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42-487: The Ross Ice Shelf covers over 487,000 square kilometres (188,000 sq mi). Windless Bight is a large ice plain that covers hundreds of square kilometers of the northwest edge of the Ross Ice Shelf. It is flat and featureless, and has hardly any surface winds, as its name implies. Ross Island as a whole experiences strongly southerly winds, but Windless Bight is unusually calm. The bight extends from Castle Rock on

84-484: A first exploration of the area by the Discovery Expedition in 1901–1904, Robert Falcon Scott made a significant study of the shelf and its surroundings from his expedition's base on Ross Island . By measurement of calved ice bergs and their buoyancy, he estimated the ice sheet to be on average 274 meters thick; the undisturbed morphology of the ice sheet and its inverted temperature profile led him to conclude it

126-503: A large southern portion of the Ross Sea and the entire Roosevelt Island located in the east of the Ross Sea. The ice shelf is named after Sir James Clark Ross , who discovered it on 28 January 1841. It was originally called "The Barrier", with various adjectives including " Great Ice Barrier ", as it prevented sailing further south. Ross mapped the ice front eastward to 160° W. In 1947,

168-662: The Hut Point Peninsula east to Terror Point. Mount Erebus is to the northwest, Mount Terra Nova to the north and Mount Terror to the northeast. Cape Crozier is east of the bight. The Preparatory Commission for the Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO) has its IS55 infrasonic array on Windless Bight about 26 kilometres (16 mi) northeast of McMurdo Station . The lack of surface winds reduces background noise that might interfere with infrasound measurement. This

210-470: The 2022 Hunga Tonga–Hunga Ha'apai eruption and tsunami . McMurdo Ice Shelf The McMurdo Ice Shelf is the portion of the Ross Ice Shelf bounded by McMurdo Sound and Ross Island on the north and Minna Bluff on the south. Studies show this feature has characteristics quite distinct from the Ross Ice Shelf and merits individual naming. A.J. Heine, who made investigations in 1962–63, suggested

252-604: The Aurora , the ship of the Ross Sea Party of the British expedition under Ernest Shackleton , 1914-17. 77°38′S 167°45′E  /  77.633°S 167.750°E  / -77.633; 167.750 . Steep, mainly ice-covered cliffs, 4 nautical miles (7.4 km; 4.6 mi) long, between Aurora Glacier and Terror Glacier on the south shore of Ross Island. The name is suggested by two prominent V-shape wedges which protrude from

294-797: The New Zealand Geological Survey Antarctic Expedition (NZGSAE), 1962–63, because of its association with Mount Terror. 77°40′S 168°10′E  /  77.667°S 168.167°E  / -77.667; 168.167 . A small bay immediately west-northwest of Terror Point in Windless Bight, on the south side of Ross Island. So named by the Winter Journey Party, led by Wilson of the British Antarctic Expedition (BrAE), 1910-13 , in July 1911 because of

336-522: The cliffs of Dover ". Ross, who in 1831 had located the North Magnetic Pole , spent the next two years vainly searching for a sea passage to the South Pole; later, his name was given to the ice shelf and the sea surrounding it. Two volcanoes in the region were named by Ross for his vessels. For later Antarctic explorers seeking to reach the South Pole, the Ross Ice Shelf became a starting area. In

378-474: The Ross Ice Shelf Project was launched with a plan of drilling into the shelf to sample the biomass in the area and make other determinations about the shelf and its relationship to the sea floor. This is believed to be the first oceanographic ice shelf borehole. The project included surface glaciological observations as well as drilling, and the glaciological portion started during the planning phase of

420-563: The U.S. Board on Geographic Names applied the name "Ross Shelf Ice" to this feature and published it in the original U.S. Antarctic Gazetteer. In January 1953, the name was changed to "Ross Ice Shelf"; that name was published in 1956. On 5 January 1841, the British Admiralty's Ross expedition in the Erebus and the Terror , three- masted ships with specially strengthened wooden hulls ,

462-501: The analyses have resulted in some interesting theories being posited and publicized. One such opinion, given in 2006 based on a geological survey, suggested that the ice shelf had collapsed previously, perhaps suddenly, which could well happen again. A science team from New Zealand installed a camp in the centre of the shelf in late 2017. The expedition was led by glaciologist Christina Hulbe and brought together oceanographers, glaciologists, biologists and sedimentologists to examine

