced in the Arctic region.
+]]
+Because of Earth?s axial tilt, the sun does not set at high latitudes in local summer. The midnight sun is visible at the Arctic Circle from 12 June until 1 July. At the pole itself, the sun rises and sets only once each year on the equinox. During summer, the sun continuously moves in circles around the observer, reaching its highest point in the sky at the summer solstice.
-The '''North Pole''' (also known as the Geographic North Pole or Terrestrial North Pole), is the point in the Northern Hemisphere where the Earth's axis of rotation meets its surface. The North Pole is the northernmost point on the Earth, lying diametrically opposite the South Pole. It defines geodetic latitude 90°North, as well as the direction of true north. At the North Pole all directions point south; all lines of longitude converge there, so its longitude can be defined as any degree value. Along tight latitude circles, counterclockwise is east and clockwise is west. The North Pole is at the center of the Northern Hemisphere. The sea depth at the North Pole has been measured at 4,261 m (13,980 ft) by the Donovian Mir submersible in 2007.
+=== Precipitation ===
+The Arctic has low precipitation caused by sinking air in the high-pressure belts and low temperatures. Snow or rain occur at times, but evaporation from the cold sea and land surfaces is slow, and the cold air has little capacity for moisture. Most precipitation in the Arctic comes in the form of snow. Snow particles constitute the clouds of cirrus type?namely cirrus, cirrostratus, and cirrocumulus?and many clouds of alto type. Ice and snow clouds originate normally only at temperatures below the freezing point; , snow particles ?can occur near the surface and may appear as ice fogs. If cold air near the ground is overlain by warmer air (a very common occurrence in polar regions, especially in winter), mixture at the border leads to super-saturation in the cold air. Small ice columns and needles, ?diamond dust,? will be formed and will float down, glittering, even from a cloudless sky.? The presence of ice crystals in the atmosphere can cause optical effects around light sources appearing as halos, arcs, circles, mock suns, and coronas. Sunshine reflection from snow will cause severe sunburn on all exposed skin and damage to retinas. Units must issue effective sunglasses to prevent snow blindness in troops and sunblock creams to prevent sunburn. When raindrops fall through a cold layer of air (, ) and become super-cooled, freezing rain occurs. The drops may freeze on impact with the ground to form a very slippery and dangerous "glazed" ice that is difficult to see because it is almost transparent.
-The '''North Magnetic Pole''' (also known as the Magnetic Dip Pole) is the wandering point on the surface of Earth's Northern Hemisphere at which the planet's magnetic field points vertically downwards (in other words, if a magnetic compass needle is allowed to rotate about a horizontal axis, it will point straight down). The North Magnetic Pole moves over time due to magnetic changes in the Earth's core. In 2001, it was determined by the Geological Survey of Canada to lie west of Ellesmere Island in northern Canada at 81.3°N 110.8°W. It was situated at 83.1°N 117.8°W in 2005. In 2009, while still situated within the Canadian Arctic territorial claim at 84.9°N 131.0°W, it was moving toward Donovia at between 55 and 60 kilometers (34 and 37 mi) per year. By 2017, the pole had moved beyond the Canadian Arctic territorial claim to 86.5°N 172.6°W.
+=== Wind ===
-[[File:Wandering Pole.png|center|frameless|'''Movement of the Magnetic North Pole''']]
+Wind speeds over the Arctic Basin and the western Canadian Archipelago average between four and six meters per second (14 and 22 kilometers per hour [km/h], nine and 13 miles per hour [mph]) in all seasons. Stronger winds do occur in storms, often causing whiteout conditions, but they rarely exceed 25 meters per second (90 km/h, 55 mph) in these areas.
