Río Negro Province
Río Negro is a province of Argentina, located at the northern edge of Patagonia. Neighboring provinces are from the south clockwise Chubut, Neuquén, Mendoza, La Pampa and Buenos Aires. To the east lies the Atlantic Ocean, its capital is Viedma. Other important cities include the ski resort town of General Roca and Cipolletti. Ferdinand Magellan was the first European explorer to visit the coasts of the provinces in 1520. Italian priest Nicolás Mascardi founded the Jesuit mission Nuestra Senora de Nahuel Huapi in 1670 at the shore of the Nahuel Huapi Lake, at the feet of the Andes range. Part of the Argentine territory called Patagonia, in 1884 it was organised into the Territorio Nacional del Río Negro and General Lorenzo Vintter was appointed as the territory's first governor, it was only in 1957. Río Negro is one of the six provinces, it is bounded to the north by the Colorado River which separates it from La Pampa Province, to the east by the Atlantic Ocean and to the west by the Andes and the Limay River.
The 42nd parallel south marks the southern limit of the province. With an area of 203,013 square kilometres, it is the 4th largest province by area; the climate of the province is temperate at low elevations, cold in the higher Andean peaks. The mean annual temperatures in the province are cold for its latitude owing to the marine currents to the east and higher altitude to the west. Mean annual temperatures in the province can vary, depending on distance from the sea; the northern parts of the province are the warmest, with a mean annual temperature of more than 15 °C while the coldest areas are found in the Cordillera where the mean annual temperatures are less than 10 °C. At the highest peaks, the mean annual temperature is less than freezing. Summer temperatures can exceed 40 °C although the mean January temperatures range from 20 to 24 °C. In contrast, the Andean region has milder summers with mean January temperatures of 15 °C or less, depending on the altitude. In July, mean temperatures range from 7 to 8 °C on the coast in the north to around 2 to 3 °C in the central plateau.
Relative humidity is lower in the central plateau where they average 50%. Along the coastal regions, humidity is higher with a mean annual humidity of 60% while the Andean region has the highest humidity with an average annual humidity exceeding 65% due to the lower temperatures there. In all locations, humidity is lower in the summer and higher in the winter owing to the higher temperatures in the summer; the Andes block most of the moisture from the Pacific Ocean from coming in, causing it to release most of the precipitation on its western slopes and as such, most of the province is dry, with a mean annual precipitation around 200 millimetres. Coastal areas and northern parts of the province receive a higher precipitation, where it can average above 300 millimetres a year; the Andean region receives the most precipitation with areas receiving a mean annual precipitation of 200 to 1,000 millimetres in which the precipitation gradient is strong and increases westwards. In some places, precipitation can exceed 3,000 millimetres a year.
Most of the Andean region has a rainfall pattern, Mediterranean like, similar to Central Chile in which most of the precipitation falls during the winter months and summers are dry. One dominant characteristic of the climate is the strong winds that are observed throughout the province. Summers tend to be windier than winters. Winds coming from the west and northwest are common, occurring 50% of the time. There is some tendency for the winds to come from the east on the coastal regions when sea breezes from the east can occur when westerly winds are weak, which can be felt up to 10 kilometres from the coast; the mean wind speed throughout the province varies with the northern parts having the lowest wind speeds while the highest altitude areas being the windiest. Except for the northern parts of the province, mean annual wind speeds exceed 4 metres per second. Cloud cover varies throughout the province, ranging from more than 60% in the Andean region to about 40% in the coastal areas; the central plateaus have intermediate amounts of cloud cover between these 2 regions.
As such, the Andean region is cloudier than the rest of the province. Sunshine ranges from 10–11 hours of sunshine/day in January to about 5 hours of sunshine/day to less than 3 hours of sunshine/day in July. According to the results from the 2010 census, the province has a population of 638,645 with 316,774 males and 321,871 females, it constitutes 1.6% of the total population in Argentina. This represented a 15.5% increase in the population compared to 2001 census which had 552,822 inhabitants. Amongst of all the provinces in Patagonia, it is the most populous, containing 30.4% of the total population in Patagonia. The province is home to four indigenous groups: The Tehuelches, the Puelches, the Pehuenches, the Mapuches. All of the indigenous population in the province are the Mapuches with the rest being small in number where their few descendants live in the neighbouring provinces; the Mapuches along with some of the Pehuenches lived in the western parts of the province although today, they live in the southern
Squid are cephalopods in the superorder Decapodiformes with elongated bodies, large eyes, eight arms and two tentacles. Like all other cephalopods, squid have a distinct head, bilateral symmetry, a mantle, they are soft-bodied, like octopuses, but have a small internal skeleton in the form of a rod-like gladius or pen, made of chitin. Squid diverged from other cephalopods during the Jurassic and occupy a similar role to teleost fish as open water predators of similar size and behaviour, they play an important role in the open water food web. The two long tentacles are used to grab the eight arms to hold and control it; the beak cuts the food into suitable size chunks for swallowing. Squid are rapid swimmers, moving by jet propulsion, locate their prey by sight, they are among the most intelligent of invertebrates, with groups of Humboldt squid having been observed hunting cooperatively. They are preyed on by sharks, other fish, sea birds and cetaceans sperm whales. Squid can change colour for signalling.
