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Iceberg B-9 was an iceberg that calved from the eastern Ross Ice Shelf between Roosevelt Island and King Edward VII Land in Antarctica in October 1987. The iceberg measured long and wide with a total area of .〔 It is one of the longest icebergs ever recorded.〔 The calving took place immediately east of the calving site of Iceberg B-15 and carried away Little America V.〔 Starting in October 1987, Iceberg B-9 drifted for 22 months and covered on its journey.〔 Initially, B-9 moved northwest for seven months before being southward by a subsurface current that eventually led to its colliding with the Ross Ice Shelf in August 1988.〔 It then made a radius gyre before continuing its northwest drift. B-9 moved at an average speed of per day over the continental shelf, as measured by NOAA-10 and DMSP satellite positions, and the ARGOS data buoy positions.〔 In early August 1989, B-9 broke into three large pieces north of Cape Adare.〔 The largest of these three pieces, named Iceberg B-9B, measured long. This new iceberg drifted toward the Mertz Glacier on the George V Coast, where it came to rest next to the glacier and remained there for eighteen years. On 12 or 13 February 2010, Iceberg B-9B collided with the giant floating Mertz Glacier tongue and shaved off a new iceberg that measured long and wide. The two icebergs then began drifting together about off the eastern coast of Antarctica.〔 By December 2011, Iceberg B-9B had made its way into Commonwealth Bay and had broken up into three major pieces, parts of which were frozen to the seabed. The huge iceberg prevented three tourist ships from reaching Antarctica to mark the centenary of the epic polar voyage of Australian explorer Douglas Mawson, who landed at Cape Denison on 8 January 1912 and constructed a complex of huts that remain standing to this day.〔 The three tourist ships attempted to reach the cape but had to turn back due to unusually harsh conditions caused by B-9B's position in the bay. A spokeswoman from the Australian government's Antarctic division observed, "There () unusual ice conditions ... affecting all the tourist ships that are going down there because the tourist ships don't have ice-breaking capabilities, and they also don't have choppers, so their ability to get anywhere near that Mawson's huts area is basically stopped."〔 Iceberg B-9B could remain in Commonwealth Bay for the next decade.〔 ==See also== *List of recorded icebergs by area 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Iceberg B-9」の詳細全文を読む スポンサード リンク
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