Pinnipeds, commonly known as seals, are a widely distributed and diverse clade of carnivorous, fin-footed, semiaquatic marine mammals. They comprise the extant families Odobenidae and Phocidae, there are 33 extant species of pinnipeds, and more than 50 extinct species have been described from fossils. While seals were historically thought to have descended from two lines, molecular evidence supports them as a monophyletic lineage. Pinnipeds belong to the order Carnivora and their closest living relatives are bears and musteloids, Seals range in size from the 1 m and 45 kg Baikal seal to the 5 m and 3,200 kg southern elephant seal, which is the largest carnivoran. They have streamlined bodies and four limbs that are modified into flippers, though not as fast in the water as dolphins, seals are more flexible and agile. Otariids use their front limbs primarily to themselves through the water, while phocids. Otariids and walruses have hind limbs that can be pulled under the body, by comparison, terrestrial locomotion by phocids is more cumbersome.
Otariids have visible ears, while phocids and walruses lack these. Pinnipeds have well-developed senses—their eyesight and hearing are adapted for both air and water, and they have a tactile system in their whiskers or vibrissae. Some species are adapted for diving to great depths. They have a layer of fat, or blubber, under the skin to keep warm in the cold water, although pinnipeds are widespread, most species prefer the colder waters of the Northern and Southern Hemispheres. They spend most of their lives in the water, but come ashore to mate, give birth, molt or escape predators, like sharks. They feed largely on fish and marine invertebrates, but a few, like the seal, feed on large vertebrates, such as penguins. Walruses are specialized for feeding on bottom-dwelling mollusks, male pinnipeds typically mate with more than one female, although the degree of polygyny varies with the species. The males of land-breeding species tend to mate with a number of females than those of ice- or water-breeding species.
Male pinniped strategies for reproductive success vary between defending females, defending territories that attract females and performing ritual displays or lek mating, pups are typically born in the spring and summer months and females bear almost all the responsibility for raising them. Mothers of some species fast and nurse their young for a short period of time while others take foraging trips at sea between nursing bouts. Walruses are known to nurse their young while at sea, Seals produce a number of vocalizations, notably the barks of California sea lions, the gong-like calls of walruses and the complex songs of Weddell seals
Aerial photography is the taking of photographs of the ground from an elevated/direct-down position. Usually the camera is not supported by a ground-based structure, mounted cameras may be triggered remotely or automatically, hand-held photographs may be taken by a photographer. Aerial photography should not be confused with air-to-air photography, where one or more aircraft are used as chase planes that chase, Aerial photography was first practiced by the French photographer and balloonist Gaspard-Félix Tournachon, known as Nadar, in 1858 over Paris, France. However, the photographs he produced no longer exist and therefore the earliest surviving aerial photograph is titled Boston, as the Eagle, taken by James Wallace Black and Samuel Archer King on October 13,1860, it depicts Boston from a height of 630m. Kite aerial photography was pioneered by British meteorologist E. D. Archibald in 1882 and he used an explosive charge on a timer to take photographs from the air. Frenchman Arthur Batut began using kites for photography in 1888, Samuel Franklin Cody developed his advanced Man-lifter War Kite and succeeded in interesting the British War Office with its capabilities.
The first use of a motion picture camera mounted to an aircraft took place on April 24,1909 over Rome in the 3,28 silent film short. The use of aerial photography rapidly matured during the war, as aircraft were equipped with cameras to record enemy movements. At the start of the conflict, the usefulness of aerial photography was not fully appreciated, germany adopted the first aerial camera, a Görz, in 1913. The French began the war with several squadrons of Blériot observation aircraft equipped with cameras for reconnaissance, the French Army developed procedures for getting prints into the hands of field commanders in record time. Frederick Charles Victor Laws started aerial photography experiments in 1912 with No.1 Squadron of the Royal Flying Corps, in 1916 the Austro-Hungarian Monarchy made vertical camera axis aerial photos above Italy for map-making. The camera was inserted into the floor of the aircraft and could be triggered by the pilot at intervals. In January 1918, General Allenby used five Australian pilots from No.1 Squadron AFC to photograph a 624 square miles area in Palestine as an aid to correcting and improving maps of the Turkish front and this was a pioneering use of aerial photography as an aid for cartography.