Some species are bioluminescent, using their light for counter-illumination camouflage, while many species can eject a cloud of ink to distract predators. Squid are used for human consumption with commercial fisheries in Japan, the Mediterranean, the southwestern Atlantic, the eastern Pacific and elsewhere, they are used in cuisines around the world known as "calamari". Squid have featured in literature since classical times in tales of giant squid and sea monsters. Squid are members of the class Cephalopoda, subclass Coleoidea; the squid orders Myopsida and Oegopsida are in the superorder Decapodiformes. Two other orders of decapodiform cephalopods are called squid, although they are taxonomically distinct from squids and differ recognizably in their gross anatomical features, they are the bobtail squid of order Sepiolida and the ram's horn squid of the monotypic order Spirulida. The vampire squid, however, is more related to the octopuses than to any squid; the cladogram, not resolved, is based on Sanchez et al, 2018.
Their molecular phylogeny used nuclear DNA marker sequences. If it is accepted that Sepiidae cuttlefish are a kind of squid the squids, excluding the vampire squid, form a clade as illustrated. Orders are shown in boldface. Crown coleoids diverged in the Permian. Squid diverged during the Jurassic. Both the coleoids and the teleost fish were involved in much adaptive radiation at this time, the two modern groups resemble each other in size, habitat and behaviour, however some fish moved into fresh water while the coleoids remained in marine environments; the ancestral coleoid was nautiloid-like with a strait septate shell that became immersed in the mantle and was used for buoyancy control. Four lines diverged from this, the cuttlefishes, the squids and the octopuses. Squid have differentiated from the ancestral mollusc such that the body plan has been condensed antero-posteriorly and extended dorso-ventrally. What may have been the foot of the ancestor is modified into a complex set of appendages around the mouth.
The sense organs are developed and include advanced eyes similar to those of vertebrates. The ancestral shell has been lost, with pen, remaining; the pen, made of a chitin-like material, is a feather-shaped internal structure that supports the squid's mantle and serves as a site for muscle attachment. The cuttlebone or sepion of the Sepiidae is calcareous and appears to have evolved afresh in the Tertiary. Squid are soft-bodied molluscs whose forms have been modified to adopt an active predatory lifestyle; the head and foot of the squid are at one end of a long body, this end is functionally anterior, leading the animal as it moves through the water. The foot has been transformed into a set of eight arms and two distinctive tentacles, which surround the mouth; the suckers may be stalked. Their rims may contain minute toothlike denticles; these features, as well as strong musculature, a small ganglion beneath each sucker to allow individual control, provide a powerful adhesion to grip prey. Hooks are present on the arms and tentacles in some species.
The two tentacles are retractile. Suckers are limited to the spatulate tip of the tentacle, known as the manus. In the mature male, the outer half of one of the left arms is hectocotylised – and ends in a copulatory pad rather than suckers; this is used for depositing a spermatophore inside the mantle cavity of a female. A ventral part of the foot has been converted into a funnel through which water exits the mantle cavity; the main body mass is enclosed in the mantle. These fins are not the main source of locomotion in most species; the mantle wall is muscled and internal. The visceral mass, covered by a thin, membranous epidermis, forms a cone-shaped posterior region known as the "visceral hump"; the mollusc shell is reduced to an internal, longitudinal chitinous "pen" in the functionally dorsal part of the animal. On the functionally ventral part of the body is an opening to the m
International Standard Book Number
The International Standard Book Number is a numeric commercial book identifier, intended to be unique. Publishers purchase ISBNs from an affiliate of the International ISBN Agency. An ISBN is assigned to each variation of a book. For example, an e-book, a paperback and a hardcover edition of the same book would each have a different ISBN; the ISBN is 13 digits long if assigned on or after 1 January 2007, 10 digits long if assigned before 2007. The method of assigning an ISBN is nation-based and varies from country to country depending on how large the publishing industry is within a country; the initial ISBN identification format was devised in 1967, based upon the 9-digit Standard Book Numbering created in 1966. The 10-digit ISBN format was developed by the International Organization for Standardization and was published in 1970 as international standard ISO 2108. Published books sometimes appear without an ISBN; the International ISBN agency sometimes assigns such books ISBNs on its own initiative.
