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Antarctic Circumpolar Current

The Antarctic Circumpolar Current is an ocean current that flows clockwise from west to east around Antarctica. An alternative name for the ACC is the West Wind Drift; the ACC is the dominant circulation feature of the Southern Ocean and has a mean transport estimated at 100-150 Sverdrups, or even higher, making it the largest ocean current. The current is circumpolar due to the lack of any landmass connecting with Antarctica and this keeps warm ocean waters away from Antarctica, enabling that continent to maintain its huge ice sheet. Associated with the Circumpolar Current is the Antarctic Convergence, where the cold Antarctic waters meet the warmer waters of the subantarctic, creating a zone of upwelling nutrients; these nurture high levels of phytoplankton with associated copepods and krill, resultant foodchains supporting fish, seals, albatrosses, a wealth of other species. The ACC has been known to sailors for centuries. Jack London's story "Make Westing" and the circumstances preceding the mutiny on the Bounty poignantly illustrate the difficulty it caused for mariners seeking to round Cape Horn westbound on the clipper ship route from New York to California.

The eastbound clipper route, the fastest sailing route around the world, follows the ACC around three continental capes – Cape Agulhas, South East Cape, Cape Horn. The current creates the Weddell gyres; the ACC connects the Atlantic and Indian Oceans, serves as a principal pathway of exchange among them. The current is constrained by landform and bathymetric features. To trace it starting arbitrarily at South America, it flows through the Drake Passage between South America and the Antarctic Peninsula and is split by the Scotia Arc to the east, with a shallow warm branch flowing to the north in the Falkland Current and a deeper branch passing through the Arc more to the east before turning to the north. Passing through the Indian Ocean, the current first retroflects the Agulhas Current to form the Agulhas Return Current before it is split by the Kerguelen Plateau, moving northward again. Deflection is seen as it passes over the mid-ocean ridge in the Southeast Pacific; the current is accompanied by three fronts: the Subantarctic front, the Polar front, the Southern ACC front.

Furthermore, the waters of the Southern Ocean are separated from the warmer and saltier subtropical waters by the subtropical front. The northern boundary of the ACC is defined by the northern edge of the SAF, this being the most northerly water to pass through Drake Passage and therefore be circumpolar. Much of the ACC transport is carried in this front, defined as the latitude at which a subsurface salinity minimum or a thick layer of unstratified Subantarctic mode water first appears, allowed by temperature dominating density stratification. Still further south lies the PF, marked by a transition to cold fresh, Antarctic Surface Water at the surface. Here a temperature minimum is allowed by salinity dominating density stratification, due to the lower temperatures. Farther south still is the SACC, determined as the southernmost extent of Circumpolar Deep Water; this water mass flows along the shelfbreak of the western Antarctic Peninsula and thus marks the most southerly water flowing through Drake Passage and therefore circumpolar.

The bulk of the transport is carried in the middle two fronts. The total transport of the ACC at Drake Passage is estimated to be around 135 Sv, or about 135 times the transport of all the world's rivers combined. There is a small addition of flow in the Indian Ocean, with the transport south of Tasmania reaching around 147 Sv, at which point the current is the largest on the planet; the circumpolar current is driven by the strong westerly winds in the latitudes of the Southern Ocean. In latitudes where there are continents, winds blowing on light surface water can pile up light water against these continents, but in the Southern Ocean, the momentum imparted to the surface waters cannot be offset in this way. There are different theories on how the Circumpolar Current balances the momentum imparted by the winds; the increasing eastward momentum imparted by the winds causes water parcels to drift outward from the axis of the Earth's rotation as a result of the Coriolis force. This northward Ekman transport is balanced by a southward, pressure-driven flow below the depths of the major ridge systems.

