The Indian Ocean is the third largest of the world's oceanic divisions, covering 70,560,000 km2. It is bounded by Asia on the north, on the west by Africa, on the east by Australia, on the south by the Southern Ocean or, depending on definition, by Antarctica; the Indian Ocean is named after India. Called the Sindhu Mahasagara or the great sea of the Sindhu by the Ancient Indians, this ocean has been variously called Hindu Ocean, Indic Ocean, etc. in various languages. The Indian Ocean was known earlier as the Eastern Ocean; the term was still in use during the mid-18th century. The borders of the Indian Ocean, as delineated by the International Hydrographic Organization in 1953 included the Southern Ocean but not the marginal seas along the northern rim, but in 2000 the IHO delimited the Southern Ocean separately, which removed waters south of 60°S from the Indian Ocean, but included the northern marginal seas. Meridionally, the Indian Ocean is delimited from the Atlantic Ocean by the 20° east meridian, running south from Cape Agulhas, from the Pacific Ocean by the meridian of 146°49'E, running south from the southernmost point of Tasmania.
The northernmost extent of the Indian Ocean is 30° north in the Persian Gulf. The Indian Ocean covers 70,560,000 km2, including the Red Sea and the Persian Gulf but excluding the Southern Ocean, or 19.5% of the world's oceans. The ocean's continental shelves are narrow. An exception is found off Australia's western coast; the average depth of the ocean is 3,890 m. Its deepest point is Sunda Trench at a depth of 7,450 m. North of 50° south latitude, 86% of the main basin is covered by pelagic sediments, of which more than half is globigerina ooze; the remaining 14% is layered with terrigenous sediments. Glacial outwash dominates the extreme southern latitudes; the major choke points include Bab el Mandeb, Strait of Hormuz, the Lombok Strait, the Strait of Malacca and the Palk Strait. Seas include the Gulf of Aden, Andaman Sea, Arabian Sea, Bay of Bengal, Great Australian Bight, Laccadive Sea, Gulf of Mannar, Mozambique Channel, Gulf of Oman, Persian Gulf, Red Sea and other tributary water bodies.
The Indian Ocean is artificially connected to the Mediterranean Sea through the Suez Canal, accessible via the Red Sea. All of the Indian Ocean is in the Eastern Hemisphere and the centre of the Eastern Hemisphere, the 90th meridian east, passes through the Ninety East Ridge. Marginal seas, gulfs and straits of the Indian Ocean include: Several features make the Indian Ocean unique, it constitutes the core of the large-scale Tropical Warm Pool which, when interacting with the atmosphere, affects the climate both regionally and globally. Asia prevents the ventilation of the Indian Ocean thermocline; that continent drives the Indian Ocean monsoon, the strongest on Earth, which causes large-scale seasonal variations in ocean currents, including the reversal of the Somali Current and Indian Monsoon Current. Because of the Indian Ocean Walker circulation there is no continuous equatorial easterlies. Upwelling occurs near the Horn of Africa and the Arabian Peninsula in the Northern Hemisphere and north of the trade winds in the Southern Hemisphere.
The Indonesian Throughflow is a unique Equatorial connection to the Pacific. The climate north of the equator is affected by a monsoon climate. Strong north-east winds blow from October until April. In the Arabian Sea the violent Monsoon brings rain to the Indian subcontinent. In the southern hemisphere, the winds are milder, but summer storms near Mauritius can be severe; when the monsoon winds change, cyclones sometimes strike the shores of the Arabian Sea and the Bay of Bengal. The Indian Ocean is the warmest ocean in the world. Long-term ocean temperature records show a rapid, continuous warming in the Indian Ocean, at about 0.7–1.2 °C during 1901–2012. Indian Ocean warming is the largest among the tropical oceans, about 3 times faster than the warming observed in the Pacific. Research indicates that human induced greenhouse warming, changes in the frequency and magnitude of El Niño events are a trigger to this strong warming in the Indian Ocean. South of the Equator the Indian Ocean is gaining heat from June to October, during the austral winter, while it is losing heat from November to March, during the austral summer.