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504-640: The array, along with the weather information, is formatted at the CRF into 30-second packages, which are sent by satellite link from McMurdo Station to Brewster, Washington , Denver , Colorado and Vienna , Austria. A field camp for support personnel is used for several weeks each year. The team has standard remote field equipment such as snowmobiles, and stays in two Polarhavens and six individual mountain tents. During periods of use, one or two team members may return to McMurdo Station to collect supplies, and to stay overnight. Download coordinates as: Named features of

546-460: The bight include, from west to east, Sultans Head Rock, Aurora Glacier, Vee Cliffs, Terror Glacier, Fog Bay and Terror Point. Cape MacKay is east of Terror Point. 77°43′S 167°12′E  /  77.717°S 167.200°E  / -77.717; 167.200 . A rock spur along the east flank of Hut Point Peninsula, 7.5 nautical miles (13.9 km; 8.6 mi) southwest of the Vee Cliffs, on

588-458: The cliff wall. The name was first used by Doctor Edward A. Wilson who, with Thomas V. Hodgson of BrNAE, 1901–04, visited the cliffs in November 1903. 77°37′00″S 168°16′00″E  /  77.6166667°S 168.2666667°E  / -77.6166667; 168.2666667 . A glacier that drains part of the south slopes of Mount Terror in southeast Ross Island. It flows southwest and coalesces with

630-427: The drilling. The drilling portion of the project was to have begun during 1974, but the actual drilling was delayed until 1976. Finally, in 1977, the scientists were able to drill successfully through the ice, making a hole that could be sampled every few days for three weeks. The team was able to map the sea floor, study the tides, and assess the fish and various other forms of life in the waters. The team also examined

672-613: The east margin of Terror Glacier where the two glaciers enter Fog Bay. In association with the names of expedition ships grouped on this island, named after U.S. Coast Guard Cutter (USCGC) Eastwind . An icebreaker, "she" made nine Antarctic deployments in support of science activities from U.S. Navy (USN) Operation Deep Freeze, 1955–56, through the 1966–67 season. 77°37′S 168°03′E  /  77.617°S 168.050°E  / -77.617; 168.050 . A large glacier between Mount Terra Nova and Mount Terror on Ross Island, flowing south into Windless Bight. So named by A.J. Heine of

714-584: The east side of the terminus of Aurora Glacier. Named by Advisory Committee on Antarctic Names (US-ACAN) (2000) in association with Tyree Head, q.v., after Rear Admiral George J. Dufek, United States Navy (United States Navy) (1903-77), Commander, United States Naval Support Force, Antarctica, 1954-59. 77°37′S 167°38′E  /  77.617°S 167.633°E  / -77.617; 167.633 . A large glacier draining that part of Ross Island between Mount Erebus and Mount Terra Nova, and flowing south into McMurdo Ice Shelf . Named by A.J. Heine in 1963 after

756-765: The first humans to cross the Ice Shelf during its failed attempt to reach the South Pole . Both Roald Amundsen and Scott crossed the shelf to reach the Pole in 1911. Amundsen wrote: "Along its outer edge the Barrier shows an even, flat surface; but here, inside the bay, the conditions were entirely different. Even from the deck of the Fram we were able to observe great disturbances of the surface in every direction; huge ridges with hollows between them extended on all sides. The greatest elevation lay to

798-553: The glaciers and others the valleys on the ice shelf. From 1967 to 1972 the Scott Polar Research Institute reported extensive observations using radio echo sounding . The technique allowed measurements to be taken from the air; allowing a criss cross track of 35,000 km to be covered; compared with a 3,000 km track from previous seismic sounding on the ground. More detailed surveys were executed between 1973 and 1978. A significant scientific endeavor called

840-506: The glaciers' surfaces. Once their ice shelves are removed, the glaciers increase in speed due to meltwater percolation and/or a reduction of braking forces, and they may begin to dump more ice into the ocean than they gather as snow in their catchments. Glacier ice speed increases are already observed in Peninsula areas where ice shelves disintegrated in prior years." The Ross Ice Shelf is one of many such shelves. It reaches into Antarctica from

882-545: The grounding line region of the Kamb Ice Stream . The hot water drill borehole at this site penetrated through over 500 m of snow and ice to an ocean cavity only 30 m deep at this location. As well as sampling the ocean and sediment, it was the first deployment beneath the Ross Ice Shelf of the Remotely operated underwater vehicle Icefin developed at Georgia Tech , a vehicle designed around parameters suitable for exploration of