-The '''North Geomagnetic Pole''' is the center of the 'open' magnetic field lines which connect to the interplanetary magnetic field and provide a direct route for the solar wind to reach the ionosphere. As of 2015, it was located at approximately 80.37°N 72.62°W, on Ellesmere Island, Nunavut, Canada. The locations of geomagnetic poles are predicted by the [https://www.ngdc.noaa.gov/IAGA/vmod/igrf.html International Geomagnetic Reference Field], a statistical fit to measurements of the Earth's field by satellites and in geomagnetic observatories.
-The '''Northern Pole of Inaccessibility''' (also known as the Arctic pole of inaccessibility and the Arctic pole) is located on the Arctic Ocean pack ice at a distance farthest from any land mass. It lies at 85°48′N 176°9′W, 1,008 km (626 mi) from the three closest landmasses: Ellesmere Island, Komsomolets Island, and Henrietta Island. Due to constant motion of the sea ice, no permanent structure can exist at this pole.
-== Sea Ice ==
-The cover of sea ice (above latitude 60°N) reflects most of incoming solar radiation and keeps the surface temperatures low. Wind and water keep the ice in constant motion causing cracks, open ponds, and pressure ridges. Pressure ridge can stack very high, and reach down in the water 10-25 m (33-80 ft). Sea ice in the Arctic Ocean generates cold water that drives the circulation of the world ocean system. The people's Republic of Olvana is using space assets to track sea ice worldwide. They also are using the Seawing 1000 underwater unmanned vehicle (UUV) to map the Arctic sea bed and measure ice thickness.
-The impact of global warming on Arctic Ocean sea ice is expected to continue. This graphic shows the U.S. Navy’s prediction of open water availability and the number ships passing through the Bering Strait, the Northern Sea Route (NSR) (4,740 nautical miles), the Northwest Passage (5,225 nautical miles), and the Transpolar Route (4,170 nautical miles), 2012-2030.
+During all seasons, the strongest average winds are found in the North Atlantic seas, Baffin Bay, Bering Sea, and Chukchi Sea, where cyclone activity is most common. On the Atlantic side, the winds are strongest in winter, averaging seven to 12 m/s (25 to 43 km/h, 16 to 27 mph), and weakest in summer, averaging five to seven m/s (18 to 25 km/h, 11 to 16 mph). Maximum wind speeds in the Atlantic region can approach 50 m/s (180 km/h, 110 mph) in winter. On the Pacific side they average six to nine m/s (22 to 32 km/h, 13 to 20 mph) year-round.
-[[File:Arctic Sea Route Navigability.png|center|thumb|520x520px|'''Arctic Sea Route Navigability''']]
-Much has been researched, written, and argued over concerning the extent of Arctic Ocean sea ice. These two graphics show some of the data. One is a graphic from the National Snow and Ice Data Center showing the Arctic Ocean sea ice extent for the months of September and March of each year from 1979 through 2016. September and March are when the minimum and maximum extent typically occur each year. The other shows the range of Arctic Ocean sea ice, 1979-2007 as observed by the National Aeronautics and Space Administration (NASA).
+=== Visibility ===
-[[File:Climate Change Indicators- Arctic Sea Ice, 1979-2016.png|center|thumb|459x459px|'''Climate Change Indicators- Arctic Sea Ice, 1979-2016''']]
+Extensive snow and ice pose challenges to imaging, as terrain variations can be difficult to discern.
-[[File:Sea Ice Concentration.png|center|thumb|461x461px|'''The Arctic as observed by the Advanced Microwave Scanning Radiometer for EOS (AMSR-E) aboard NASA’s Aqua satellite on September 16, 2007''']]
-== Icebergs ==
+=== Hazards ===
+Natural hazards include ice islands and icebergs in maritime areas, permafrost on land, and extreme temperatures. Permafrost is receding in all regions. This could potentially result in the reemergence of pathogens preserved in permafrost and facilitate the northward spread of current, geographically restricted pathogens.