Among the few large rivers flowing into the Indian Ocean are the Zambezi and Jubba in Africa. The ocean's currents are controlled by the monsoon. Two large gyres, one in the northern hemisphere flowing clockwise and one south of the equator moving anticlockwise, constitute the dominant flow pattern. During the winter monsoon, circulation is reversed north of 30°S and winds are weakened during winter and the transitional periods between the monsoons. Deep water circulation is controlled by inflows from the Atlantic Ocean, the Red Sea, Antarctic currents. North of 20 ° south latitude the minimum surface temperature is 22 °C. Southward of 40° south latitude, temperatures
Bar-class boom defence vessel
The Bar class were a class of boom defence vessels of the Royal Navy and Royal Australian Navy during World War II. HMS Barbain HMS Barbarian HMS Barbastel HMS Barberry HMS Barbette HMS Barbette HMS Barbican HMS Barbour HMS Barbourne HMS Barbrake HMS Barbridge HMS Barbrook HMS Barcarole HMS Barcastle HMS Barcliff HMS Barclose HMS Barcock HMS Barcombe HMS Barcote HMS Barcroft HMS Bardell HMS Bardolf HMS Barfair HMS Barfield HMS Barfoam HMS Barfoil HMS Barfoot HMS Barford HMS Barfoss HMS Barfount HMS Barglow HMS Barhill HMS Barholm HMS Barilla HMS Baritone HMS Barking HMS Barkis HMS Barlake HMS Barlane HMS Barleycorn HMS Barlight HMS Barlow HMS Barmill HMS Barmond HMS Barmouth HMS Barnaby HMS Barnard HMS Barndale HMS Barneath HMS Barnehurst HMS Baron HMS Baronia HMS Barrage HMS Barranca HMS Barrhead HMS Barricade HMS Barrier HMS Barrington HMS Barrymore HMS Barsing HMS Barsound HMS Barspear HMS Barstoke HMS Barthorpe HMS Bartizan HMS Barwell HMS Barwind HMS Barcross HMS Barflake HMS Barnstone HMS Barova SAS Somerset is a museum ship in South Africa HMAS Karangi is the only survivor on the RAN fleet in Homebush Bay as an abandoned wreck.
Notes Bibliographyhttp://uboat.net/allies/warships/class.html? ID=326 http://uboat.net/allies/warships/class.html? ID=372&navy=HMS
Darwin, Northern Territory
Darwin is the capital city of the Northern Territory of Australia, situated on the Timor Sea. It is the largest city in the sparsely populated Northern Territory, with a population of 145,916, it is the smallest and most northerly of the Australian capital cities, acts as the Top End's regional centre. Darwin's proximity to South East Asia makes it a link between Australia and countries such as Indonesia and East Timor; the Stuart Highway begins in Darwin, extends southerly across central Australia through Tennant Creek and Alice Springs, concluding in Port Augusta, South Australia. The city is built upon a low bluff overlooking the harbour, its suburbs begin at Lee Point in the stretch to Berrimah in the east. Past Berrimah, the Stuart Highway goes on to its suburbs; the Darwin region, like much of the Top End, experiences a tropical climate with a wet and dry season. A period known locally as "the build up" leading up to Darwin's wet season sees temperature and humidity increase. Darwin's wet season arrives in late November to early December and brings with it heavy monsoonal downpours, spectacular lightning displays, increased cyclone activity.
During the dry season, the city has clear skies and mild sea breezes from the harbour. The greater Darwin area is the ancestral home of the Larrakia people. On 9 September 1839, HMS Beagle sailed into Darwin harbour during its survey of the area. John Clements Wickham named the region "Port Darwin" in honour of their former shipmate Charles Darwin, who had sailed with them on the ship's previous voyage which ended in October 1836; the settlement there became the town of Palmerston in 1869, but it was renamed Darwin in 1911. The city has been entirely rebuilt four times, following devastation caused by the 1897 cyclone, the 1937 cyclone, Japanese air raids during World War II, Cyclone Tracy in 1974; the Aboriginal people of the Larrakia language group are the traditional custodians and the first inhabitants of the greater Darwin area. They had trading routes with Southeast Asia, imported goods from as far afield as South and Western Australia. Established songlines penetrated throughout the country, allowing stories and histories to be told and retold along the routes.