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924-442: The help of tackles? Or a great and dangerous fissure, which we should not be able to cross without going a long way round? We naturally expected something of the sort. This mighty and terrible monster would, of course, offer resistance in some form or other," he wrote. "The mystic Barrier! All accounts without exception, from the days of Ross to the present time, had spoken of this remarkable natural formation with apprehensive awe. It

966-422: The ice, ocean and sediment in the central shelf region. One of the key findings was that the ice in the region was re-freezing. This re-freezing and growth of an ice shelf is not uncommon but the Ross Ice Shelf situation appeared to be very variable as there was no evidence of long-term freezing. A recent study attribute this variability in-part to tidal mixing. A second New Zealand expedition in 2019 traveled to

1008-509: The liquid cavities of places like Europa . The same New Zealand team returned to another site along the Kamb coast in December 2021, this time drilling through an under-ice river that proved to be essentially oceanic. The team were able to melt through the ice to discover the 250 m deep river had formed a relatively narrow channel beneath the ice. They also recorded evidence of the tsunami generated by

1050-711: The name for the ice shelf bounded by Ross Island, Brown Peninsula , Black Island and White Island . The Advisory Committee on Antarctic Names has extended the application of this name to include the contiguous ice shelf southward to Minna Bluff. In March 2010, while scientists were taking photographs of the underside of the ice shelf, they discovered a living Lysianassidae amphipod . 78°S 167°E  /  78°S 167°E  / -78; 167 [REDACTED]  This article incorporates public domain material from "McMurdo Ice Shelf" . Geographic Names Information System . United States Geological Survey . This Scott Coast location article

1092-448: The north, and covers an area of about 520,000 km (200,000 sq mi), nearly the size of France. The ice mass is about 800 km (500 mi) wide and 970 km (600 mi) long. In some places, namely its southern areas, the ice shelf can be almost 750 m (2,450 ft) thick. The Ross Ice Shelf pushes out into the sea at between 1.5 and 3 m (5 and 10 ft) a day. Other glaciers gradually add bulk to it. At

1134-411: The oceanographic and geological conditions as well as the temperature of the ice. They estimated that the base of the shelf was −2.16 °C (27.3 °F). They also made other calculations about the fluctuations of the temperatures. The results of these various projects were published in a series of reports in the 2 February 1979 issue of Science . During the 1980s, a network of weather stations

1176-473: The same time, the freezing of seawater below the ice mass increases the thickness of the ice from 40 to 50 cm (16 to 20 in) . Sometimes, fissures and cracks may cause part of the shelf to break off; the largest known is about 31,000 km (12,000 sq mi), that is, slightly larger than Belgium. Iceberg B-15 , the world's largest recorded iceberg , was calved from the Ross Ice Shelf during March 2000. Scientists have long been intrigued by

1218-466: The shelf and its composition. Many scientific teams researching the Antarctic have made camps on or adjacent to the Ross Ice Shelf. This includes McMurdo Station , built next to the Ross Ice Shelf on volcanic rock. One major effort was a series of studies conducted in 1957 and 1958, which were continued during the 1960–61 season. The efforts involved an international team of scientists. Some parties explored

1260-572: The shelf is "only a few degrees too cool in summer presently to undergo the same kind of retreat process. The Ross Ice Shelf is the main outlet for several major glaciers draining the West Antarctic Ice Sheet , which contains the equivalent of 5 m of sea level rise in its above-sea-level ice." The report added that observations of "iceberg calving " on the Ross Ice Shelf are, in their opinion, unrelated to its stability. Scientific exploration continues to uncover interesting information and

1302-469: The size of France). It is several hundred metres thick. The nearly vertical ice front to the open sea is more than 600 kilometres (370 mi) long, and between 15 and 50 metres (50 and 160 ft) high above the water surface. Ninety percent of the floating ice, however, is below the water surface. Most of the Ross Ice Shelf is in the Ross Dependency claimed by New Zealand. It floats in, and covers,

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1344-562: The south in the form of a lofty, arched ridge, which we took to be about 500 feet [150 m] high on the horizon. But it might be assumed that this ridge continued to rise beyond the range of vision". The next day, the party made its first steps on the Barrier. "After half an hour's march we were already at the first important point—the connection between the sea-ice and the Barrier. This connection had always haunted our brains. What would it be like? A high, perpendicular face of ice, up which we should have to haul our things laboriously with