Another identifier, the International Standard Serial Number, identifies periodical publications such as magazines and newspapers. The International Standard Music Number covers musical scores; the Standard Book Numbering code is a 9-digit commercial book identifier system created by Gordon Foster, Emeritus Professor of Statistics at Trinity College, for the booksellers and stationers WHSmith and others in 1965. The ISBN identification format was conceived in 1967 in the United Kingdom by David Whitaker and in 1968 in the United States by Emery Koltay; the 10-digit ISBN format was developed by the International Organization for Standardization and was published in 1970 as international standard ISO 2108. The United Kingdom continued to use the 9-digit SBN code until 1974. ISO has appointed the International ISBN Agency as the registration authority for ISBN worldwide and the ISBN Standard is developed under the control of ISO Technical Committee 46/Subcommittee 9 TC 46/SC 9; the ISO on-line facility only refers back to 1978.
An SBN may be converted to an ISBN by prefixing the digit "0". For example, the second edition of Mr. J. G. Reeder Returns, published by Hodder in 1965, has "SBN 340 01381 8" – 340 indicating the publisher, 01381 their serial number, 8 being the check digit; this can be converted to ISBN 0-340-01381-8. Since 1 January 2007, ISBNs have contained 13 digits, a format, compatible with "Bookland" European Article Number EAN-13s. An ISBN is assigned to each variation of a book. For example, an ebook, a paperback, a hardcover edition of the same book would each have a different ISBN; the ISBN is 13 digits long if assigned on or after 1 January 2007, 10 digits long if assigned before 2007. An International Standard Book Number consists of 4 parts or 5 parts: for a 13-digit ISBN, a prefix element – a GS1 prefix: so far 978 or 979 have been made available by GS1, the registration group element, the registrant element, the publication element, a checksum character or check digit. A 13-digit ISBN can be separated into its parts, when this is done it is customary to separate the parts with hyphens or spaces.
Separating the parts of a 10-digit ISBN is done with either hyphens or spaces. Figuring out how to separate a given ISBN is complicated, because most of the parts do not use a fixed number of digits. ISBN is most used among others special identifiers to describe references in Wikipedia and can help to find the same sources with different description in various language versions. ISBN issuance is country-specific, in that ISBNs are issued by the ISBN registration agency, responsible for that country or territory regardless of the publication language; the ranges of ISBNs assigned to any particular country are based on the publishing profile of the country concerned, so the ranges will vary depending on the number of books and the number and size of publishers that are active. Some ISBN registration agencies are based in national libraries or within ministries of culture and thus may receive direct funding from government to support their services. In other cases, the ISBN registration service is provided by organisations such as bibliographic data providers that are not government funded.
A full directory of ISBN agencies is available on the International ISBN Agency website. Partial listing: Australia: the commercial library services agency Thorpe-Bowker.
A sand wave is a lower regime sedimentary structure that forms across from tidal currents. Fossilized sand waves are known as ripple marks. Sand waves are formed through the action of the water. Sand waves are underwater. Sand dune Media related to Sand waves at Wikimedia Commons
Right whales or black whales are three species of large baleen whales of the genus Eubalaena: the North Atlantic right whale, the North Pacific right whale and the Southern right whale. They are classified in the family Balaenidae with the bowhead whale. Right whales have rotund bodies with arching rostrums, V-shaped blowholes and dark gray or black skin; the most distinguishing feature of a right whale is the rough patches of skin on its head, which appear white due to parasitism by whale lice. Right whales can grow up to more than 18 m long with a highest-recorded length of 19.8 m. Right whales are robust whales, weighing 100 short tons or more; the largest known right whales can attain 20.7 m in length and weigh up to 135,000 kg or 21.3 m with uncertainty, Their immense bulk makes right whale heavier than other whales of similar or greater length such as the humpback, gray and fin whales. In fact, right whales rank only behind the blue whale in sheer body mass. One explanation for their name is that whalers identified them as the "right" whale to kill on a hunt due to the plentiful oil and baleen they could provide.