The extent of shared songlines and history of multiple clan groups within this area is still contestable. The Dutch visited Australia's northern coastline in the 1600s and landed on the Tiwi Islands only to be repelled by the Tiwi peoples; the Dutch created the first European maps of the area. This accounts for the Dutch names such as Arnhem Land and Groote Eylandt; the first British person to see Darwin harbour appears to have been Lieutenant John Lort Stokes of HMS Beagle on 9 September 1839. The ship's captain, Commander John Clements Wickham, named the port after Charles Darwin, the British naturalist who had sailed with them both on the earlier second expedition of the Beagle. In 1863, the Northern Territory was transferred from New South Wales to South Australia. In 1864 South Australia sent B. T. Finniss north as Government Resident to survey and found a capital for its new territory. Finniss chose a site at Escape Cliffs, near the entrance to Adelaide River, about 60 kilometres northeast of the modern city.
This attempt was short-lived and the settlement abandoned by 1865. On 5 February 1869, George Goyder, the Surveyor-General of South Australia, established a small settlement of 135 people at Port Darwin between Fort Hill and the escarpment. Goyder named the settlement Palmerston, after the British Prime Minister Lord Palmerston. In 1870, the first poles for the Overland Telegraph were erected in Darwin, connecting Australia to the rest of the world; the discovery of gold by employees of the Australian Overland Telegraph Line digging holes for telegraph poles at Pine Creek in the 1880s spawned a gold rush which further boosted the young colony's development. In February 1872 the brigatine Alexandra was the first private vessel to set sail from an English port directly to Darwin, carrying people many of whom were coming to recent gold finds. In early 1875 Darwin's white population had grown to 300 because of the gold rush. On 17 February 1875 the SS Gothenburg left Darwin en route for Adelaide.
The 88 passengers and 34 crew included government officials, circuit-court judges, Darwin residents taking their first furlough, miners. While travelling south along the north Queensland coast, the Gothenburg encountered a cyclone-strength storm and was wrecked on a section of the Great Barrier Reef. Only 22 men survived, while between 112 people perished. Many passengers who perished were Darwin residents and news of the tragedy affected the small community, which took several years to recover. In the 1870s large numbers of Chinese settled at least temporarily in the Northern Territory. By 1888 there were 6122 Chinese in the Northern Territory in or around Darwin; the early Chinese settlers were from the Kwantung Province in south China. However at the end of the nineteenth century anti-Chinese feelings grew in response to the 1890s economic depression and the White Australia policy meant many Chinese left the Territory. However, some families stayed and became Australian citizens, established a commercial base in Darwin.
Darwin became the city's official name in 1911. The period between 1911 and 1919 was filled with political turmoil with trade union unrest, which culminated on 17 December 1918. Led by Harold Nelson, some 1000 demonstrators marched to Government House at Liberty
QF 4-inch naval gun Mk XIX
The QF 4-inch Mk XIX gun was a British low-velocity 4-inch 40-calibre naval gun used to arm small warships such as Bathurst and Castle-class corvette and some River-class frigate in World War II against submarines. It succeeded the higher-velocity World War I-era BL 4-inch Mk IX; the Mk XIX fired fixed ammunition, 38.5 inches long and weighed 50 pounds. The weight of the projectile was increased from 31 pounds for the Mk IX to 35 pounds for the Mk XIX; the high-angle mounting used for the XIX added some anti-aircraft capability and allowed it to fire starshells to illuminate the battle area at night. On HMAS Castlemaine at Williamstown, Australia. On the parade ground at the Irish Naval Service Base, Haulbowline, Co. Cork, Ireland John Campbell, "Naval Weapons Of World War Two", Annapolis: Naval Institute Press, 1985, ISBN 0-87021-459-4 Tony DiGiulian, Britain 4"/40 QF Mark XIX
In the 18th century and most of the 19th, a sloop-of-war in the Royal Navy was a warship with a single gun deck that carried up to eighteen guns. The rating system covered all vessels above. In technical terms the more specialised bomb vessels and fireships were classed as sloops-of-war, in practice these were employed in the sloop role when not carrying out their specialized functions. In World War I and World War II, the Royal Navy reused the term "sloop" for specialized convoy-defence vessels, including the Flower class of World War I and the successful Black Swan class of World War II, with anti-aircraft and anti-submarine capability. A sloop-of-war was quite different from a civilian or mercantile sloop, a general term for a single-masted vessel rigged in a way that would today be called a gaff cutter, though some sloops of that type did serve in the 18th century British Royal Navy on the Great Lakes of North America. In the first half of the 18th century, most naval sloops were two-masted vessels carrying a ketch or a snow rig.