Beginning 5 January, they flew with an escort to ward off enemy fighters. The first commercial aerial photography company in the UK was Aerofilms Ltd, founded by World War I veterans Francis Wills, the company soon expanded into a business with major contracts in Africa and Asia as well as in the UK. Operations began from the Stag Lane Aerodrome at Edgware, using the aircraft of the London Flying School, the Aircraft Manufacturing Company, hired an Airco DH.9 along with pilot entrepreneur Alan Cobham. From 1921, Aerofilms carried out vertical photography for survey and mapping purposes, during the 1930s, the company pioneered the science of photogrammetry, with the Ordnance Survey amongst the companys clients. One Fairchild aerial survey aircraft in 1935 carried unit that combined two synchronized cameras, and each camera having five six inch lenses with a ten-inch lenses, each photo covered two hundred and twenty five square miles
A shield volcano is a type of volcano usually built almost entirely of fluid lava flows. They are named for their low profile, resembling a warriors shield lying on the ground and this is caused by the highly fluid lava they erupt, which travels farther than lava erupted from stratovolcanoes. This results in the accumulation of broad sheets of lava. The shape of shield volcanoes is due to the low viscosity of their mafic lava, Shield volcanoes are built by effusive eruptions, which flow out in all directions to create a shield like that of a warrior. Shield volcano itself is taken from the German term Schildvulkan, examples of pyroclastic shields include Billy Mitchell volcano in Papua New Guinea and the Purico Complex in Chile, an example of a felsic shield is the Big Obsidian Flow in Oregon. Active shield volcanoes experience near-continuous eruptive activity over long periods of time. Mount Everest, by comparison, is 8,848 m in height, the research has not yet been confirmed. Shield volcanoes feature a slope that gradually steepens with elevation before eventually flattening near the summit.
In height they are typically about one twentieth their width, although the general form of a typical shield volcano varies little worldwide regional differences exist in their size and morphological characteristics. 4° and an average volume of 1.7 km3. Rift zones are a prevalent feature on shield volcanoes that is rare on other volcanic types, the large, decentralized shape of Hawaiian volcanoes as compared to their smaller, symmetrical Icelandic cousins can be attributed to rift eruptions. Fissure venting is common in Hawaiʻi, most Hawaiian eruptions begin with a wall of fire along a major fissure line before centralizing to a small number of points. These eruptions, the calmest of volcanic events, are characterized by the emission of highly fluid basaltic lavas with low gaseous content. These lavas travel a far greater distance than those of other types before solidifying, forming extremely wide. Low volumes of such lavas layered over long periods of time are what slowly constructs the characteristically low, central-vent eruptions, often take the form of large lava fountains, which can reach heights of hundreds of meters or more.
If eruptive rates are enough, they may even form splatter-fed lava flows. Hawaiian eruptions are often extremely long lived, Puʻu ʻŌʻō, a cone of Kilauea, has been erupting continuously since 1983. These lava flows can be anywhere between 2 and 20 m thick, pāhoehoe flows, in contrast, move in more conventional sheets, or by the advancement of lava toes in snaking lava columns. Increasing viscosity on the part of the lava or shear stress on the part of local topography can morph a pāhoehoe flow into an aa one, although most shield volcanoes are by volume almost entirely Hawaiian and basaltic in origin, they are rarely exclusively so
An island or isle is any piece of sub-continental land that is surrounded by water. Very small islands such as emergent land features on atolls can be called islets, skerries, an island in a river or a lake island may be called an eyot or ait, and a small island off the coast may be called a holm. A grouping of geographically or geologically related islands is called an archipelago, an island may be described as such, despite the presence of an artificial land bridge. Example and its causeway, or the various Dutch delta islands, there are two main types of islands in the sea and oceanic. The word island derives from Middle English iland, from Old English igland, Old English ieg is actually a cognate of Swedish ö and German Aue, and related to Latin aqua. There is a difference between islands and continents in terms of geology, continents sit on continental lithosphere which is part of tectonic plates floating high on Earths mantle. Oceanic crust is part of tectonic plates, but it is denser than continental lithosphere, Islands are either extensions of the oceanic crust or geologically they are part of some continent sitting on continental lithosphere.
This holds true for Australia, which sits on its own continental lithosphere, continental islands are bodies of land that lie on the continental shelf of a continent. A special type of island is the microcontinental island, which is created when a continent is rifted. Examples are Madagascar and Socotra off Africa, the Kerguelen Islands, New Caledonia, New Zealand, another subtype is an island or bar formed by deposition of tiny rocks where water current loses some of its carrying capacity. While some are transitory and may disappear if the volume or speed of the current changes, others are stable, oceanic islands are islands that do not sit on continental shelves. The vast majority are volcanic in origin, such as Saint Helena in the South Atlantic Ocean, the few oceanic islands that are not volcanic are tectonic in origin and arise where plate movements have lifted up the ocean floor above the surface. Examples are Saint Peter and Paul Rocks in the Atlantic Ocean, one type of volcanic oceanic island is found in a volcanic island arc.