All three species are migratory, moving seasonally to give birth. The warm equatorial waters form a barrier that isolates the northern and southern species from one another although the southern species, at least, has been known to cross the equator. In the Northern Hemisphere, right whales tend to avoid open waters and stay close to peninsulas and bays and on continental shelves, as these areas offer greater shelter and an abundance of their preferred foods. In the Southern Hemisphere, right whales feed far offshore in summer, but a large portion of the population occur in near-shore waters in winter. Right whales feed on copepods but consume krill and pteropods, they may forage the surface, underwater or the ocean bottom. During courtship, males gather into large groups to compete for a single female, suggesting that sperm competition is an important factor in mating behavior. Although the blue whale is the largest animal on the planet, the testes of the right whale are ten times larger than those of the blue whale – with each weighing up to 525 kilograms, they are by far the largest of any animal on Earth.
Gestation tends to last a year, calves are born at 1 short ton in weight and 4–6 m in length. Weaning occurs after eight months. Right whales were a preferred target for whalers because of their docile nature, their slow surface-skimming feeding behaviors, their tendency to stay close to the coast, their high blubber content. Today, the North Atlantic and North Pacific right whales are among the most endangered whales in the world, both species are protected in the United States by the Endangered Species Act; the western populations of both are endangered, with their total populations numbering in the hundreds. The eastern North Pacific population, on the other hand, with fewer than 50 individuals remaining, is critically endangered – further still, the eastern North Atlantic population, which numbers in the low teens at best, may be functionally extinct. Although the whales no longer face a threat from whaling, mankind remains by far the greatest threat to these species: the two leading causes of death are being struck by ships and entanglement in fishing gear.
For the North Atlantic right whale, for example, whose population was estimated at 411 in 2018, down from 451 in 2016 and 458 in 2015, these two anthropogenic factors alone account for 48% of all known right whale deaths since 1970. More than 85% of right whales have been entangled at least once. In 2017, at least 118 right whales were in the Gulf of St Lawrence, or a quarter of the local population, which fed in summer and fall months in the Bay of Fundy and Roadway basin; the habitat shift moved this population away from existing conservation efforts and into the path of busy shipping lanes and snow crab fisheries where Fisheries and Oceans Canada doubled the quotas in 2017. A popular explanation for the name right whales is that they were the right ones to hunt, as they float when killed and swim within sight of shore, they do not tend to shy away from approaching boats. As such, they were hunted nearly to extinction during the active years of the whaling industry; this origin is apocryphal.
In his history of American whaling, Eric Jay Dolin writes: Despite this plausible rationale, nobody knows how the right whale got its name. The earliest references to the right whale offer no indication why it was called that, some who have studied the issue point out that the word "right" in this context might just as be intended "to connote'true' or'proper,' meaning typical of the group." The right whales were first classified in the genus Balaena in 1758 by Carl Linnaeus, who at the time considered all of the right whales as a single species. Through the 1800s and 1900s, in fact, the family Balaenidae has been the subject of great taxonometric debate. Authorities have recategorized the three populations of right whale plus the bowhead whale, as one, three or four species, either in a single genus or in two separate genera. In the early whaling days, they were all thought to be a single species, Balaena mysticetus, it was recognized that bowheads and right whales were in fact different, John Edward Gray proposed the genus Eubalaena for the right whale in 1864.
Morphological factors such as differences in the skull shape
Deglaciation describes the transition from full glacial conditions during ice ages, to warm interglacials, characterized by global warming and sea level rise due to change in continental ice volume. Thus, it refers to the retreat of a glacier, an ice sheet or frozen surface layer, the resulting exposure of the Earth's surface; the decline of the cryosphere due to ablation can occur on any scale from global to localized to a particular glacier. After the Last Glacial Maximum, the last deglaciation begun, which lasted until the early Holocene. Around much of Earth, deglaciation during the last 100 years has been accelerating as a result of climate change brought on by anthropogenic changes to greenhouse gases; the previous deglaciation took place between 22ka until 11.5ka. This occurred when there was an annual mean atmospheric temperature on the earth that increased by 5 °C, accompanied by regional high-latitude warming that exceeded 10 °C; this was followed by noteworthy deep-sea and tropical-sea warming, between about 1-2 °C and 2-4 °C.