A ketch had main and mizzen masts but no foremast, while a snow had a foremast, a main mast and a mizzen abaft the lower main mast. The first three-masted sloops appeared during the 1740s, from the mid-1750s most new sloops were built with a three-masted rig; the third sail the ability to back sail. In the 1770s, the two-masted sloop re-appeared in a new guise as the brig sloop, the successor to the former snow sloops. Brig sloops had two masts. In the Napoleonic period, Britain built huge numbers of brig sloops of the Cruizer class and the Cherokee class; the brig rig was economical of manpower and, when armed with carronades, they had the highest ratio of firepower to tonnage of any ships in the Royal Navy. The carronades used much less manpower than the long guns used to arm frigates; the Cruizer class were used as cheaper and more economical substitutes for frigates, in situations where the frigates' high cruising endurance was not essential. A carronade-armed brig, would be at the mercy of a frigate armed with long guns, so long as the frigate manoeuvered to exploit its superiority of range.
The other limitation of brig sloops as opposed to post ships and frigates was their restricted stowage for water and provisions, which made them less suitable for long-range cruising. However, their shallower draught made them excellent raiders against coastal shipping and shore installations; the Royal Navy made extensive use of the Bermuda sloop, both as a cruiser against French privateers and smugglers, as its standard advice vessels, carrying communications, vital persons and materials, performing reconnaissance duties for the fleets. Bermuda sloops were found with mixtures of gaff and square rig, or a Bermuda rig, they were built with up to three masts. The single masted ships, with their huge sails, the tremendous wind energy they harnessed, were demanding to sail, required large, experienced crews; the Royal Navy favoured multi-masted versions as it was perennially short of sailors, at the end of the 18th century, such personnel as it had in the Western Atlantic, received insufficient training.
The longer decks of the multi-masted vessels had the advantage of allowing more guns to be carried. A sloop-of-war was smaller than a sailing frigate and was outside the rating system. In general, a sloop-of-war would be under the command of a master and commander rather than a post captain, although in day-to-day use at sea the commanding officer of any naval vessels would be addressed as "captain". A ship sloop was the equivalent of the smaller corvette of the French Navy; the name corvette was subsequently applied to British vessels, but not until the 1830s. American usage, while similar to British terminology into the beginning of the 19th century diverged. By about 1825 the United States Navy used "sloop-of-war" to designate a flush-deck ship-rigged warship with all armament on the gundeck; the Americans occasionally used the French term corvette. In the Royal Navy, the sloop evolved into an unrated vessel with a single gun deck and three masts, two square rigged and the aftermost fore-and-aft rigged.
Steam sloops had a transverse division of their lateral coal bunkers in order that the lower division could be emptied first, to maintain a level of protection afforded by the coal in the upper bunker division along the waterline. During the War of 1812 sloops of war in the service of the United States Navy performed well against their Royal Navy equivalents; the American ships had the advantage of being ship
Bendigo is a city in Victoria, located near the geographical centre of the state and 150 kilometres north west of the state capital, Melbourne. As of June 2016, Bendigo had an urban population of 95,587, making it the fourth-largest inland city in Australia and fourth-most populous city in the state, it is the administrative centre for the City of Greater Bendigo, which encompasses both the urban area and outlying towns spanning an area around 3,000 km2 and over 111,000 people. The discovery of gold in the soils of Bendigo during the 1850s made it one of the most significant Victorian-era boomtowns in Australia. News of the finds intensified the Victorian gold rush, bringing an influx of migrants to the city from around the world within a year and transforming it from a sheep station to a major settlement in the newly proclaimed Colony of Victoria. Once the alluvial gold had been mined out, mining companies were formed to exploit the rich underground quartz reef gold. Since 1851, about 780,000 kilograms of gold have been extracted from Bendigo's goldmines, making it the highest producing goldfield in Australia in the 19th century and the largest gold-mining economy in eastern Australia.