These islands arise from volcanoes where the subduction of one plate under another is occurring, examples are the Aleutian Islands, the Mariana Islands, and most of Tonga in the Pacific Ocean. The only examples in the Atlantic Ocean are some of the Lesser Antilles, another type of volcanic oceanic island occurs where an oceanic rift reaches the surface. There are two examples, which is the second largest volcanic island, and Jan Mayen. A third type of oceanic island is formed over volcanic hotspots. A hotspot is more or less stationary relative to the tectonic plate above it
Vertebrates /ˈvɜːrtᵻbrᵻts/ comprise all species of animals within the subphylum Vertebrata /-ɑː/. Vertebrates represent the majority of the phylum Chordata, with currently about 66,000 species described. Vertebrates include the fish and the jawed vertebrates, which include the cartilaginous fish. A bony fish known as the lobe-finned fishes is included with tetrapods, which are further divided into amphibians, mammals. Extant vertebrates range in size from the frog species Paedophryne amauensis, at as little as 7.7 mm, to the blue whale, vertebrates make up less than five percent of all described animal species, the rest are invertebrates, which lack vertebral columns. The vertebrates traditionally include the hagfish, which do not have proper vertebrae due to their loss in evolution, though their closest living relatives, hagfish do, possess a cranium. For this reason, the vertebrate subphylum is sometimes referred to as Craniata when discussing morphology, molecular analysis since 1992 has suggested that hagfish are most closely related to lampreys, and so are vertebrates in a monophyletic sense.
Others consider them a group of vertebrates in the common taxon of craniata. The word origin of vertebrate derives from the Latin word vertebratus, the Proto-Indo-European language origins are still unclear. Vertebrate is derived from the vertebra, which refers to any of the bones or segments of the spinal column. All vertebrates are built along the basic body plan, a stiff rod running through the length of the animal, with a hollow tube of nervous tissue above it. In all vertebrates, the mouth is found at, or right below, the remaining part of the body continuing after the anus forms a tail with vertebrae and spinal cord, but no gut. However, a few vertebrates have secondarily lost this anatomy, retaining the notochord into adulthood, such as the sturgeon, jawed vertebrates are typified by paired appendages, but this trait is not required in order for an animal to be a vertebrate. All basal vertebrates breathe with gills, the gills are carried right behind the head, bordering the posterior margins of a series of openings from the pharynx to the exterior.
Each gill is supported by a cartilagenous or bony gill arch, the bony fish have three pairs of arches, cartilaginous fish have five to seven pairs, while the primitive jawless fish have seven. The vertebrate ancestor no doubt had more arches than this, as some of their relatives have more than 50 pairs of gills. In amphibians and some primitive fishes, the larvae bear external gills. These are reduced in adulthood, their function taken over by the gills proper in fishes, some amphibians retain the external larval gills in adulthood, the complex internal gill system as seen in fish apparently being irrevocably lost very early in the evolution of tetrapods
Queen Maud Land
Queen Maud Land is a c.2.7 million-square-kilometre region of Antarctica claimed as a dependent territory by Norway. The territory lies between 20° west and 45° east, between the British Antarctic Territory to the west and the Australian Antarctic Territory to the east. On most maps there had been an area between Queen Maud Lands borders of 1939 and the South Pole until June 12,2015 when Norway formally annexed that area. Positioned in East Antarctica, the territory comprises about one-fifth of the area of Antarctica. The claim is named after the Norwegian queen Maud of Wales, Norwegian Hjalmar Riiser-Larsen was the first person known to have set foot in the territory, in 1930. On 14 January 1939, the territory was claimed by Norway, from 1939 until 1945, Nazi Germany claimed New Swabia, which consisted of part of Queen Maud Land. On 23 June 1961, Queen Maud Land became part of the Antarctic Treaty System and it is one of two Antarctic claims made by Norway, the other being Peter I Island. They are administrated by the Polar Affairs Department of the Norwegian Ministry of Justice, most of the territory is covered by the Antarctic ice sheet, and a tall ice wall stretches throughout its coast.