1386-551: The south side of Ross Island. The headland rises to over 400 metres (1,300 ft) and is ice covered except for rock exposed on the lower east side. Named after Admiral David M. Tyree, United States Navy (d. 1984), Commander, U.S. Naval Support Force, Antarctica, 1959-62. 77°36′53″S 167°42′28″E  /  77.61462°S 167.70785°E  / -77.61462; 167.70785 . An ice-covered headland 4.4 nautical miles (8.1 km; 5.1 mi) northeast of Tyree Head. The headland rises to 620 metres (2,030 ft) high at

1428-501: The south side of Ross Island. The name was first used by the British National Antarctic Expedition (BrNAE) under Scott, 1901-04, in describing rocks collected there by Thomas V. Hodgson of the expedition. 77°39′11″S 167°27′42″E  /  77.652933°S 167.461641°E  / -77.652933; 167.461641 A headland 3.2 nautical miles (5.9 km; 3.7 mi) northeast of Sultans Head Rock on

1470-789: The southeast extremity of Ross Island. Discovered by the BrNAE (1901–04) and named for Captain Harry MacKay, commander of the Terra Nova , one of the relief ships for the expedition. [REDACTED]  This article incorporates public domain material from websites or documents of the United States Geological Survey . Ross Ice Shelf The Ross Ice Shelf is the largest ice shelf of Antarctica (as of 2013 , an area of roughly 500,809 square kilometres (193,363 sq mi) and about 800 kilometres (500 mi) across: about

1512-606: The thick white fog they encountered in this locality. 77°41′S 168°13′E  /  77.683°S 168.217°E  / -77.683; 168.217 . A point below Mount Terror. It marks the east limit of Fog Bay, 4 nautical miles (7.4 km; 4.6 mi) west-northwest of Cape MacKay. The name was first used by members of the BrNAE, 1901–04, and was apparently applied in association with Mount Terror which overlooks this point from northeastward. 77°42′S 168°31′E  /  77.700°S 168.517°E  / -77.700; 168.517 . An ice-covered cape which forms

1554-427: Was as though one could always read between the lines the same sentence: 'Hush, be quiet! the mystic Barrier!' "One, two, three, and a little jump, and the Barrier was surmounted!" Ice shelves are thick plates of ice, formed continuously by glaciers, that float atop an ocean. The shelves act as "brakes" for the glaciers. These shelves serve another important purpose—"they moderate the amount of melting that occurs on

1596-549: Was certified as an International Monitoring System (IMS) station under the Comprehensive Nuclear-Test-Ban Treaty on 22 August 2003. IS55 is an array of eight microbarometer sensors and space filters arranged that is divided into two sub-arrays, plus a high performance weather station at one of the arrays. Every second data on temperature, wind speed and wind direction is transmitted to a Central Recording Facility (CRF). Infrasonic data from each element of

1638-733: Was confirmed by an infrasonic microphone array that was established in 1976 by the Geophysical Institute of the University of Alaska Fairbanks , sponsored by the National Science Foundation (NSF). The University of Alaska Fairbanks, under contract to the CTBTO, prepared the site for the IS55 infrasonic array and installed the equipment, which was completed in February 2001. After testing, IS55

1680-490: Was floating on water; and measurements in 1902–1903 showed it had advanced 555 meters northwards in 13.5 months. The findings were presented at a lecture entitled "Universitas Antarctica!" given 7 June 1911 and were published in the account of Scott's second expedition (the Terra Nova Expedition of 1910–1913). Ernest Shackleton 's southern party (Shackleton, Adams, Marshal, Wild) of the 1908 Nimrod expedition were

1722-669: Was going through the pack ice of the Pacific near Antarctica in an attempt to determine the position of the South Magnetic Pole. Four days later, they found their way into open water and were hoping that they would have a clear passage to their destination. But on 11 January, the men were faced with an enormous mass of ice. Sir James Clark Ross , the expedition's commander, remarked: "It was an obstruction of such character as to leave no doubt upon my mind as to our future proceedings, for we might with equal chance of success try to sail through

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1764-401: Was installed to record temperatures on the shelf and throughout the more remote parts of the continent. University of Colorado's National Snow and Ice Data Center has been studying ice shelves and, in 2002, announced that, based on several breakups of ice shelves, including Larsen B, has begun to reassess their stability. Their scientists stated that the temperature of the warmest portion of

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