It is notable for its Victorian architectural heritage. The city took its name from the Bendigo Creek and its residents from the earliest days of the gold rush have been called "Bendigonians". Although the town flourished in its beginnings as a result of the discovery of gold, it experienced a reversal of fortune in the early 20th century. However, its growth accelerated in the postwar years and has continued to increase since; the original inhabitants of the Mount Alexander area that includes Greater Bendigo were the Dja Dja Wurrung people, who exploited the rich local hunting grounds. These grounds were noticed by white settlers, who established the first of many vast sheep runs in 1837; the Mount Alexander North sheep run was bordered by a creek that came to be known as Bendigo, after a local shepherd nicknamed for the English bare-knuckle prizefighter William Abednego Thompson. Gold was discovered in the area in September 1851, just after the other significant goldfields in neighbouring Castlemaine, from where many diggers migrated, bringing the total to 40,000 in less than a year.
In 1853, a massive protest was held over the cost of the licence fee for prospectors, though it passed off peacefully, due to good diplomacy by police and miners’ leaders. From being a tent city, the boomtown grew into a major urban centre with many grand public buildings; the municipality became a borough in 1863 known as Sandhurst until 1891, but always unofficially as Bendigo. The railway had reached here by 1862, stimulating rapid growth, with flour mills, woollen mills, quarries, eucalyptus oil production, food production industries, timber cutting; when the alluvial gold ran out, the gold fields evolved into major mines with deep shafts to mine the quartz-based gold. Bendigo was declared a city in 1871. Rapid population growth brought a water shortage solved with a new viaduct that harnessed the Coliban River; the architect William Charles Vahland left an important mark on Bendigo during this period. He is credited with the popular cottage design with verandahs decorated in iron lace, a style, soon adopted right across the state of Victoria.
Vahland designed more than 80 buildings, including the Alexandra Fountain, arguably the most prominent monument in Bendigo, with its granite dolphins, unicorns and allegorical figures. A tram network was in use by 1890. After a temporary drop in population, renewed growth occurred from the 1930s, as the city consolidated as a manufacturing and regional service centre, though gold mining continued until 1954. Recent growth has been most concentrated in areas such as Epsom, Kangaroo Flat and Strathfieldsaye. In 1994, the City of Bendigo was abolished and merged with the Borough of Eaglehawk, the Huntly and Strathfieldsaye shires, the Rural City of Marong to form the larger City of Greater Bendigo; the population of the city increased from around 78,000 in 1991 to about 100,617 in 2012. Bendigo is one of the fastest-growing regional centres in Victoria; the city is surrounded by components of the Greater Bendigo National Park, as well as the Bendigo Box-Ironbark Region Important Bird Area, identified as such by BirdLife International because of its importance for swift parrots and other woodland birds.
A dozen species of insect-eating bats and the pollinating grey-headed flying fox inhabit the area. Bendigo has a dry temperate climate with warm to hot summers and cool to cold winters. Under the Köppen-Geiger classification, it lies on a humid subtropical/oceanic transitional climate zone, due to its location being on the boundary of the hot, sultry inland areas to the north and the cool, damp Southern Ocean to the south. Bendigo gets 109.9 clear days annually. The mean minimum temperature in January is 14.3 °C and the maximum 28.7 °C, although temperatures above 35 °C are reached. The highest temperature recorded was 45.4 °C, during the early 2009 southeastern Australia heat wave. There is a disputed recording of 47.4 °C. The mean minimum temperature in July is 3.5 °C and winter minima below 0 °C are recorded 28 nights per year on average. Mean maximum winter temperatures in July are 12.1 °C. Most of the city's annual rainfall of 582.1 millimetres falls between September. Snowfalls are unknown.