In some areas further within the ice sheet, mountain ranges breach through the ice, allowing for birds to breed, the region is divided into the Princess Martha Coast, Princess Astrid Coast, Princess Ragnhild Coast, Prince Harald Coast and Prince Olav Coast. The waters off the coast are called the King Haakon VII Sea, there is no permanent population, although there are 12 active research stations housing a maximum average of 40 scientists, the numbers fluctuating depending on the season. Six are occupied year-round, while the remainder are seasonal summer stations, the territory is estimated to cover around 2,700,000 square kilometres. The limits of the claim, put forth in 1939, did not fix the northern and southern limits other than as the beach in Antarctica. With the land lies beyond this beach and the sea beyond. The sea that extends off the coast between the limits of Queen Maud Land is generally called King Haakon VII Sea. There is no land at the coast, the coast consists of a 20-to-30-metre high wall of ice throughout almost the entire territory.
It is thus possible to disembark from a ship in a few places. The other major mountain ranges are the Heimefront Range, Orvin Mountains, Wohlthat Mountains, the ground of Queen Maud Land is dominated by Precambrian gneiss, formed c.1 to 1.2 Ga, before the creation of the supercontinent Gondwana. The mountains consist mostly of crystalline and granitic rocks, formed c.500 to 600 Ma in the Pan-African orogeny during the assembly of Gondwana, in the farthest western parts of the territory, there are younger sedimentary and volcanic rocks
The Holocene is the geological epoch that began after the Pleistocene at approximately 11,700 years before present. The term Recent has often used as an exact synonym of Holocene. The Holocene is part of the Quaternary period and its name comes from the Ancient Greek words ὅλος and καινός, meaning entirely recent. It has been identified with the current warm period, known as MIS1, given these, a new term, Anthropocene, is specifically proposed and used informally only for the very latest part of modern history involving significant human impact. It is accepted by the International Commission on Stratigraphy that the Holocene started approximately 11,700 years ago, the epoch follows the Pleistocene and the last glacial period. The Holocene can be subdivided into five time intervals, or chronozones, based on climatic fluctuations, Boreal, Atlantic and they find a general correspondence across Eurasia and North America, though the method was once thought to be of no interest. The scheme was defined for Northern Europe, but the changes were claimed to occur more widely.
The periods of the include a few of the final pre-Holocene oscillations of the last glacial period. Paleontologists have not defined any faunal stages for the Holocene, if subdivision is necessary, periods of human technological development, such as the Mesolithic and Bronze Age, are usually used. However, the time periods referenced by these terms vary with the emergence of those technologies in different parts of the world, the Holocene may be divided evenly into the Hypsithermal and Neoglacial periods, the boundary coincides with the start of the Bronze Age in Europe. According to some scholars, a division, the Anthropocene, has now begun. Continental motions due to plate tectonics are less than a kilometre over a span of only 10,000 years, ice melt caused world sea levels to rise about 35 m in the early part of the Holocene. The sea level rise and temporary land depression allowed temporary marine incursions into areas that are now far from the sea, Holocene marine fossils are known, for example, from Vermont and Michigan.
Other than higher-latitude temporary marine incursions associated with depression, Holocene fossils are found primarily in lakebed, floodplain. Holocene marine deposits along low-latitude coastlines are rare because the rise in sea levels during the period exceeds any likely tectonic uplift of non-glacial origin, post-glacial rebound in the Scandinavia region resulted in the formation of the Baltic Sea. The region continues to rise, still causing weak earthquakes across Northern Europe, the equivalent event in North America was the rebound of Hudson Bay, as it shrank from its larger, immediate post-glacial Tyrrell Sea phase, to near its present boundaries. Climate has been stable over the Holocene. It appears that this was influenced by the glacial ice remaining in the Northern Hemisphere until the date
Drift ice is any sea ice other than fast ice, the latter being attached to the shoreline or other fixed objects. Drift ice is carried along by winds and sea currents, hence its name, when drift ice is driven together into a large single mass, it is called pack ice. Wind and currents can pile up that ice to form ridges up to several metres in height and these represent a challenge for icebreakers and offshore structures operating in cold oceans and seas. Drift ice consists of floes, individual pieces of sea ice 20 metres or more across. Seasonal ice drift in the Sea of Okhotsk by the northern coast of Hokkaidō, Japan has become a tourist attraction of this area with harsh climate, the Sea of Okhotsk is the southernmost area in the Northern hemisphere where drift ice may be observed. Drift ice affects, Security of navigation Climatic impact Geological impact Biosphere influence The two major ice packs are the Arctic ice pack and the Antarctic ice pack, polar packs significantly change their size during seasonal changes of the year.