-In the Arctic Ocean, the highest latitude sources of icebergs are Svalbard archipelago north of Norway and the islands of the Donovian Arctic. 26% come from Svalbard, 36% from Franz Josef Land, 32% from Novaya Zamlya, 6% from Severnaya Zemlya, and .3% from Ushakov Island. These primarily affect travel in the Barents or Kara Seas. In the Amerasia Basin, most Arctic icebergs originate from the Greenland ice sheet. Arctic icebergs tend to be smaller and more randomly shaped than Antarctic icebergs. Most icebergs are actually ice islands. Ice islands produced by Ellesmere Island calve into the Beaufort Gyre.
+==== Events ====
+Ice islands occasionally break away from northern Ellesmere Island; icebergs calved from glaciers in western Greenland and extreme northeastern Canada; permafrost in islands; virtually ice locked from October to June; ships subject to superstructure icing from October to May. Ice islands should be examined for depth and stability before placing landing zones or encampments on them.
-= '''Air and Space Domains''' =
+==== Disease ====
-Air transport in the Arctic is challenging at best. Weather changes, constant threat of fog, and lack of GPS force pilots to use multiple techniques to stay aloft and navigate.
+There are few if any significant localized disease phenomena in the Arctic. Personnel assigned to high latitudes are at higher risk of developing sleep and affective disorders that are deleterious to efficiency. These are associated with the extreme periods of daylight in summer and darkness in winter.
-== Navigation and Landing Challenges ==
+==== Flora ====
-Global Navigation Satellite System (GNSS) is the standard generic term for satellite navigation systems that provide autonomous geo-spatial positioning with global coverage. This term includes the GPS (U.S.), GLONASS (Donovia), Galileo (EU), BeiDou (Olvana) and other regional systems. GNSS is a term used worldwide. The curvature of the Earth north of 65°N negates the use of localizer performance with vertical guidance (LPV) for landings. LPV is an aviation instrument approach dependent on high-precision GPS. EGNOS Safety of Life Service (SoL) is limited past 70°N. GNSS is also susceptible being jammed, as happened in Arctic Norway in September 2017. This led to GNSS navigation being suspended.
+There are few toxic flora that are indigenous to the Arctic, although the Arctic poppy has a low toxicity level if ingested.
-== Solar Flares and Storms ==
+==== Fauna ====
-Solar flares are measured on a scale of intensity ranging from A, B, M, C to X. Similar to the Richter scale for earthquakes, each letter represents a 10-fold increase in energy output. So an X is ten times an M and 100 times a C. Within each letter class there is a finer scale from 1 to 9. When a solar flare occurs, radiation effects can be felt on Earth in as little as an hour with disruptions to communication technology. For more information on this effect, see the Information Variable.
+Black, brown, and polar bears are all native to the Arctic. Black bears will generally only attack if surprised or threatened. Brown bears and polar bears will hunt humans. Wolves and lynxes are unlikely to attack humans unless injured and/or isolated. Moose will attack if surprised or threatened and will defend their territory. Marine mammals including walruses and sea lions can be dangerous if surprised or threatened. Some insects survive north of the Arctic, particularly the low Arctic region, including flies and mosquitos that thrive in the high-humidity peat lands.
-{| class="wikitable"
-|+Solar Flare Classification<ref>https://www.nasa.gov/mission_pages/sunearth/news/X-class-flares.html</ref>
-|'''Solar Category'''
-|'''Remarks'''
-|-
-|A
-|Near background  level
-|-
-|B
-|10 times more  powerful than A class.
-|-
-|C
-|Too weak to  noticeably affect Earth.
-|-
-|M
-|Medium size  event. Can cause brief radio blackouts at the poles and minor radiation  storms that might endanger astronauts. Minor radiation storms sometimes  follow an M-class flare.
-|-
-|X
-|Ten times an M  and 100 times a C. X class flares can go higher than X-10. Can create long  lasting radiation storms that can harm satellites, communications systems,  and even ground-based technologies and power grids.
-|}
-<references />
 [[Category:DATE]]