People's Liberation Army Navy
The People's Liberation Army Navy known as the PLA Navy, is the naval warfare branch of the People's Liberation Army, the armed wing of the Communist Party of China and, by default, the national armed forces of the People's Republic of China. The PLAN can trace its lineage to naval units fighting during the Chinese Civil War and was established in September 1950. Throughout the 1950s and early 1960s, the Soviet Union provided assistance to the PLAN in the form of naval advisers and export of equipment and technology; until the late 1980s, the PLAN was a riverine and littoral force. However, by the 1990s, following the fall of the Soviet Union and a shift towards a more forward-oriented foreign and security policy, the leaders of the Chinese military were freed from worrying over land border disputes, instead turned their attention towards the seas; this led to the development of the People's Liberation Army Navy into a green-water navy by 2009. Before the 1990s the PLAN had traditionally played a subordinate role to the People's Liberation Army Ground Force.
In 2008, General Qian Lihua confirmed that China plans to operate a small fleet of aircraft carriers in the near future, but for the purpose of regional defence as opposed to "global reach". As of 2013 PLA officials have outlined plans to operate in the first and second island chains. Chinese strategists term the development of the PLAN from a green-water navy into "a regional blue-water defensive and offensive navy."The People's Liberation Army Navy is composed of five branches. With a personnel strength of 255,000 servicemen and women, including 10,000 marines and 26,000 naval air force personnel, it is the second largest navy in the world in terms of tonnage, only behind the United States Navy, has the largest number of major combatants of any navy; the PLAN traces its lineage to units of the Republic of China Navy who defected to the People's Liberation Army towards the end of the Chinese Civil War. In 1949, Mao Zedong asserted that "to oppose imperialist aggression, we must build a powerful navy".
During the Landing Operation on Hainan Island, the communists used wooden junks fitted with mountain guns as both transport and warships against the ROCN. The Naval Academy was set up at Dalian on 22 November 1949 with Soviet instructors; the navy was established in September 1950 by consolidating regional naval forces under Joint Staff Department command in Jiangyan. It consisted of a motley collection of ships and boats acquired from the Kuomintang forces; the Naval Air Force was added two years later. By 1954 an estimated 2,500 Soviet naval advisers were in China—possibly one adviser to every thirty Chinese naval personnel—and the Soviet Union began providing modern ships. With Soviet assistance, the navy reorganized in 1954 and 1955 into the North Sea Fleet, East Sea Fleet, South Sea Fleet, a corps of admirals and other naval officers was established from the ranks of the ground forces. In shipbuilding the Soviets first assisted the Chinese the Chinese copied Soviet designs without assistance, the Chinese produced vessels of their own design.
Soviet assistance progressed to the point that a joint Sino-Soviet Pacific Ocean fleet was under discussion. Through the upheavals of the late 1950s and 1960s the Navy remained undisturbed. Under the leadership of Minister of National Defense Lin Biao, large investments were made in naval construction during the frugal years after the Great Leap Forward. During the Cultural Revolution, a number of top naval commissars and commanders were purged, naval forces were used to suppress a revolt in Wuhan in July 1967, but the service avoided the turmoil affecting the country. Although it paid lip service to Mao and assigned political commissars aboard ships, the Navy continued to train and maintain the fleets as well the coastal defense and aviation arms, as well as in the performance of its mission. In the 1970s, when 20 percent of the defence budget was allocated to naval forces, the Navy grew dramatically; the conventional submarine force increased from 35 to 100 boats, the number of missile-carrying ships grew from 20 to 200, the production of larger surface ships, including support ships for oceangoing operations, increased.
The Navy began development of nuclear attack submarines and nuclear-powered ballistic missile submarines. In the 1980s, under the leadership of Chief Naval Commander Liu Huaqing, the navy developed into a regional naval power, though naval construction continued at a level somewhat below the 1970s rate. Liu Huaqing was an Army Officer who spent most of his career in administrative positions involving science and technology, it was not until 1988. Liu was very close to Deng Xiaoping as his modernization efforts were much in keeping with Deng's national policies. While under his leadership Naval construction yards produced fewer ships than the 1970s, greater emphasis was placed on technology and qualitative improvement. Modernization efforts encompassed higher educational and technical standards for personnel. Examples of the expansion of China's capabilities were the 1980 recovery of an intercontinental ballistic missile in the Western Pacific by a twenty-ship fleet, extended naval operations in th