Because of vast amounts of water added to or removed from the oceans and atmosphere, the behavior of polar ice packs has a significant impact on global changes in climate
The Antarctic is a polar region, specifically the region around the Earths South Pole, opposite the Arctic region around the North Pole. The Antarctic comprises in the sense the continent of Antarctica. The region covers some 20% of the Southern Hemisphere, of which 5. 5% is the area of the Antarctic continent itself. All of the land and ice shelves south of 60°S latitude are administrated under the Antarctic Treaty System, in a biogeographic sense, the Antarctic ecozone is one of eight ecozones of the Earths land surface. Most of the Antarctic region is situated south of 60°S latitude parallel, there are only two species of flowering plant, Antarctic hair grass and Antarctic pearlwort, but a range of mosses, liverworts and macrofungi. The first Antarctic land discovered was the island of South Georgia, the first human born in the Antarctic was Solveig Gunbjørg Jacobsen born on 8 October 1913 in Grytviken, South Georgia. However, the region is visited by more than 40,000 tourists annually, the definitive results of the conference was presented at the Antarctic Treaty states meeting in Uruguay in May 2010.
The Antarctic hosts the worlds largest protected area comprising 1.07 million km2, the South Georgia, because Antarctica surrounds the South Pole, it is theoretically located in all time zones. For practical purposes, time zones are based on territorial claims or the time zone of a stations owner country or supply base. Antarctic Circle History of Antarctica Krupnik, Michael A. Lang, smithsonian at the Poles, Contributions to International Polar Year Science
The Antarctic Peter I Island and the sub-Antarctic Bouvet Island are dependent territories and thus not considered part of the Kingdom. Norway lays claim to a section of Antarctica known as Queen Maud Land, until 1814, the kingdom included the Faroe Islands and Iceland. It included Isle of Man until 1266, Shetland and Orkney until 1468, Norway has a total area of 385,252 square kilometres and a population of 5,258,317. The country shares a long border with Sweden. Norway is bordered by Finland and Russia to the north-east, Norway has an extensive coastline, facing the North Atlantic Ocean and the Barents Sea. King Harald V of the Dano-German House of Glücksburg is the current King of Norway, erna Solberg became Prime Minister in 2013, replacing Jens Stoltenberg. A constitutional monarchy, Norway divides state power between the Parliament, the Cabinet and the Supreme Court, as determined by the 1814 Constitution, the kingdom is established as a merger of several petty kingdoms. By the traditional count from the year 872, the kingdom has existed continuously for 1,144 years, Norway has both administrative and political subdivisions on two levels and municipalities.
The Sámi people have an amount of self-determination and influence over traditional territories through the Sámi Parliament. Norway maintains close ties with the European Union and the United States, the country maintains a combination of market economy and a Nordic welfare model with universal health care and a comprehensive social security system. Norway has extensive reserves of petroleum, natural gas, lumber, the petroleum industry accounts for around a quarter of the countrys gross domestic product. On a per-capita basis, Norway is the worlds largest producer of oil, the country has the fourth-highest per capita income in the world on the World Bank and IMF lists. On the CIAs GDP per capita list which includes territories and some regions, from 2001 to 2006, and again from 2009 to 2017, Norway had the highest Human Development Index ranking in the world. It has the highest inequality-adjusted ranking, Norway ranks first on the World Happiness Report, the OECD Better Life Index, the Index of Public Integrity and the Democracy Index.
Norway has two names, Noreg in Nynorsk and Norge in Bokmål. The name Norway comes from the Old English word Norðrveg mentioned in 880, meaning way or way leading to the north. In contrasting with suðrvegar southern way for Germany, and austrvegr eastern way for the Baltic, the Anglo-Saxon of Britain referred to the kingdom of Norway in 880 as Norðmanna land. This was the area of Harald Fairhair, the first king of Norway, and because of him
A glacier terminus, toe, or snout, is the end of a glacier at any given point in time. Although glaciers seem motionless to the observer, in reality glaciers are in endless motion, the position of a glacier terminus is impacted by localized or regional temperature change over time. Tracking the change in location of a terminus is a method of monitoring a glaciers movement. The end of the terminus is measured from a fixed position in neighboring bedrock periodically over time. The difference in location of a terminus as measured from this fixed position at different time intervals provides a record of the glaciers change. A similar way of tracking glacier change is comparing photographs of the position at different times. The form of a terminus is determined by many factors. If the glacier is retreating, it is usually mildly sloping in form because a melting glacier tends to assume this shape. The photograph above shows the glacial lakes formed by the glacial termini on the surface of the debris-covered glaciers over the last several decades in the Bhutan-Himalaya region