Not only did this warming occur, but the global hydrological budget experienced noticeable changes and regional precipitation patterns changed. As a result of all of this, the world's main ice sheets, including the ones located in Eurasia, North America and parts of the Antarctic melted; as a consequence, sea levels rose 120 metres. These processes did not occur and they did not occur at the same time; the process of deglaciation reflects a lack of balance between existing glacial extent and climatic conditions. As a result of net negative mass balance over time and ice sheets retreat; the repeated periods of increased and decreased extent of the global cryposhere reflect the cyclical nature of global and regional glaciology measured by ice ages and smaller periods known as glacials and interglacials. Since the end of the Last glacial period about 12,000 years ago, ice sheets have retreated on a global scale, Earth has been experiencing a warm interglacial period marked by only high-altitude alpine glaciers at most latitudes with larger ice sheet and sea ice at the poles.
However, since the onset of the Industrial Revolution, human activity has contributed to a rapid increase in the speed and scope of deglaciation globally. Research published in 2014 suggests that below Greenland's Russell Glacier's ice sheet, methanotrophs could serve as a biological methane sink for the subglacial ecosystem, the region was at least during the sample time, a source of atmospheric methane. Based on dissolved methane in water samples, Greenland may represent a significant global methane source, may contribute more due to ongoing deglaciation. A study in 2016 concluded based on past evidence, that below Greenland's and Antarctica's ice sheet may exist methane clathrates. At every scale, climate influences the condition of ice on Earth's surface. In colder periods massive ice sheets may extend toward the Equator, while in periods warmer than today, the Earth may be free of ice. A significant, empirically demonstrated, positive relationship exists between the surface temperature and concentration of Greenhouse gases such as CO2 in the atmosphere.
The higher concentration, in turn, has a drastic negative impact on the global extent and stability of the cryosphere. On the millennial time scales of Pleistocene glacial and interglacial cycles, the pacemaker of glaciation onset and melting are changes in orbital parameters termed the Milankovitch cycles. Low summer insolation in the northern hemisphere permits growth of ice sheets, while high summer insolation causes more ablation than winter snow accumulation. Human activities promoting climate change, notably the extensive use of fossil fuels over the last 150 years and the resulting increase in atmospheric CO2 concentrations, are the principal cause of the more rapid retreat of alpine glaciers and continental ice sheets all across the world. For example, the West Antarctic Ice Sheet has receded and is now contributing to a positive feedback loop that threatens further deglaciation or collapse. Newly exposed areas of the Southern Ocean contain long-sequestered stores of CO2 which are now being emitted into the atmosphere and are continuing to impact glacial dynamics.
The principle of isostasy applies directly to the process of deglaciation post-glacial rebound, one of main mechanisms through which isostasy is observed and studied. Post-glacial rebound refers to the increase in tectonic uplift activity following glacial retreat. Increased rates and abundance of volcanic activity have been found in regions experiencing post-glacial rebound. If on a large enough scale, an increase in volcanic activity provides a positive feedback to the process of deglaciation as a result CO2 and methane released from volcanos. Periods of deglaciation are caused in part by oceanic processes. For example, interruptions of the usual deep cold water circulation and penetration depths in the North Atlantic have feedbacks that promote further glacial retreat. Deglaciation influences sea level because water held on land in solid form turns into liquid water and drains into the ocean; the recent period of intense deglaciation has resulted in an average global sea level rise of 1.7 mm/year for the entire 20th century, 3.2 mm/year over the past two decades, a rapid increase.
The physical mechanisms by which deglaciation occurs include melting, sublimation and aeolian processes such as w
A glacial period is an interval of time within an ice age, marked by colder temperatures and glacier advances. Interglacials, on the other hand, are periods of warmer climate between glacial periods; the last glacial period ended about 15,000 years ago. The Holocene epoch is the current interglacial. A time with no glaciers on Earth is considered a greenhouse climate state. Within the Quaternary, there have been a number of interglacials; the last glacial period was the most recent glacial period within the Quaternary Ice Age, occurring in the Pleistocene epoch, which began about 110,000 years ago and ended about 15,000 years ago. The glaciations that occurred during this glacial period covered many areas of the Northern Hemisphere and have different names, depending on their geographic distributions: Wisconsin, Midlandian, Würm, Dali, Taibai Luojishan, Tianchi Qomolangma, Llanquihue; the glacial advance reached its maximum extent about 18,000 BP. In Europe, the ice sheet reached Northern Germany.
In the last 650,000 years, there were, on average, seven cycles of glacial retreat. Since orbital variations are predictable, computer models that relate orbital variations to climate can predict future climate possibilities. Work by Berger and Loutre suggests; the amount of heat trapping gases emitted into Earth's Oceans and atmosphere will prevent the next glacial period, which otherwise would begin in around 1,000 years, more glacial cycles