Some theories connect these flows directly, implying that there is significant upwelling of dense deep waters within the Southern Ocean, transformation of these waters into light surface waters, a transformation of waters in the opposite direction to the north. Such theories link the magnitude of the Circumpolar Current with the global thermohaline circulation the properties of the North Atlantic. Alternatively, ocean eddies, the oceanic equivalent of atmospheric storms, or the large-scale meanders of the Circumpolar Current may directly transport momentum downward in the water column; this is because such flows can produce a net southward flow in the troughs and a net northward flow over the ridges without requiring any transformation of density. In practice both the thermohaline and the eddy/meander mechanisms are to be important; the current flows at a rate of about 4 km/h over the Macquarie Ridge south of New Zealand. The ACC varies with time. Evidence of this is the Antarctic Circumpolar Wave, a periodi

Phelipe Rodrigues

Phelipe Andrews Melo Rodrigues is a paralympic swimmer from Brazil competing in category S10 events. He had two surgeries when he was just four weeks old. After his second surgery when his foot was in the right position he had an infection which made under his knee and specially his tendon stop to grown disabling his right foot movements so as weakness from his knee below, he started swimming. He tried many different sports but his passion since a child was swimming, his first competitions was for "Academia Movimento" located in Olinda-PE, he competed for 4 years for his team, in 2007 he moved to João Pessoa - PB and joined the state team C. I. E. F. Where he archived regional gold medals and twice 3rd place at nationals competitions with able bodied swimmers. Phelipe was part of the Brazilian team. There he competed in the 100-metre and 50-metre freestyle events where he won silver behind compatriot Andre Brasil, he swam 400-metre freestyle where he failed to make the final, competed as part of the Brazilian 4 × 100 m freestyle and 4 × 100 m medley teams but with the gold and silver medal winning S10 swimmers Brazil could not manage to win a medal finishing fourth and eighth respectively.

On his next Paralympic Game at London 2012 he archived another silver medal in the 100-metre freestyle, fourth place in the 50-metre freestyle event which gave him a medal in Beijing 2008 and fifth in the 100-metre butterfly. He participated in the Para-Panamerican Games in Guadalajara - Mexico in 2011 where he took 5 medals, 3 silver medals and 2 gold medals. Following the 2012 Paralympics Rodrigues accepted an invitation to train in Manchester, where he stayed until the end of 2014 before returning to Brazil. At the 2016 Rio Paralympics Rodrigues won two silver and two bronze medals

Shehryar Khan Afridi

Shehryar Khan Afridi (Urdu: شہریار خان آفریدی‎. He has been a member of the National Assembly of Pakistan since August 2018, he was a member of the National Assembly from June 2013 to May 2018. He is serving as the Minister of State for States and Frontier Regions since 18 April 2019, he was given an additional charge of the Ministry of Narcotics Control after the death of Ali Mohammad Mahar He was born on 12 March 1971. He received a master's degree in International Relations from the University of Peshawar, he wanted to join the Civil Services of Pakistan but was not selected as he failed in the examination. Afridi ran for the seat of National Assembly of Pakistan as an independent candidate from Constituency NA-14 in 2002 Pakistani general election but was unsuccessful, he lost the seat to a candidate of Muttahida Majlis-e-Amal. Afridi was elected to the National Assembly as a candidate of Pakistan Tehreek-e-Insaf from Constituency NA-14 in 2013 Pakistani general election, he defeated a candidate of Jamiat Ulema-e Islam.

He was re-elected to the National Assembly as a candidate of PTI from Constituency NA-32 in 2018 Pakistani general election. He received 82,248 votes and defeated Gohar Mohammad Khan Bangash, a candidate of Muttahida Majlis-e-Amal. On 28 August 2018, he was named by Imran Khan as Minister of State for Interior. On 31 August 2018, he was sworn in as Minister of State for Interior in the federal cabinet of Prime Minister Imran Khan. On 18 April 2019, he resigned as Minister of state for interior, was appointed as the minister of state for States and Frontier regions, he was given the additional portfolio of Ministry of Narcotics Control. In October 2018, Afridi was accused of using public funds worth millions of rupees to renovate and redecorate his new residence. Following which Prime Minister Imran Khan took notice of the issue and ordered Federal Investigation Agency to carry out the investigation